Alloy impellers are widely used in compressors and turbines in the fields of energy and power engineering and chemical industry. Their performance and life directly affect the efficient operation and reliability of mechanical systems. However，in the complicated operation conditions，solid particles and/or droplets carried by high-velocity fluids continuously impact the impellers，resulting in erosion and wear. Over time，this causes material spalling，microcrack propagation，and geometric deformation. As the damage accumulates，it ultimately leads to degradation of aerodynamic capability and even sudden failure. In this paper，the research progress on erosion and wear of alloy impellers was systematically reviewed. Furthermore，it analyzed the mechanism and influencing factors of wear types，anti-erosion materials，and erosion and wear protection measures. In this way，the study aimed to provide a theoretical basis and technical reference for improving the corrosion resistance of impellers. The types and mechanisms of erosion wear could be divided into four categories： gas-solid erosion wear，liquid-solid erosion wear，droplet erosion wear，and cavitation wear. Gas-solid erosion and liquid-solid erosion were commonly found in industrial fluids containing solid particles. These phenomena eroded the surface of materials through micro-cutting，plastic deformation，and crack propagation mechanisms. Micro-cutting theory and deformation wear theory have explained the wear behavior under low-angle and high-angle impacts，respectively. Beyond these mechanisms，the secondary erosion theory had further incorporated the secondary energy distribution effect after particle breakage. The droplet erosion mainly occurred in high-speed，such as steam turbineblades，where the droplet impact caused microplastic deformation on the surface and forms cavities. Subsequently，these cavities gradually expanded into continuous grooves，and a process further aggravated by the water hammer effect and stress wave propagation. The formation and rebound of secondary water droplets further boosted the erosion. Cavitation wear results from the collapse of cavitation bubbles caused by sudden changes in fluid pressure. This process generated micro-jets and high temperature and high pressure that impacted the surface，inducing material fatigue，lattice dislocation，and punctate spalling. In particular，the wear showed a synergistic effect with droplets in centrifugal compressors. The erosion wear was influenced by a variety of factors，including impurity，material properties，and environmental parameters. For the impurity，particle shape，particle size，impact velocity，and impact angle had significant impacts on the wear process. Regarding material properties，surface hardness，toughness，yield strength，and modulus of elasticity affected erosion resistance. For example，Ti6Al4V alloy exhibited excellent resistance to droplet erosion due to its high hardness and toughness. Environmental parameters such as fluid viscosity，saturated vapor pressure，and surface roughness indirectly exacerbated cavitation damage by changing cavitation nucleus formation and collapse behavior. To extend the life of impeller，the research focused on substrate materials，surface coating，structural design，and surface strengthening. In terms of substrate selection，titanium alloys （such as Ti6Al4V）were widely used benefitting from their high strength and corrosion resistance. But the high brittleness limited the application in some scenarios. Cobalt-based alloys absorbed impact energy through the phase transformation of the face-centered cubic structure to the hexagonal densely packed structure. This principle enabled them to exhibit excellent droplet erosion resistance. For the surface coating，the WC-Co coating prepared by supersonic flame spraying （HVOF）had a good performance due to its high hardness and low porosity. However，the spraying temperature needed to be strictly controlled to avoid carbide decomposition. The microhardness of the Cr₃C₂-NiCr coating by plasma spray welding was 6.46 times that of the substrate，and the anti-abrasive wear performance was significantly improved. In comparison，the Ni60A coating prepared by arc spraying and laser cladding technique reduced the crack sensitivity and water erosion depth by 53.2%. This enhancement primarily resulted from refining the grain and introducing the TiB₂+TiC eutectic structure. The impeller structure optimization inhibited erosion through strategies such as biomimetic design，gap structure and balanced holes. Drawing on the pectoral fin shape of humpback whales，the bionic design achieved blade leading edge optimization with consequent reductions in cavitation volume and shock wave intensity. The gap structure used the conductive characteristics and pressure self-equilibrium to inhibit cavitation. The cavitation incidence was reduced by optimizing the circumferential position of the equilibrium hole. In the surface strengthening process，the high-power diode laser （HPDL）method was used to generate α martensitic phase on the surface of titanium alloys. This phase transformation enhanced droplet erosion resistance by 2 times. Gas nitriding formed a TiN/Ti₂N composite layer on the surface of Ti6Al4V，and the erosion resistance was increased by 80%-125%. Shot peening and cavitation blasting reduced erosion by up to 95% by introducing compressive residual stresses and reducing surface roughness. At present，most of the research focused on a single protection technique，while erosion and wear were often coupled by multiple mechanisms under actual working conditions. In the future，we can focus on combining a variety of optimization schemes to improve impeller erosion resistance. For instance，the gradient structure alloy impeller material design may be integrated with surface coating for synergistic effects. Additionally，the impeller structure optimization can be considered alongside surface strengthening treatment to address multiple failure modes. In this way，the impeller's erosion resistance can be comprehensively improved to meet the needs of long life and high performance of the impeller under complex working conditions.

