In recent years, as the production of electric vehicles climbs, the consumption of lithium-ion batteries has increased dramatically, and a large number of end-of-life batteries have brought about various environmental and resource problems. Therefore, the treatment and recycling of spent lithium-ion batteries have become an urgent problem. Lithium iron phosphate (LFP) batteries have become one of the mainstream lithium batteries used in electric vehicles due to their high stability and high cycle life. However, the existing LFP recycling methods are complicated and polluting, and the recycled products are mostly alloys or metal salts, which can only be used as battery precursors. In contrast, the direct repair and regeneration of spent LFP cathode materials have many advantages, such as short process, simple method, low energy consumption, low emission, etc., which is in line with the current dual-carbon goal of China. This paper summarized the latest research progress of direct repair and regeneration of spent LFP cathode materials, including the research status of direct repair and regeneration methods such as solid-phase sintering, hydrothermal method and electrochemical method, and analyzed and compared the advantages and shortcomings of various methods. Finally, the application challenges and development prospects of direct repair and regeneration of spent LFPs were analyzed from multiple perspectives to provide references and suggestions for the research on efficient recycling of spent LFPs.

Driven by the dual carbon goals, photovoltaic power generation in China has experienced a rapid growth. As a result, the life cycle assessment of photovoltaic product on the resource and environmental impact is becoming an urgent work. Moreover, due to the decommission of early photovoltaic products, its treatment and disposal has become a crucial challenge for the green and sustainable development of China's PV sector. Therefore, this review comprehensively discusses and analyzed the resource and energy consumption, the pollutant emission and the environmental implication during the production of solar panels and the recycling of photovoltaic waste. Under the context of current policies and regulations, this review offers several suggestions to the low-carbon and green development for China's PV sector in the near future.

Natural gas is abundant, and methane is the main ingredient, which is usually used through reforming to produce high-quality clean energy. However, the catalyst deactivation caused by carbon deposition and sintering in the reforming process is a key factor hindering the large-scale industrial development of this process. Based on iron-based catalysts, the research progress on the performance of methane cracking reforming catalysts was reviewed from the perspectives of catalyst active components, supports, additives and preparation methods. Based on Ni-Fe bimetallic catalysts, the research progress on the performance of methane steam reforming and carbon dioxide reforming catalysts was reviewed. The causes of catalyst deactivation and the methods to improve the performance of reforming catalysts are described. In order to promote the industrial application of the reforming process, the carbon deposition mechanism of iron-based catalysts should be deeply explored in the future, and appropriate carriers and additives should be selected to optimize the performance of iron-based catalysts.

The choice of coolant plays a key role in the performance of liquid cooling systems for high power heat dissipation. At present, glycol and propylene glycol coolants are the most widely used. The specific heat capacity of diol coolant with different freezing points was measured by differential scanning calorimeter. By means of Fourier transform, the heat flow signal is decomposed into heat capacity components and kinetic components by modulated differential scanning calorimetry (MDSC), and the reversible specific heat value is obtained. The relevant test results provide an important reference for the research of diol coolant.

Vapor chamber is one of the devices to satisfy the thermal management of electronics. With the development of compact electronic components, the size of the vapor chamber is limited. To investigate the heat transfer characteristics of gas-liquid two-phase in a confined vapor chamber, the visualization experimental system consisting of an evaporator plate, a condenser plate, and a square quartz glass was developed in this paper. In this paper, the effects of space height and heating power on the heat transfer characteristics of vapor chambers were investigated. The interaction regimes of boiling and condensation in chambers with different heights were revealed. The experimental results show that the bubble behavior in the vapor chamber with 50 mm height is similar to that of pool boiling, whereas there is a large difference in the vapor chamber with 10 mm height. Under the lower heating power condition, the bubble in the vapor chamber with 10 mm height grows, and contacts the condensation wall and then rebounds back. While under the higher heating power condition, it is found that a bubble film on the condensation wall is generated. Under the heating power of 65 W, the thermal resistance of the vapor chamber with 50 mm height is 3.74 times of that of the vapor chamber with 10 mm height. This result shows that the heat transfer performance of the vapor chamber with lower height is deteriorated. It is hoped that the structure of the confined vapor chamber needs to be further designed and optimized to achieve the higher demand for electronic thermal management applications.