With the development of industrialization，a large number of chemicals are used in daily activities，resulting in more and more refractory organic pollutants in environmental waters，such as pesticides widely used in agriculture，pharmaceuticals employed in the medical industry，dyes and preservatives used in everyday life，even daily necessities such as skin care products and cosmetics. These organic pollutants can enter the environmental water body through various ways and accumulate residues in it and finally enter the human body through direct ingestion，bioaccumulation，and other ways，which pose a great threat to human health. Advanced oxidation technologies （AOPs）are a typical and effective water treatment method. Most AOPs are based on peroxide compounds that can be activated，such as hydrogen peroxide （H₂O₂），peroxymonosulfate （PMS），peroxydisulfate （PDS），and peracetic acid （PAA）for Fenton/Fenton-like reactions. Advanced oxidation technology using persulfate （PS）as an oxidant （including PMS and PDS）can produce a series of reactive oxygen species （ROS）such as sulfate radical （${\text{SO}}_4^{·-}$），hydroxyl radical （·OH），superoxide radical （${\text{O}}_2^{·-}$），and singlet oxygen （¹O₂）after activation. Compared with H₂O₂，PS has a higher oxidation potential，a longer half-life，and a wider pH range，which makes PS-based wastewater purification widely concerned. However，the slow activation process and low degradation rate of PS limit its development. As the largest country in molybdenum resources，China has an abundant reserve. The d-orbital electron configuration of molybdenum is flexible，which gives Mo a variety of valence states. Molybdenum-based oxides，molybdenum-based chalcogenides，molybdenum-based carbides，and other molybdenum-based compounds have stable physicochemical properties，good electrical conductivity，flexible valence ability，and excellent photoelectron-hole generation ability via light response. These make them considered good PS activators，and can also be used as cocatalysts in composite catalysts to provide electrons for the reduction of other transition metals，and also have significant advantages in the field of light-assisted activation of PS. In this paper，the mechanism of radical production by PMS，PDS，and H₂O₂ was analyzed from the structural perspective and compared with the difficulty of their activation to wastewater degradation by structural symmetry. The PS degradation mechanism involved multiple steps，including O-O bond cleavage （activation），free radical generation，and degradation of target pollutants，among which PS activation and free radical generation were the key steps. Focusing on the free radical pathway and non-free radical pathway，the possible PS activation pathways in the degradation process of pollutants were described，and the fundamental differences between the formation modes and degradation mechanisms of both of the above were analyzed by combining valence bond theory and crystal field theory. The paper recommended the existence forms of several molybdenum-based compounds，such as MoO₂，MoO₃，MoS₂ （one trigonal-MoS₂，two hexadonal-MoS₂，three rhombohedral-MoS₂），MoSe₂，MoC，and Mo₂C，were discussed in detail，and their structural characteristics and corresponding physicochemical properties were discussed in depth. These Mo-based materials have shown significant advantages in many fields，such as transition metal activation and photoactivation. Mo-based materials could not only quickly break the persulfate O-O bond to form ${\text{SO}}_4^{·-}$ and ·OH through the oxidation process，but also reduce the oxidized Mo（Ⅵ）and produce ¹O₂ to achieve efficient degradation of organic pollutants. At the same time，Mo-based materials could also act as cocatalysts to synergize with other transition metals and participate in pollutant degradation as active and reducing components. Mo-based compounds could also play an important role in the generation of photogenerated electrons under light to assist in the activation of PS. Finally，some problems in the field of molybdenum-based catalysts were pointed out. For example，Mo-based catalysts have shown poor cycling stability in some studies，which was speculated to mean that part of the active sites were occupied by reaction intermediates，resulting in a decrease in the activation ability of PMS. Most of the Mo-based catalysts reported so far remain in the laboratory stage，and their performance in complex actual water bodies was often not ideal，which was far from the purpose of practical application. How to realize the practical application of Mo-based catalysts and then realize the industrial application should be studied.

This study delved into the comprehensive investigation of the corrosion behavior and mechanisms of high-strength marine engineering steel HY80-N. Utilizing advanced techniques such as optical microscopy （OM）and scanning electron microscopy （SEM），the microstructure of the steel was meticulously examined to identify the presence of inclusions. Subsequent to the microstructural analysis，simulated seawater immersion corrosion tests were conducted at various time intervals，providing a dynamic understanding of the corrosion progression. The corrosion behavior was extensively characterized through a series of electrochemical tests，including impedance measurements，open circuit potential analysis，and polarization curves. Corrosion rates were quantified using the weight loss analysis method，yielding valuable corrosion rate curves that offered insights into the kinetics of the corrosion process. Scanning electron microscopy was employed to provide a detailed study of the initiation of corrosion in simulated seawater. This technique revealed the electrochemical characteristics of inclusions and microstructural features，shedding light on the local corrosion phenomena. Additionally，scanning electron microscopy was utilized to observe and analyze the corrosion morphology，providing a visual representation of the structural changes occurring during the corrosion process. Results from the study unveiled that in the initial stages of corrosion，pitting predominantly occurred around Al₂O₃ inclusions. As corrosion progressed，the extent of corrosion expanded，leading to a proportional reduction in the steel's corrosion resistance. As the immersion time increases，the capacitance loop diameter of marine engineering steel significantly decreased，and the charge transfer resistance （R_ct）value decreased from 2.859 to 1.143 kΩ·cm². The double-layer constant phase element admittance parameter CPE_dl-Y₀ value changed from 7.681×10⁻⁵ to 6.334×10⁻³ sⁿ·Ω⁻¹·cm⁻¹，where s denotes seconds，and n is the dimensionless phase angle exponent of CPE. Generally，the double layer constant phase element CPE_dl value was positively correlated with the quantity and area of pitting corrosion. Therefore，with the increase in immersion time，the surface of marine engineering steel experienced a greater number of pitting corrosion events，leading to a two-order magnitude increase in CPE_dl values. Chloride ions were identified as the main corrosive species on the surface of marine engineering steel，subsequently leading to the formation of localized corrosion microcells，manifested by the decrease in （R₁+R_ct），where R₁ refers to the film resistance. When corrosion products accumulated near the pitting，it tended to weaken the corrosive impact of chloride ions，resulting in a slight increase in R₁. After 12 h of immersion，sporadic peaks in current density were observed as the applied potential exceeded the corrosion potential （E_corr），indicating the initiation of pitting corrosion and an activated state of the material surface. With prolonged immersion，the corrosion potential of marine engineering steel decreased from –451.42 to –478.73 mV，and the corrosion current decreased from 9.51 to 8.58 μA·cm^-2. After 48 h of immersion，the corrosion potential further decreased to –507.59 mV，and the corrosion current increased to 82.77 μA·cm^-2，accompanied by an increase in b_C （cathodic Tafel slope）values. Simultaneously，the passivation region decreased in the polarization curve，and the corrosion current gradually increased. The material was losing its passivation，indicating that pitting had penetrated into the crevice，leading to a significant reduction in the material's corrosion resistance. Three-dimensional morphology analysis illustrated enhanced corrosion around Al₂O₃ inclusions after 12 h of immersion. This enhancement was characterized by deepening pits and a noticeable height difference compared to the surrounding uncorroded areas. This phenomenon was attributed to the accelerated dissolution of the matrix around the Al₂O₃ inclusions. Throughout the entire corrosion process，the inclusions played a detrimental role，acting as accelerators for the corrosion of marine engineering steel. In conclusion，although the marine engineering steel exhibited a uniform grain distribution，the presence of Al₂O₃ inclusions introduced a susceptibility to corrosion in marine environments. Microscopic analysis，coupled with corrosion rate calculations from samples immersed for different durations，highlighted that pitting initiated primarily around the inclusions，expanding as the corrosion process advanced，ultimately compromising the steel's corrosion resistance. The comprehensive analysis involving electrochemical impedance spectroscopy，polarization curves，and three-dimensional morphology emphasized the intricate corrosion mechanisms. Chloride ions were identified as the primary corrosive species，with inclusions initiating pitting and forming localized corrosion cells. The findings underscored the detrimental impact of inclusions on the corrosion resistance of marine engineering steel throughout the entire corrosion process，providing valuable insights for the development of corrosion-resistant materials in marine applications.

Perovskite materials have garnered extensive attention in the application domain of optoelectronic devices due to their merits such as long carrier diffusion length，high carrier mobility，low trap state density，and high photoluminescence quantum efficiency. In 2009，Miyasaka et al. utilized MAPbI₃ as the light absorption layer in the structure of dye-sensitized solar cells （DSSC），attaining a photoelectric conversion efficiency （PCE）of 3.8%，realizing the first application of perovskite materials in solar cells. Perovskite solar cells （PSCs）have emerged as a promising technology in the field of renewable energy due to their high efficiency and low production costs. Among various materials，zinc oxide （ZnO）nano-semiconductor thin films have gained significant attention as an electron transport layer （ETL）in PSCs. ZnO offers several advantages，including its high electron mobility，low cost，and reduced energy consumption during fabrication. These properties make ZnO an ideal candidate for the production of flexible devices，positioning it as a superior alternative to traditional titanium dioxide （TiO₂）ETLs. Despite the extensive research and attention that ZnO nano-semiconductor thin films have received in the context of PSCs，there remains a need for further exploration，particularly concerning their application in all-inorganic systems. While most studies have concentrated on the use of ZnO in organic-inorganic hybrid PSCs，reports on its integration into the all-inorganic CsPbI₃ system are notably fewer. This gap in research prompted the investigation presented in this paper. To address this，the colloidal spin-coating method was employed to fabricate ZnO nanoparticle layers on fluorine-doped tin oxide （FTO）substrates. By manipulating various parameters such as precursor concentrations，annealing times，and annealing temperatures，the study aimed to understand how these conditions influence the formation and growth of ZnO nanoparticle layers，and subsequently，the performance of the all-inorganic perovskite layer and the PCE of the solar cell device. The experimental results demonstrated that the concentration of the colloidal solution，along with the duration and temperature of the annealing process，played a crucial role in determining the quality of the ZnO nanoparticle layers. These factors directly impact the formation and growth of the perovskite thin films. Specifically，when a colloidal solution with a concentration of 0.50 mol·L⁻¹ was annealed at a temperature of 300 ℃ for a duration of 5 min，the resulting ZnO films exhibited the fewest surface pores and the most uniform particle distribution. This optimal condition was found to be most favorable for the growth of all-inorganic perovskite films，thereby enhancing the photoelectric performance of the solar cell devices to a significant extent. Furthermore，a layer composed of ZnO nanoparticles，which had been subjected to various annealing temperatures，was employed as the electron transport layer in this study. Once a completely inorganic perovskite thin film was spun onto its surface，the sample was exposed to an environment with a relative humidity of 10%±5%. Under these conditions，the phase transformation process of the perovskite thin film was closely monitored. It was observed that after just one day of exposure，the perovskite thin film deposited on the ZnO surface that had been annealed at 250 ℃ started to undergo a phase transformation，resulting in the formation of a yellow phase. As the days passed，more significant changes were noted. Specifically，after 15 days，the perovskite film on the ZnO surface annealed at 350 ℃ also began to experience phase changes，and by the 30th day，nearly the entire film had transitioned into the yellow phase. In contrast，the majority of the perovskite film on the ZnO surface annealed at 300 ℃ retained its original black phase throughout the 30-day period. This remarkable stability suggested that the perovskite material produced under these specific conditions exhibited a high degree of phase stability. The primary reason behind this stability could be attributed to the fact that the perovskites created under these conditions possessed a higher level of crystallinity，fewer imperfections on their surfaces，and a slower rate of interaction with the moisture present in the surrounding air. These factors collectively contributed to the enhanced stability of the perovskite thin film，making it less susceptible to environmental influences and phase transitions over time. Under these optimized conditions，the solar cell achieved a peak PCE of 6.37%，with a short-circuit current density （J_sc）of 12.15 mA·cm⁻²，an open-circuit voltage （V_oc）of 0.79 V，and a fill factor （FF）of 66.36%. After being stored for 480 h in a nitrogen-protected environment with a relative humidity of 10% to 15%，the initial efficiency of the perovskite solar cell was retained at 79.1%. These findings were promising and suggested that further research and development in this area could lead to the creation of more efficient and cost-effective solar cells，potentially accelerating their commercialization and widespread adoption. The insights gained from this study were expected to contribute positively to the advancement of ZnO-based ETL PSC technology. By providing a pathway for the low-temperature and low-cost preparation of inorganic PSCs，this research not only enhanced our understanding of the material's potential but also paved the way for practical applications in the renewable energy sector.