The process and mechanism of emulsion flooding is the basis for the development of emulsion flooding technology. A microfluidic visualization system was established to explore the two-phase flow characteristics of emulsion flooding and its influencing factors in porous media. The results show that the displacement mode of water and surfactant is viscous fingering, and the emulsion flooding is accompanied by droplets plugging, which can effectively inhibit viscous fingering, enhance interfacial stability and improve the displacement efficiency. The influences of capillary number, viscosity ratio and droplet to pore size ratio on the emulsion flooding were explored, and by establishing the distribution phase diagram of emulsion displacement mode with different viscosity ratio and capillary number, the transformation boundaries of stable displacement and viscous fingering of nanoparticle surfactants displacement in porous media is obtained. It is proved that emulsion can substantially increase the critical capillary number and viscosity ratio required for viscous fingering to occur, and effectively improve the spread efficiency and displacement efficiency, which provides a theoretical basis for the use of emulsion in actual crude oil extraction.

The separation of microparticles widely exists in the energy, chemical, and biomedical fields. Based on the laminar effect, a new microfluidic method was proposed and investigated with the experiment by considering different flow conditions, properties of fluids and particles. The result shows that the present method enables the efficient separation of microparticles with different sizes. The flow rate ratio and the size difference between particles significantly influence the separation performance. The separation efficiency and the purity increase with the increase of the flow rate ratio and the size difference between particles. However, the total flow rate and the property of the fluid have almost no effect on the particle separation. With the advantages of simple structure, easy operation, high efficiency and wide applicability, the present method would have great potentials in practical applications.

Based on the open-source numerical simulation software OpenGeoSys, a 3D numerical model is established, which fully considered the size characteristics of deep U-type borehole heat exchanger (DUBHE) and the distribution of complex geological parameters. The effect of factors affecting the hourly circulating temperature of the DUBHE and the long-term heat extraction performance are analyzed in this study. The thermal performance test results show that the outlet temperature of the DUBHE drops rapidly in the initial stage of operation, and gradually stabilizes in the later stage of operation. The sensitivity analysis shows that the geothermal gradient, drilling depth of the descending and ascending wells, and the length of the horizontal well have significant effects on the performance of DUBHE. The relevant conclusion will be conducive to guiding the project design and application.

In order to achieve efficient and low-cost desalination of saline wastewater using solar energy, this study designed and constructed a single droplet experimental system with thermal radiation heating. NaCl water solution was used as the working fluid and experimental research on the evaporation process of single droplets under thermal radiation heating was conducted. A laser with wavelengths of 1450 and 1930 nm was used as the thermal radiation source, with a power density between 1.4×10⁵ and 2.1×10⁵ W·m^-2, the initial mass fraction of the droplets ranged from 0.13 to 0.26 and the initial volume ranged from 1.0 to 5.0 µl. The results indicate: (1) The evaporation process of NaCl water solution droplets can be divided into four stages: heating, crystallization, thermal expansion, and cooling stage, with crystallization and thermal expansion being the main stages of droplet evaporation. (2) Increasing external radiation power or using high absorption coefficient bands can simultaneously shorten the duration of the heating, crystallization, and thermal expansion stages; increase the average surface evaporation rate. (3) Increasing the initial mass fraction or initial volume of the droplets can simultaneously increase the crystallization temperature, the maximum temperature during the thermal expansion stage and the average surface evaporation rate; the duration of the crystallization stage decreases with an increase in the initial mass fraction, but it is independent of the initial volume of the droplets. (4) Within the scope of this study, the average surface evaporation rate of NaCl water solution droplets ranged from 0.7×10^-8 to 7.4×10^-8 kg∙s^-1 and the droplet temperature remains the main factor affecting the surface evaporation rate. Based on the experimental results, an experimental correlation formula for the average surface evaporation rate of NaCl water solution droplets under thermal radiation heating was provided, with the main error between calculated and experimental values within ±20%. The results of this study can provide reference for the design and operation of desalination systems for saline wastewater under thermal radiation drive.

The flow boiling heat transfer characteristics of the refrigerant in one smooth tube (ST tube) and three enhanced tubes were compared experimentally. The three enhanced tubes used in the experiment are respectively the heat transfer tube with hydrophobic surface (HYD tube), the heat transfer tube with herringbone microfin (HB tube) and the heat transfer tube with the composite structure of herringbone microfin and hydrophobic surface (HB/HYD tube). The experiments were carried out at saturation temperatures of 279, 283 and 288 K, mass flux ranging from 50 kg/(m²·s) to 150 kg/(m²·s), and inlet and outlet vapor quality maintained at 0.2 and 0.8, respectively. It can be seen from the analysis of the results that the average heat transfer coefficient of HB tube and HYD tube is about 1.37 and 1.42 times that of smooth tube, respectively, the HB/HYD tubes with composite surface structure have the highest heat transfer coefficient, about 1.45—1.63 times that of smooth tube. According to the measured heat transfer coefficient, six empirical prediction correlation models are selected and verified by smooth tube, which proves the reliability of the selected correlation models. Combined with the structural characteristics of the enhanced tubes, a new correlation model is developed, which can predict the heat transfer coefficient of the studied enhanced tubes well. About 90% of the data points of the three enhanced tubes are within the error range of ±10%, this optimizes the scheme of industrial design of heat exchanger, thereby improving the efficiency and reliability of heat exchanger.