Hydrogen energy，as a clean and renewable energy source，presents a promising pathway to accelerate the achievement of "Carbon neutrality" and "Carbon peak" targets. The application of hydrogen energy from generation to final use included four links，namely the preparation，storage，transportation，and application of hydrogen. Storage and transportation contributed to 30%-50% of the overall cost. Therefore，the development of safe and efficient hydrogen storage and transportation technologies was critical to unlocking the full potential of hydrogen energy applications. Among the various hydrogen storage materials，MgH₂ was one of the hydrogen storage materials with the most development potential，due to its abundant resources，low price，high hydrogen storage capacity （theoretical hydrogen storage capacity was 7.6%），and good cycling performance. However，the hydrogen release temperature was high，and the hydrogen release kinetic performance was poor，which limited its large-scale application. Catalyst doping was a simple and effective method to improve the hydrogen storage performance of Mg/MgH₂ system，which could provide active sites for H adsorption，dissociation，and diffusion of H₂ molecules in the process of hydrogen absorption and release of Mg/MgH₂，so as to improve its kinetic performance. In addition to catalyst doping，activation also played a key role in improving the hydrogen absorption and desorption reaction rates and cycling stability. Microwave was an emerging activation method in which not only was the energy absorbed by the dipole molecules and conductive electrons in a material and converted into heat，but also excited the surface electrons of the catalyst into a higher energy state which could change the path of the surface chemical reaction，such as promoting H dissociation. The microwave field could also reorient polar molecules，increasing the adsorption of reactants on the catalyst surface，thereby increasing the reaction rate. Therefore，the doping of catalysts with strong microwave absorption properties for modification could not only provide an active site for hydrogen absorption and release，but also use the various effects induced by its coupling with microwave to activate magnesium-based hydrogen storage materials and strengthen the dehydrogenation reaction process. In this study，graphene （G）-supported Fe₃O₄ nanoparticle （Fe₃O₄@G）was prepared and doped into magnesium powder via mechanical ball milling，followed by activation using microwave irradiation. The doping of Fe₃O₄/graphene composite in magnesium nanomaterials not only ensured effective dispersion of the catalyst and MgH₂ on graphene but also facilitated activation through the strong interaction between Fe₃O₄/graphene and microwaves. Furthermore，graphene could construct efficient thermal transport channels for the rapid dehydrogenation process due to its high thermal conductivity. The effects of different catalyst dosages，Fe₃O₄/graphene ratios，and microwave activation time on the hydrogen adsorption and dehydrogenation of Mg/MgH₂ were systematically studied. When studying the effect of microwave activation on the hydrogen absorption performance of the Mg-Fe₃O₄@G composite material，the activation time was investigated，and it was found that the hydrogen absorption kinetic performance and the maximum hydrogen storage capacity were remarkably improved by about 15% by microwave activation for 150 s. Compared with Fe₃O₄ and graphene single doping，Fe₃O₄@G composite doping could significantly improve the hydrogen storage performance of Mg. The best hydrogen storage performance was achieved when the doping amount of Fe₃O₄@G was 10 wt%，especially when the mass ratio of Fe₃O₄ to graphene was 6∶4. Mg-6Fe₃O₄@4G showed a high hydrogen storage capacity of 6.18 wt%. Johnson-Mehl-Avrami-Kohnogorov （JMAK）model was used to calculate the activation energy of hydrogen absorption and dehydrogenation to 56.7 and 79.89 kJ·mol⁻¹，respectively，which were 30%-50% lower than commercial Mg/MgH₂. The hydrogenation and dehydrogenation cycling performance of Mg-6Fe₃O₄@4G at 300 ℃ was investigated，and it was found that the capacity was maintained well after 10 cycles，with the capacity retention rate of 96%，demonstrating that the composite had good cyclic performance. The dehydrogenation process of MgH₂-6Fe₃O₄@4G could be greatly enhanced by microwave heating，in which the dehydrogenation rate could amount to 91% after 30 s and 95% at 35 s under 1500 W microwave irradiation. The results of four conventional hydrogenation followed by microwave dehydrogenation cycles showed that the average hydrogen storage capacity retention rate of Mg-6Fe₃O₄@4G composite was 97.5%，and the average dehydrogenation rate was 95.5%. The Mg-6Fe₃O₄@4G composite had good cyclic stability，and the dehydrogenation efficiency could be significantly enhanced by microwave radiation. In order to study the principle of improving the dehydrogenation performance by microwave heating，SEM analysis was conducted on the prepared composite material before and after microwave irradiation. It was found that the composite material was broken into smaller particles after microwave heating，and the surface of the particles became rougher，showing more pores and cracks，which not only reduced the particle size of the material，but also formed cracks. The formation of a new surface accelerated the adsorption and diffusion of hydrogen，thereby improving the kinetic properties of the material. This study provided a systematic reference to improving the hydrogen absorption and desorption kinetics of Mg/MgH₂ and developing a rapid dehydrogenation method which was featured by the enhancement of microwave heating.

Given the escalating global energy crisis，there is now a pressing need for a transition towards cleaner and more sustainable energy sources. In this regard，hydrogen energy has emerged as a frontrunner due to its environmentally friendly characteristics，high calorific value，and versatile applications. Proton exchange membrane fuel cells （PEMFCs）have garnered significant attention for their potential to drive this transition，particularly in both mobile and stationary hydrogen energy sectors. Their operational advantages，such as low temperature specifications，high power densities，and zero carbon dioxide emissions，position them as a key player in the future of clean energy technology. However，one of the challenges faced by PEMFCs is that the process of producing the fuel H₂ usually involves a water-gas shift reaction，resulting in some residual CO，which can be harmful to the platinum electrodes and cause irreversible damage. In response to this issue，the development of techniques such as preferential oxidation of CO （CO-PROX）has become increasingly crucial in effectively eliminating trace CO from hydrogen-rich gases，thus enhancing the performance and durability of PEMFCs in the long term. Pt-based catalysts are the most commonly used for CO-PROX，but considering the scarcity and high cost of the noble metals，the development of non-precious metal catalysts has become a research hotspot. Cu-based catalysts have been widely investigated because of their excellent catalytic performance in CO oxidation，while MnO₂ with its high oxygen mobility and oxygen storage capacity，has been widely used in oxidation reactions. Hence，Cu-Mn system catalysts will be the alternative choice for noble catalysts. In loaded catalysts，the role of the support is critical. The morphological diversity of the supports results in different exposed crystalline surfaces，which not only affects the redox properties of the supports themselves，but can also cause changes in the degree of interaction between the supports and the active components. Such changes in interaction will further alter the electronic structure and coordination environment of the active component，change its chemical state and distribution，and thus have a significant impact on the catalyst's reaction performance and reaction mechanism. In this study，α-MnO₂ nanowires （w），nanotubes （t）and nanorods （r）were successfully synthesized by a hydrothermal method and loaded with 1.5 wt% Cu by excess impregnation，the effect of support morphology and exposed crystal planes on the CO-PROX reaction properties on Cu/MnO₂ was also investigated. Powder X-ray diffraction （XRD），nitrogen adsorption-desorption，inductively coupled plasma atomic emission spectrometer （ICP-AES）and transmission electron microscope （TEM）were used to characterize the basic information of the catalyst structure. H₂-temperature programmed reduction （H₂-TPR）and O₂-temperature programming desorption （O₂-TPD）were used to compare the redox capacities of the catalysts. X-ray photoelectron （XPS）was used to analyze the chemical states of the elements，and in situ diffuse reflectance infrared Fourier transform spectroscopy （in situ DRIFTS）was used to investigate the reaction mechanism of Cu/α-MnO₂ with different morphologies. It was found that the reaction properties were strongly influenced by the morphology of the support and the exposed crystal planes. Cu/α-MnO₂-w was able to achieve complete CO conversion within a wide operating window of 100-250 ℃，while Cu/α-MnO₂-t only reached the highest conversion of 98% at 200 ℃. Cu/α-MnO₂-w further investigated the effects of H₂O and CO₂ on the performance of CO-PROX，and the results presented that the inhibition of CO oxidation by H₂O was more significant than CO₂，and the temperature for complete CO conversion was shifted to higher temperature of even up to 150 ℃. Characterization results showed that different morphologies of α-MnO₂ exposed different crystalline planes： nanowire （w），tube （t）and rod （r）shaped α-MnO₂，exposing （110），（200）and （300）crystalline planes，respectively. Differences in support morphology and exposed crystalline planes affected the state of Cu presence. No peaks associated with Cu species were observed in XRD，while TEM showed that Cu existed in different states on different morphologies of α-MnO₂： CuO particles were observed only on Cu/α-MnO₂-w，whereas lattice fringes of Cu species were not observed on Cu/α-MnO₂-t and Cu/α-MnO₂-r. Cu exerted a consistent effect on the α-MnO₂ with different morphologies： Cu provided additional CO adsorption sites （Cu⁺）and promoted the creation of Mn³⁺ and oxygen vacancies，favoring the activation of gas-phase oxygen. In addition，valence cycling between Cu²⁺/Cu⁺ and Mn³⁺/Mn⁴⁺ further aggravated the cycling of reactive oxygen species. However，the enhanced redox capacity of different forms of Cu/MnO₂ varied： Cu/α-MnO₂-w had the most enhanced oxygen supply capacity and the lowest reduction peak temperature （224 ℃）in H₂-TPR profiles； XPS showed that Cu/α-MnO₂-w had the highest Mn³⁺/Mn⁴⁺ content and the most oxygen adsorbed on the surface，and the smallest temperature difference between the surface lattice oxygen and the main body lattice oxygen was only 179 ℃ in the O₂-TPD. The reaction mechanism was explored by in situ DRIFTS，and the strongest CO adsorption was observed on Cu/α-MnO₂-w，which showed a significant red-shift of the CO adsorption peak （2108 cm⁻¹）on Cu/α-MnO₂-w compared with that on Cu/α-MnO₂-t （2132 cm⁻¹）. On Cu/α-MnO₂-w，the presence of H₂ promoted the generation of unstable bicarbonates and carbonate，whereas in Cu/α-MnO₂-t，H₂ only promoted the generation of carbonate intermediates that were not easily decomposed.