Printed circuit heat exchanger (PCHE), as a new type of efficient and compact micro-channel heat exchanger, has been widely used in supercritical carbon dioxide (SCO₂) Brayton cycle. The thermal and hydraulic performance of SCO₂ in airfoil PCHE channel was analyzed by numerical simulation. With the improvement of fin size, the surface heat transfer coefficient and comprehensive performance are improved, and with the increase of variation degree, the surface heat transfer coefficient and comprehensive performance are further improved. When the Angle of attack is changed to change the fin orientation, the surface heat transfer coefficient and comprehensive performance are higher than that when the angle of attack is 0°, and the surface heat transfer coefficient and comprehensive performance are further improved with the increase of change degree. Slotting in the center of the fin to change the shape of the fin, slotted fin arrangement can reduce the friction factor, improve the flow performance, but the comprehensive performance is reduced. The orthogonal test with the three structural parameters of fin size, orientation and shape shows that the dimensionless slot width of fin has the greatest influence on the flow heat transfer performance. In the sample range, the structure with fin expansion ratio of 1.4, angle of attack of 20° and no slot has the best comprehensive performance. The analysis of flow and heat transfer performance of PCHE with different airfoil structures can provide reference for SCO₂ cooling theory research and PCHE typical engineering application.

Deep-water oil and gas transmission tube is an important facility in deep-water oil and gas field development projects. Accurate simulation of the dynamic process of gas permeation and condensation is one of the key technologies for safe and reliable tube design. Taking the deep-water tube of an offshore oil field in China as the research object, the permeability law of complex gases CH₄, CO₂, H₂S and gas phase water inside the deep-water oil and gas conveying tube was studied. Considering the different factors affecting the permeability of the flexible pipe, such as polymer sealing material, thickness, gas pressure, gas temperature, flow rate, tube interface structure, etc., the hose geometry model was divided into three spaces: tube fluid, pipe structure and annulus, and the multi-phase flow heat and mass transfer coupling calculation model of composite flexible tube was established. Laboratory scale material and sample tube experiments, prototype pipeline tests and platform field tests were carried out, in which the maximum error between model results and sample tube experiments was 7%, and the maximum error between prototype pipeline tests was 12.3%. The calculation model was consistent with the trend law of field operation results, providing technical support for the design of deep-water pipeline and the safe operation management of tubes.

Pulsating heat pipe (PHP) can effectively solve the thermal management problem of high heat flux electronic components. However, its application is severely limited by its poor adaptability to heat sources with high heat flux in small areas, poor gravity resistance and large contact thermal resistance. In this paper, a butterfly PHP is designed, which has a more compact evaporation section and is suitable for high heat flux in a small area. Taking LED cooling as the application background, the thermal performance of butterfly PHP under different working conditions (heating power, different working fluid, installation angle, liquid filling rate) was studied, and the performance of LED chip thermal management system based on butterfly PHP was analyzed. The results show that under the condition of natural convection condensation, butterfly PHP shows excellent heat transfer performance and temperature equalization, and can meet the thermal management requirements of Bridgelux 100 W LED chip at any installation angle, with the highest thermal resistance not exceeding 0.292 K/W, which has great application potential. Heating power significantly affects the thermal performance of PHP. Increasing the power can restrain the amplitude of wall temperature pulsation and improve the periodicity of wall temperature pulsation. There is a critical power, and the performance of butterfly PHP is better when the heating power is greater than this power and deionized water is charged. Heating power and installation angle both affect the optimal filling rate, and they have certain interaction.

The Level-set two-phase flow coupled component mass transfer equations were used to simulate the CO₂ absorption by alkali liquor in three-dimensional T-junction cylindrical microchannels. The bubble formation and flow process, the characteristics of interphase transfer and absorption were analyzed, and the effects of inlet gas velocity, liquid velocity and alkali concentration on the CO₂ chemical absorption and mass transfer were mainly discussed. The results show that, for gas velocity of 0.08 m/s and the liquid velocity of 0.03 m/s, the formation time of a single bubble is about 0.012 s, and the bubble moving speed is almost equal to the inlet gas velocity, showing the alternating Taylor flow characteristics of bubbles and liquid plugs. The CO₂ absorption rate reaches its maximum at the initial stage of bubble formation, and gradually decreases along the outlet direction along with the decrease of mass transfer force at gas-liquid interface. When the gas velocity increased from 0.05 m/s to 0.1 m/s, the CO₂ absorptivity decreased from 62.6% to 34.8%. Conversely, when the liquid velocity increased from 0.01 m/s to 0.05 m/s, the CO₂ absorptivity increased from 18.5% to 48.4%. Furthermore, increasing the absorbent concentration from 50 mol/m³ to 250 mol/m³ raises the absorptivity from 50.8% to 79.3%.