Ultra-high-speed laser cladding technology，as an advanced surface coating technology，has the advantages of low dilute rates，low thermal stress，little influences on the substrates，and high deposition efficiency，and has wide application prospects in improving the corrosion resistance and wear resistance of parts. 300M （40CrNi2Si2MoVA）steel，as the key materials of landing gear structures，is prone to damage and corrosion in the inherent contact of landing gears and in the face of high temperature，high humidity，and high salt environment. In order to solve the above problems，300M steel coatings were fabricated by ultra-high-speed laser cladding，and the effects of cladding speed on the microstructures and properties of the coatings were studied. The microstructures of the coatings were characterized by a scanning electron microscope （SEM），and the phase structures were characterized by an X-ray diffractometer （XRD），and the microhardness，wear resistance，and corrosion resistance of the coatings were characterized and tested by a Vickers microhardness tester，a friction and wear tester，and an electrochemical workstation. The results indicated that the defects of the coatings decreased and the dilution rates decreased from （35.2%±1.8%）to （24.8%±2.4%），and the average grain sizes of the coatings decreased from （5.8±1.6）to （3.2±1.1）μm with the increase of cladding speed from 1.8 to 40 m·min⁻¹. The coatings were mainly composed of martensite，carbides and retained austenite，and there was not significant difference in phase structures of coatings at different cladding speeds，which played a crucial role in improving the comprehensive properties of the coatings. The grain structures of coatings were refined，the reduction of pores and the distribution of elements was more uniform with the increase of cladding speed，which improved the mechanical properties and corrosion resistance of coatings，and compared with the substrates，the coatings had better comprehensive properties. The average microhardness，wear rates，and corrosion current density of substrates were HV （299.8±17.8），（5.63±1.06）×10⁻⁶ mm³·N⁻¹·m⁻¹ and 1.17×10⁻⁶ A·cm⁻²，respectively. The microhardness of the coatings increased，and the friction coefficients，wear rates and corrosion current density of the coatings decreased with the increase of cladding speed. Therefore，the wear resistance and corrosion resistance of the coatings were improved when the cladding speed increased from 1.8 to 40 m·min⁻¹. The coatings exhibited the best comprehensive properties，and the average microhardness，wear rates，and corrosion current density of coatings were HV （579.6±61.8），（0.84±0.41）×10⁻⁶ mm³·N⁻¹·m⁻¹，and 8.45×10⁻⁷ A·cm⁻² when the cladding speed was 40 m·min⁻¹.

The development of electronic devices has led to an increasingly complex electromagnetic interference （EMI）environment，posing potential health risks. Graphene，with its excellent mechanical，electrical，and thermal properties，emerges as a promising candidate for EMI shielding. However，its limited dielectric loss and lack of magnetism restrict its application in microwave absorption. Recent studies have shown that recombination of graphene with magnetic materials can effectively regulate its electromagnetic properties，enhancing microwave absorption performance. Therefore，it is crucial to study the structure of graphene adsorbed with magnetic atoms，as well as the influence of magnetic elements on graphene's electromagnetic properties. In this work，we investigated the crystal structure and electromagnetic properties of graphene adsorbed with three magnetic atoms （Fe，Co，and Ni）using the first-principles method based on density functional theory （DFT）. A 4×4×1 supercell was used for the pristine graphene structure，and a 3 nm vacuum layer was introduced in the z-direction to eliminate interlayer interaction. The magnetic atoms were adsorbed onto graphene at three sites： the hollow （H）site at the center of the hexagon，the top （T）site of the carbon atom，and the bridge （B）site between two carbon atoms. The adsorption energy，crystal structure，electronic band structure，magnetic moment，and dielectric constant of graphene adsorbed with Fe，Co，and Ni atoms were calculated using the Vienna Ab initio Simulation Package （VASP）code. Bader charge analysis was performed to reveal electron transfer between the magnetic atoms and graphene，and the adsorption energy was used to assess the stability of the adsorption structures. Our results revealed that the most stable configurations for magnetic atoms Fe，Co，and Ni on graphene were observed at the H site，which exhibited more negative adsorption energy and the lowest adsorption height. Pristine graphene exhibited a unique band structure where the valence band maximum （VBM）and conduction band minimum （CBM）met at the high-symmetry K point，forming a characteristic Dirac point at the Fermi energy level. Upon adsorption of an Fe atom，the band structure of the Fe@graphene system retained the Dirac points，but significant changes occurred near the Fermi level. Notably，the degeneracy of spin-up and spin-down bands was broken，and new flat valence and conduction bands emerged. For Co@graphene，the Fermi level crossed the valence band，inducing spin polarization in the bands. Additionally，new bands formed near the Fermi level. In contrast，the Fermi energy level of Ni@graphene remained located at the Dirac point，with no observed spin polarization. However，some new bands appeared near the Fermi level for Ni@graphene as well. The calculated density of states （DOS）and partial density of states （PDOS）revealed a broken spin-up/down symmetry for graphene adsorbed with Fe and Co atoms，indicating the presence of a magnetic moment. This was further confirmed by our calculations，which showed total magnetic moments of 2.01 and 1.12 μB for Fe@graphene and Co@graphene，respectively. The PDOS results indicated that the peaks near the Fermi energy level were mainly attributed to the d orbitals of magnetic atoms and the p orbitals of carbon atoms. In contrast，Ni@graphene exhibited a total magnetic moment of 0 μB. The PDOS showed three peaks below the Fermi level，arising mainly from the Ni-d orbital. Additionally，the PDOS curves demonstrated that the bands near the