The aim of this study is to investigate the effects of modified magnetic nanoparticle mass fraction, solution acidity and alkalinity (pH), oil-water ratio, NaCl concentration, stirring speed and emulsification temperature on the rheological properties of thick oil O/W emulsions, and to reveal the mechanism of their effects in combination with zeta potential, interfacial tension and oil droplet distribution. In order to more deeply and precisely analyze the influence of the above factors on the flow characteristics of emulsion, a six-factor and three-level positive alternating current experiment was carried out, and the power law fluid pressure drop formula was used to calculate the pressure drop per unit pipe length under each group of conditions, and the analysis of variance (ANOVA) and nonlinear regression (NLR) analysis was carried out by applying the SPSS software, and a prediction model of the pressure drop in tubing transport was constructed for the O/W-type emulsions. Finally, the optimal solution for pressure drop was solved using Matlab software. The results show that the oil-water ratio has the most significant effect on the rheological properties of emulsions, and the modified magnetic nanoparticles can successfully prepare thick oil O/W emulsions with an oil-water ratio of 8∶2. When the mass fraction of modified magnetic nanoparticles was controlled at 0.07%, the oil content was maintained at 50.38%, the NaCl concentration was 0.12 mol/L, the stirring speed was set at 664.10 r/min, and the emulsification temperature was maintained at 16.92℃, the tubing pressure drop per unit length of this thick-oil O/W-type emulsion could reach the minimum value, i.e., 66.93 Pa/m, which is an optimal solution. This optimal solution indicates that the lower mass fraction of modified magnetic nanoparticles can realize the thick oil substantial drag reduction transport under low temperature conditions. In addition, the model constructed in this paper shows a good ability to predict the pressure drop under strict orthogonal experimental conditions, which provides a reliable method to evaluate and optimize the conveying performance of thick oil O/W emulsions.

The problem of coke particle size segregation in the coke dry quenching (CDQ) furnace can seriously affect the gas-solid heat transfer efficiency. Based on the discrete element method (DEM), this study investigates the actual material surface shape, particle size distribution, and particle size segregation phenomenon generated during the coke loading process of a steel plant's coke dry quenching furnace. Reasonable optimization is carried out on the material surface of the coke dry quenching furnace to improve the particle size distribution of the stacked material surface. The results show that compared to the inclination angle of the bell and the angle between the dividing plate, the direction of the beam has a greater impact on the shape and particle size uniformity of the material surface. Due to the diversion effect of the bell beam on coke particles, it is easy to form inclined stacking material surfaces, resulting in uneven distribution of coke particles. After the direction of the rotating beam is parallel to the opening of the coke pot, the inclining effect of the material surface is weakened, and the segregation of coke particle size is reduced. Under the optimized conditions of 40°—60° inclination angle of the material bell, 30°—60° angle of the dividing plate, and beam direction, the maximum reduction in material height difference is 70.8%, and the maximum reduction in standard deviation is 49.4%, especially at larger angles, the effect is significant, which helps the gas flow uniformly in the packed bed.

Water management is an important method to improve the performance of proton exchange membrane fuel cells (PEMFCs). In order to solve the problem of cathode channel“flooding”in fuel cells, it is necessary to clarify the motion laws of droplets in different channel structures to find ways to accelerate droplet discharge. In this paper, two-phase numerical simulation is used to simulate and analyze the motion behaviors of droplets with different sizes, initial positions and quantities in two types of serpentine flow channel structures, focusing on the main factors affecting the droplet discharge time and droplet motion behaviors. The results show that the droplet size and the contact mode with the curved part greatly affect the droplet motion attitude and discharge time, the larger the droplet diameter, the shorter the discharge time, and the increase of the diameter effectively accelerates the inner droplet discharge. At the same time, compared with the rounded bend structure of the runner, the semicircular bend structure of the runner is more conducive to the discharge of the droplets.

Supercriticl CO₂ has shown great potential in the fields of tower solar thermal power generation and nuclear energy industry. In order to study the heat transfer characteristics of supercritical CO₂ in an inclined upward tube under cooling conditions, numerical simulation methods were used to simulate it by dividing it into liquid like zone, quasi critical zone, and gas like zone according to temperature, analyze the density and temperature field distribution of supercritical CO₂ in an inclined upward tube, as well as the variation of its convective heat transfer coefficient and average resistance coefficient along the tube length, and study the effects of different tilt angles, mass fluxes, and pressures on the heat transfer performance of supercritical CO₂. The research results indicate that the change in tilt angle has an impact on the convective heat transfer coefficient and average resistance coefficient of supercritical CO₂ in the liquid like region, but has no effect on the gas like region. An increase in mass flux can increase the convective heat transfer coefficient and reduce the average drag coefficient. The change in pressure has a significant impact on the convective heat transfer characteristics in the quasi critical and gas like zone.

Adequate mixing of the curing agent and binder in hydroterminated polybutadiene (HTPB) propellants is critical to propellant performance, and the kenics static mixing tube enables adequate mixing of high-viscosity fluids. The viscous shear curve of the propellant slurry was measured using a Minilab miniature twin-screw rheometer. Numerical simulations of the kenics static mixing tube for HTPB propellant slurries has been carried out by computational fluid dynamics (CFD) to analyze the relationship between the inlet flow rate, the number of elements and the element length-to-diameter ratio of the kenics static mixing tube and the pressure drop and mixing effect. Numerical simulations show that the pressure drop is proportional to the inlet flow rate and linearly related to the number of elements, and more than 45% of the pressure loss is concentrated at the nozzle of the mixing tube for extrusion moulding. 8 mixing units can complete 99.9% of the mixing, and 12 mixing units can complete 99.99% of the mixing. The secondary flow in the radial direction increases as the L/D ratio decreases. An increase in the L/D ratio from 0.5 to 1.25 enhances mixing and reduces energy consumption at the same time.

Direct air capture (DAC) is a highlight among carbon capture and storage technologies in recent years, and adsorption is the mainstream DAC technology. The performance of adsorbent is the key of adsorption DAC. The ideal adsorbent should satisfy the following advantages: high CO₂ capacity, low regeneration energy consumption, and high stability. Generally, the capacity of amine-impregnated adsorbent is higher, but the support materials decide the adsorbent performance. In this study, γ-Al₂O₃ and MCF was impregnated with PEI to discuss the effects of support materials on adsorbents. According to the results, the effects of support materials on the adsorbents are mainly reflected in CO₂ capacity and adsorption kinetics. In 0.4 mbar and 25℃, the capacity of PEI-MCF and PEI-Al₂O₃ are 1.76 mmol/g and 1.49 mmol/g respectively. As for adsorption kinetics, PEI-MCF is 62% faster than PEI-Al₂O₃ in the dry condition. In the humid condition, the capacity and kinetics of PEI-MCF is also better than PEI-Al₂O₃. However, the cycle stability of two materials has little difference, which indicates scarce influence of support materials.

Based on the Euler-Euler multiphase flow model, the oil-water separation multiphase flow process in a micro-bubble swirling air flotation device was numerically calculated. In the actual production process, the oil droplet in the device will collide with the injected swirling gas and adhere to form an oil drop-bubble adhesive. Therefore, the three-phase flow process of oil-gas-water in the micro-bubble swirling gas flotation device was simplified into a two-phase flow process of oil-gas mixed phase and water phase. The mixed phase density of oil and gas was determined by comparing the actual separation efficiency with the calculated results. Then, through the analysis of the calculation results, the influence law of the width and inclination angle of the diversion tube on the swirl strength and separation efficiency of the micro-bubble swirl air flotation device was obtained. The numerical calculations results show that the separation efficiency and the oil content of the outlet of the device increase first and then decrease with the increase of the width of the diversion pipe, and the separation efficiency of the device reached the best when the diversion pipe width was around 53 mm. The separation efficiency of the device and the oil concentration at the top outlet first increase and then decrease with the increase of the diversion tube inclination angle. The separation efficiency of the device reaches the optimum when the diversion pipes inclination angle was around 9°.

Platinum group metal (PGM) elements of Pt (platinum), Pd (palladium) is a kind of rare metal elements with high economic value, widely used in industrial, scientific, medical and high-tech fields. Because the mineral supply of PGM cannot meet the growing market demand. The recycling of secondary resources such as waste automobile catalysts and electronic waste has become an important way to alleviate the contradiction between supply and demand of PGM. In this paper, a deep eutectic solvent polymer inclusion membrane electrodialysis integrated system for one-step separation and recovery of Pt(Ⅳ) and Pd(Ⅱ) was constructed by simulating the actual leaching solution of spent automobile catalysts. The effects of various process parameters in the system on the separation of platinum group metals in the leaching solution of spent automobile catalysts were systematically investigated. The results showed that the TOPO/thymol with a molar ratio of 1∶1 had the best transport performance for Pt and Pd. The extraction efficiency of Pt and Pd were 99.90%, and the stripping efficiency were 65.96% and 77.93%, respectively. The 0.05 mol·L^-1 KSCN as the stripping solution had a good separation effect on Pt and Pd, and the stripping efficiency of Pt and Pd were 62.54% and 89.19%, respectively. This study is of great significance for the efficient separation and recovery of Pt(Ⅳ) and Pd(Ⅱ) in spent automobile catalysts.