Fermi level were dominated by the adsorbed magnetic atoms，while the contributions from carbon atoms became significant below –2.0 eV. Orbital hybridization between the d orbitals of adsorbed magnetic atoms and the p orbitals of carbon atoms occurred near the Fermi level，resulting in new bands. The adsorption of magnetic atoms significantly impacted the electron distribution of graphene. Bader analysis revealed charge transfers of 0.665e，0.571e，and 0.464e from Fe，Co，and Ni to graphene，respectively. This charge transfer was further confirmed by the charge density difference analysis. Additionally，the electron localization function displayed overlap between the charge clouds of adsorbed atoms and carbon atoms，suggesting the presence of covalent bonding. Our investigation further explored how adsorbed magnetic atoms influenced graphene's dielectric properties. The intrinsic static dielectric constant of graphene was 4.45. After adsorption of Fe，Co，and Ni atoms，the static dielectric constants increased to 7.52，7.61，and 4.66，respectively. This increase indicated that magnetic atoms could enhance the polarization intensity of graphene. Compared to pristine graphene，both the real and imaginary parts of the dielectric constants were significantly enhanced after adsorption of Fe，Co，and Ni atoms. In the range of 0–0.68 eV，the maximum values of the real part reached 8.12，4.74，and 6.31 for graphene adsorbed Fe，Co，and Ni，respectively. As the energy increased，the real part of the dielectric constant became consistent with graphene. Similarly，the maximum values of the imaginary part of the dielectric constant for graphene adsorbed with Fe，Co，and Ni were 6.25，4.29，and 6.10，respectively. Interestingly，the first peaks of the imaginary parts of the dielectric functions for Co@graphene and Fe@graphene shifted toward the low-energy region，while the first peak for Ni@graphene shifted toward the high-energy region. This behavior could be attributed to the orbital hybridization between the d-orbitals of the magnetic atoms and the p-orbitals of the carbon atoms in graphene. Furthermore，our results showed that the concentration of magnetic atoms was crucial for optimizing the dielectric properties and the range of attenuation frequency. In conclusion，our study demonstrated that the electric，magnetic，and dielectric properties of graphene could be regulated by adsorbing magnetic atoms. This work provided theoretical guidance for the research and application of graphene in the field of electromagnetic shielding.

Due to the pressing demand for clean energy，nuclear energy development has received a lot of attention lately. Unfortunately，the extraction and use of nuclear energy result in the large-scale discharge of wastewater containing uranium. Hexavalent uranyl cation （UO₂²⁺），an extremely poisonous substance，is present in aqueous solution as uranium（Ⅵ）. Because of uranium（Ⅵ）'s high water solubility，it poses a long-term risk to human health as well as the health of other organisms through bioaccumulation. Thus，it is essential to remove soluble uranium from wastewater in order to lower the danger of uranium（Ⅵ）. Various methods，such as chemical precipitation，membrane separation，biochemical/chemical reductive，ion-exchange，and adsorption have been used to adsorb and enrich uranium. Among these，adsorption technology has garnered a lot of interest because of its cost-effective and simple operation. Until now，various adsorbents such as metal-organic framework materials，various adsorbents such as carbon-based material，clay mineral covalent organic framework-based materials，and nanoscale zero-valent iron have been developed and applied for uranium（Ⅵ）removal. Recently，layered double hydroxides （LDHs）have attracted wide attention in catalysis，electrochemistry，photochemistry，magnetization，biomedical science，elastomer composites，and environmental decontamination. Multiple alternative metal cations can regulate the host layer's composition. Through substitution，the interlayer anions may improve the anion exchange capacity and cation adsorption capability. Ion-exchange of cations or removal of negatively charged pollutants was facilitated by the positively charged layer. LDHs have been identified as potential uranium removal adsorbents due to their benefits of low cost，high chemical stability，high layer charge density，substantial ion exchange capacity，and ease of modification. A lot of interest has also been piqued by the adsorption of uranium（Ⅵ）by LDHs. To reach the goal of creating advanced materials with specific functions and directed applications，functional groups can be intercalated into LDHs to modify their structure. Furthermore，as the material's LDH level increased，so did its resistance to erosion. Metal ions within LDHs exhibit an electrostatic attraction towards the negatively charged intercalating anions，leading to their tendency to aggregate. Moreover，these nanoscale particles readily agglomerate due to the influence of van der Waals forces. As a result，the adsorption efficiency is decreased and the adsorption sites are only partially exposed. Concurrently，this material has less-than-ideal mechanical qualities due to its tendency to attrition following usage in wastewater. Moreover，they are not easily recovered. Its structure needs to be strengthened in order to increase its stability and apply to more areas. Attapulgite （ATP）is a hydrated octahedral-layered magnesium-aluminum silicate mineral containing an abundance of structural hydroxyl groups. Because of its huge surface area and rod-like structure，ATP has a high metal ion sorption capability. Notably，ATP's crystalline structure includes three-dimensional chains，which guarantee both its complete dispersion in the presence of external pressures and its high stability in solution. Its needle-like bundles disintegrate into a disordered network that thickens the system and binds the liquid when dispersed in water. Therefore，by combining Fe-Mg-LDHs with ATP，the hydrophilic characteristic of ATP can be used to increase the Fe-Mg-LDHs active sites and decrease the likelihood of agglomeration. Additionally，ATP improves the Mg-Fe LDHs' microstructure，allowing for greater reuse. In this study，ATP/Mg-Fe LDHs particles were applied as an adsorbent for uranium（Ⅵ）extraction from wastewater. The hydrothermal approach of synthesizing ATP/Fe-Mg-LDHs offered the benefits of low cost，easy synthesis，and high uranium adsorption capacity. The Fe-Mg-LDHs' polymerization was significantly reduced by the presence of ATP. ATP/Fe-Mg-LDHs showed great reusability and a high adsorption capability. The optimal adsorption conditions for this adsorbent，uranium affinity mechanism，and behavior during uranium adsorption were comprehensively explored. Additionally，we studied the cyclic stability，cation impact，anion impact，and adsorption capacity of the ATP/Fe-Mg-LDHs during uranium extraction. The ATP/Fe-Mg-LDHs characterization and adsorption ability performance were comprehensively described in this study. ATP was negatively charged，whereas Fe-Mg-LDHs were positively charged，and the two attracted each other and combined solidly to produce ATP/Fe-Mg-LDHs with an electrical property of −0.27 mV. The optimal adsorption conditions for ATP/Fe-Mg-LDHs were as follows： the pH of solution，use level of ATP/Fe-Mg-LDHs，temperature，and adsorption time were 3.0，0.05 g，room temperature （25 ℃），and 20 min，respectively. Characterization techniques showed that the adsorption of uranium by the ATP/Fe-Mg-LDHs was mainly related to hydroxyl，carbonate and electrostatic adsorption with the occurrence of a redox process. The optimal pH of the adsorption environment was 3.0 and the adsorption efficiency reached about 97%； ATP/Fe-Mg-LDHs had high selectivity and was not easily affected by the environment. The adsorbent showed good cycling stability，and the adsorption effect did not decrease significantly after five experiments. Furthermore，the cost-effectiveness of its production presented significant potential for applications in treating uranium-containing wastewater and in uranium recovery.

At present，most enterprises use electrowinning process to produce zinc. In this process，the power consumption of electrolytic zinc accounts for a high proportion，and there are many influencing factors，so it is difficult to reduce the electrical energy consumption of this step. Under the background of energy saving and carbon reduction transformation in the non-ferrous metal industry and improving the utilization efficiency of energy resources，the zinc smelting industry undertakes the important task of saving energy and reducing production costs. The lead-zinc industry standard conditions require that the direct current consumption of electric zinc in the process of the enterprise is not higher than 3050 kWh·t⁻¹，which makes it urgent to reduce electrical energy consumption. In the process of zinc electrowinning，reducing power consumption means that the cell voltage and the current efficiency of the cathode need to be strictly controlled. The ion concentration in the electrolyte has a great influence on the cell voltage and the current efficiency of the cathode，and it is difficult to eliminate. The influence of each ion on the cell voltage and the current efficiency of the cathode is also different. Ca²⁺ and Mg²⁺ are alkali metal ions. Calcium and magnesium salts make it difficult to separate and filter the pulp during leaching，and are easy to crystallize during the electrowinning process，which makes the equipment pipeline blocked，which mainly affects the viscosity of the solution and the resistance of the electrolyte. In the electrolyte，on the one hand，Mn²⁺ can make the anode surface form dense MnO₂，which makes the electrode difficult to be corroded，therefore，it is necessary to add appropriate Mn²⁺ in the electrolyte. On the other hand，excessive Mn²⁺ in the electrolyte will aggravate the effect of oxygen evolution reaction and affect the quality of cathode zinc precipitation，which mainly affects the anode reaction and the side reaction in electrowinning. Too low concentration of Zn²⁺ in the system will cause concentration polarization near the electrode，and too high content will reduce the distance between ions，which will reduce the conductivity of the solution and eventually lead to the increase of the cell voltage. This phenomenon is contrary to the concentration of sulfuric acid. The higher the concentration of sulfuric acid in the system，the higher the conductivity of the solution，but at the same time，the higher concentration of sulfuric acid will aggravate the hydrogen evolution reaction and even dissolve the precipitated zinc. In this paper，the effects of different sulfuric acid concentration，zinc ion concentration，manganese ion concentration，magnesium ion concentration，calcium ion concentration，and electrolyte temperature on the cell voltage，cathode/anode potential，and solution resistivity in the process of zinc electrowinning were systematically studied. The experimental results showed that when other variables were constant，the cell voltage and cathode/anode potential decreased with the increase of sulfuric acid concentration. With the increase of Zn²⁺ concentration，the cell voltage and cathode potential of the system did not fluctuate significantly，indicating that Zn²⁺ had little effect on the cell voltage in this concentration range. In the experimental range，with the increase of Mn²⁺ concentration，the potential of cathode and anode gradually increased and then decreased，but the amplitude was different，and the cell voltage rose first and then decreased，the variation was within 20 mV. With increasing Mg²⁺ concentration，the cell voltage rose from 3.08 to 3.18 V，accompanied by a shift in the cathode potential from –1.55 to –1.6 V and an increase in the anode potential from 1.5 to 1.54 V. When the temperature continued to rise，the cell voltage decreased，and the cathode/anode potential changed less； the cell voltage and cathode/anode potential did not change significantly with the increase of calcium ion concentration. The experimental results showed that the satisfactory reaction conditions for zinc electrowinning in this electrolyte concentration range were as follows： H₂SO₄ concentration was 150 g·L⁻¹，Zn²⁺ concentration was 40 g·L⁻¹，Mn²⁺ concentration was 2 g·L⁻¹，Mg²⁺ concentration was less than 15 g·L⁻¹，Ca²⁺ concentration was less than 0.5 g·L⁻¹，and electrolyte temperature was 40 ℃.