Soy sauce usually contains a high concentration of NaCl due to the fermentation process as well as shelf-life requirements, while excessive NaCl intake as well as low potassium intake by the human body can cause physical diseases. Therefore, in this study, electrodialysis was used to replace Na⁺ with K⁺ to achieve the preparation of low-sodium and high-potassium healthy soy sauce. Firstly, experiments were carried out using commercial membranes and it was found that the Na⁺ removal rate was 37.3% and the K⁺ increase factor was 2.83 times. It could not reach the best standard of low-sodium and high-potassium healthy soy sauce (Na⁺ content reduced by half and K⁺ content increased by five times). Therefore, the polyionic liquid membrane was prepared and applied to the electrodialysis experiment, and the Na⁺ concentration in soy sauce was reduced from the initial 2.6 mol/L to 1.39 mol/L, and the K⁺ concentration was increased from the initial 0.18 mol/L to 0.93 mol/L, which was very close to the best standard of low-sodium and high-potassium healthy soy sauce.

Glutathione (GSH) is the most abundant non-protein thiol within cells. It has strong electron donating ability and participates in redox reactions in organisms, which endows it with multiple physiological functions and it is widely used in food, pharmaceutical and cosmetics industries. Glutathione bifunctional synthase is the key enzyme for catalyzing the production of GSH and improvement of its catalytic efficiency is of significance to GSH biosynthesis. In this study, the glutathione bifunctional synthasefrom Streptococcus thermophilus (St-GshF) was chosen for study object. A high-throughput screening method based on the fluorescence colorimetric effect generated by the reaction between GSH and ortho benzaldehyde was established. Using semi-rational design, St-GshF was engineered and the mutant St-GshF (S27Q/G510P) was obtained. Its activity was 1.75 times higher than the wild type. The polyphosphate kinase was coupled to construct the efficient glutathione biosynthesis system and after optimization of the reaction conditions, 17.36 g/L glutathione was obtained with a yield of 94.22%, laying an important foundation for the large-scale production of glutathione.

Diffusion layer (DL) is an essential structure of a direct methanol fuel cell (DMFC) membrane electrode assembly (MEA), which provides a channel for the mass transfer of reactants from the flow field to the catalytic layer. As the reaction proceeds, the DL also provides a channel for the transport of electrons from the catalytic layer to the flow field. Therefore, the conductivity and surface morphology of the DL affects the overall performance of the fuel cell. The cathode diffusion layer (CDL) based on the foam carbon (FC) material could reduce the contact, charge transfer, and mass transfer resistance between the fuel cell membrane electrode and the current collector plate thanks to the FC's electrical conductivity and three-dimensional network structure. Moreover, the high porosity and small surface contact angle (CA) of FC could also increase the proportion of DMFC cathode catalytic layer exposed to the air and provide extra gas-liquid two-phase channels, which is the better catalyst support. Experimental results show that compared with the DMFC based on traditional carbon paper (CP-DMFC), the maximum power density of the DMFC with FC as the CDL (FC-DMFC) increases from 24.47 mW/cm² to 39.24 mW/cm², the contact resistance decreases from 0.588 Ω to 0.494 Ω, the charge transfer resistance decreases from 2.784 Ω to 1.816 Ω, and the mass transfer impedance decreased from 1.689 Ω to 1.417 Ω. Under a discharging current of 100 mA/cm², the discharge time of FC-DMFC is 60 min, while the discharge time of CP-DMFC is 46 min, and FC as a diffusion layer has a longer discharge time. It shows that the new structure has higher energy efficiency under the same methanol concentration and volume than the conventional structure.

The mixed fluid cascade (MFC) process is one of the most competitive processes for large-scale base-loaded natural gas liquefaction process, which consists of three mixed refrigeration cycles of natural gas pre-cooling, liquefaction, and subcooling, which involves key parameters such as refrigerant ratios, refrigeration temperatures, and pressures, which makes the process complex and sensitive. For the MFC liquefaction process, an optimization function with specific power consumption as the objective is established, and with the help of Aspen HYSYS process simulation and physical property calculation, the sequential quadratic programming (SQP) optimization algorithm is used to globally optimize the MFC process and conduct energy efficient analysis of the process. The optimization results show that after the global optimization, the specific power consumption of the MFC liquefaction process is 899.36 kJ/kg, which is 7.38% lower. The cold-heat composite curve of the multi-strand flow heat exchanger is better matched. Through the effective energy analysis, it is found that the effective energy loss of the refrigeration compressor unit accounts for the largest proportion, and the effective energy loss of the multi-strand flow heat exchanger is significantly reduced after the optimization, and the effective energy efficiency of the liquefaction process is increased from 38.17% to 41.21%, and the energy utilization efficiency is improved obviously.

A fixed-bed reactor was used to study the simultaneous desulfurization and denitrification of red mud at 110℃, as well as the effects of water vapor concentration and SO₂ to NO ratio. The physical properties and chemical composition of red mud were measured by BET (Brunauer Emmet Teller) surface area and porosity analyzer, pH meter, laser particle size analyzer (LDSA) and ICP (inductivity coupled plasma mass spectrometry). The experimental results showed that the denitrification efficiency of red mud was 2.4 times that of Ca(OH)₂. The effect of NO content in the reaction gas on the removal of SO₂ was less than 15%. When the SO₂ to NO ratio approached 5, the removal efficiency of NO nearly approached 100%. The optimal range for the effect of water vapor was around 10%. When the water vapor concentration was too high, the conversion and removal of NO can be affected in the early stage, while the desulfurization and denitrification in the later stage were promoted. The effective components for desulfurization and denitrification in red mud mainly included alkaline components and metal oxides.

The deep treatment of various organic pollutants contained in coal chemical wastewater and the improvement of its reuse rate have important ecological and economic significance. However, some pollutants have high concentrations and traditional wastewater biological treatment processes cannot completely remove them. Failing to meet increasingly stringent wastewater discharge standards. This article constructs a structure-activity regulation mathematical model for the advanced oxidation reaction system of coal chemical wastewater based on a microinterface enhanced reactor, clarifying the strengthening mechanism and efficiency of microinterface enhanced technology on ozone advanced oxidation. The results showed that under the same conditions, the bubble size decreased from 10.0 mm to 0.1 mm, and the COD removal rate of wastewater increased from 70.02% to 90.02%. At the same gas volume, when the COD removal rate reaches 70%, the microinterface reactor can increase the wastewater treatment capacity by 66.50% compared to the ordinary bubble reactor. Provide strong reference for the scaling up and design of advanced oxidation treatment of coal chemical wastewater at microinterfaces.

Aiming at the problem of low manganese leaching and recovery in the current electrolytic manganese metal liquid-making process, this paper takes the liquid-making process as the research object, carries out the simulation experiments of the existing industrial production liquid-making process (T₁), anode liquid leaching (T₂), anode liquid leaching-washing (T₃) liquid-making process, and researches the influence of different liquid-making processes on the leaching and recovery of manganese in manganese ores, as well as on the migration of calcium, magnesium and iron. The results showed that the manganese leaching rate was T₃ (92.76%±0.40%)≈T₂ (92.14%±0.62%) > T1 were carried out to study the effects of different liquid preparation processes on the leaching rate and recovery rate of manganese and the migration of calcium, magnesium and iron in manganese (89.59%±2.43%), and the manganese recovery rate was T₃ (91.18%±0.47%) > T₂ (87.02%±0.74%) > T₁ (73.97%±2.37%), indicating that the leaching rate and recovery rate of manganese in manganese ore can be effectively improved by anodic leaching, and the recovery rate of manganese leaching can be effectively improved by washing process. On the basis of the existing liquid production process, the anodic leaching process will not increase the migration proportion of calcium and magnesium in manganese ore to the liquid phase, but will increase the migration proportion of iron, and the addition of the washing process will not increase the migration proportion of calcium and iron in manganese ore to the liquid phase, but will increase the migration proportion of magnesium.

Utilizing conductive carbon black as the substrate and SiH₄ as the silicon source precursor, silicon-carbon composite anode material were prepared for lithium-ion batteries via a fixed bed CVD reactor. Two schemes were studied: sole deposition of SiH₄ and its co-deposition with C₂H₄. Additionally, the impact of carbon encapsulation using C₂H₄ as the carbon source on the lithium storage performance was investigated. The experimental results reveal that sole SiH₄ deposition yields smaller Si nanoparticles, with a reduction in Si loading as the deposition temperature increases.During the co-deposition of SiH₄ and C₂H₄, C@SiC composite structure is formed, and the crystallinity and grain size of elemental silicon decrease with the increase of C₂H₄ proportion. Under the co-deposition of SiH₄/C₂H₄ and C₂H₄ carbon coating conditions, a composite structure featuring coexistent Si, SiC, and C crystals is observed, enhancing sample material cycling performance albeit with a notable decrease in capacity.

Aiming at the problem of low thermal conductivity of solid-liquid phase change composites due to the uneven distribution of carbon materials, the dispersion of CNT in the system was optimized by in situ polymerization and combined with functionalized surface modification, and the thermally enhanced composite phase change material of polymers of methyl methacrylate (PMMA) / polyethylene glycol (PEG600) / carbon nanotubes (CNT) was proposed. First, the optimal mass ratio of PMMA as the base for encapsulating the phase change material PEG600 was determined to be 3∶7, when the material combines good encapsulation and thermal storage properties. Secondly, using the in situ polymerization method, which is good for regulating the viscosity of the system, CNT was introduced into the PMMA/PEG600 system to the maximum extent up to the concentration threshold, which greatly enhanced the thermal conductivity of the composite material. When the mass fraction of CNT was 7%, the thermal conductivity of the composite was 0.438 W/(m·K), which was about three times of that without CNT. Finally, hydroxyl-functionalized surface modification for CNT further enhanced the thermal conductivity. When the mass fraction of hydroxylated CNT was 3%, the thermal conductivities of ternary composites containing CNT and hydroxylated CNT were enhanced by 8% and 92%, respectively, compared with those of binary composites.

The inclusion complexes of VAA with β-cyclodextrin (β-CD) and its derivatives hydroxypropyl β- cyclodextrin (HP-β-CD) and sulfobutyl ether β-cyclodextrin (SBE-β-CD) were prepared by freeze-drying method, and the inclusion complexes were characterized by Fourier infrared spectroscopy (FT-IR), nuclear magnetic resonance hydrogen spectroscopy (¹H NMR), and scanning electron microscope (SEM), and phase solubility, thermal stability, solubility and molecular binding mode were analyzed. The results of the phase solubility experiments showed that all the three cyclodextrins formed an inclusion ratio of 1∶1 with VAA, among which HP-β-CD had the highest stability constant and was more effective than the other two cyclodextrins in the inclusion of VAA. The experimental results of thermal stability and solubility change tests showed that the thermal stability and water solubility of the three inclusion compounds were substantially improved compared with free VAA, with VAA/HP-β-CD being the best, with the heat loss rate decreasing from 52.6% to 5.2%; and the water solubility increasing from 1.9×10^-4 to 100 g/100 g. The results of the molecular docking showed that HP-β-CD enlarged the β-CD cavity length so that VAA was completely encapsulated and formed intermolecular hydrogen bonding with VAA, and the inclusion complex formed with VAA had minimal binding energy. The above results indicate that HP-β-CD is an excellent encapsulation carrier for VAA and can effectively improve the application performance of VAA.

With the continuous development of energy storage technology, lithium-ion batteries are widely applied in electric vehicles, energy storage systems and other fields due to their high energy density. However, the performance of lithium-ion batteries is significantly affected by temperature, either too high or too low temperature will affect its performance and the suitable operating temperature of the batteries is 25—45℃, so battery thermal management is indispensable. The thermal management technology based on phase change material has the advantages of good temperature uniformity and no need for additional energy input, thus has attracted widespread attention from researchers. The influence of the geometry of the composite phase change material (CPCM) structure was investigated using finite element method on the thermal management performance for the typical prismatic battery in this work. The simulation results showed that CPCM with better thermal conductivity had a stronger heat dissipation effect when used in battery thermal management. When the amount of phase change material was the same, the temperature distribution of the cylindrical structure was more uniform and had better thermal management performance.

The detonation instability of two multi-component components with different C/H ratios is analyzed. Detonation experiments were carried out in a D=80 mm tube to analyze the characteristics of detonation velocity and cell structure changes of the multi-component components. The influence of hydrogen partial pressure on the instability of multi-component detonation was analyzed from the angle of three-wave point trajectory spacing, pitch and chemical reaction process. It is found that the detonation velocity of multi-component #1 is similar to that of hydrogen premixed gas, although it fluctuates, it is generally stable, and is always stable above 0.95V_CJ. The detonation velocity of multi-component #2 is similar to that of methane premixed gas, and the fluctuation range is larger. From the perspective of cell structure characteristics, it is found that the variation trend of the number of detonation helical heads is similar to that of the velocity. The stability of component #1 is greater than that of component #2. The results are helpful to grasp the detonation propagation mechanism of multi-component.