Abstract:Objective Enhancing the thermal decomposition of ultrafine ammonium perchlorate(AP)is a primary method to increase the burning rate of solid propellants.Current catalytic approaches typically employ transition metals,transition metal oxides,ferro-cene,and ferrocene derivatives,yet these conventional catalysts present significant limitations.The addition of transition metals and oxides may compromise processing performance,and the incorporation of ferrocene derivatives into ultrafine AP exhibits high mechanical sensitivity,posing safety risks during propellant manufacturing.These challenges have driven the need for safer,more efficient combustion catalysts with reduced sensitivity.In recent years,metal-organic framework(MOF)-based catalysts have shown significant progress.By combining different metal centers with organic ligands,it offers precise control over material characteristics,showing great application potential.Moreover,bimetallic cobalt-iron(Co-Fe)MOFs have attracted wide attention for their superior catalytic activity and stability compared to single metal MOFs,achieved through Co-Fe synergistic effects.In this study,to improve the burning rate of solid propellants,the zeolitic imidazolate framework-67(ZIF-67)is modified by introducing ferrocene carboxylic acid(FcA)as an Fe-containing organic ligand,partially replacing the low-activity organic ligand 2-methylimidazole.Through the Co-Fe bimetallic synergy,this study investigates the catalytic effects of ZIF-67 on AP thermal decomposition,providing foundational data and support for developing high-performance solid propellants with optimized burning rates. Methods To address the demand for high-buming-rate propellants,FcA-modified ZIF-67 with varying Fe contents(ZIF-67@25％FcA,ZIF-67@50％FcA,and ZIF-67@100％FcA)was synthesized through stirring and ultrasonication.The microstructure and crystal structure of the modified ZIF-67 were characterized using scanning electron microscopy(SEM),X-ray diffraction(XRD),and Fourier transform infrared spectroscopy(FTIR).The catalytic effects on AP thermal decomposition were investi-gated via thermogravimetry analysis-differential scanning calorimetry(TGA-DSC),while the impact on the burning rate of AP-based solid propellants was assessed using a laser ignition setup. Results and Discussion The modified ZIF-67 particles exhibited a uniform dodecahedral morphology with a particle size of approximately 2 μm.Among all the modified products,ZIF-67@100％FcA demonstrated superior catalytic performance.It reduced the high-temperature decomposition peak temperature of AP to 312 ℃,increased the apparent decomposition heat by about 1.5 times,and enhanced the burning rate of AP-based solid propellants by 13.3％at 7 MPa in an argon atmosphere. Conclusion The introduction of FcA significantly enhances the catalytic performance of ZIF-67 without notably impacting the mechanical sensitivity of solid propellants.Compared to the baseline formulation,the incorporation of ZIF-67 resulted in a 4.8％increase in burning rate,while ZIF-67@100％FcA achieved a more substantial 13.3％enhancement,demonstrating the effectiveness of this modification.Previous studies have shown that MOFs exhibit better catalytic performance when metal oxides form in situ during heating compared to direct addition.As a Co-based MOF with self-assembled 2-methylimidazole as the organic ligand,ZIF-67 benefits from the unique advantages of MOF materials,including unique microporous structures,high chemical tunability,and excellent catalytic properties,which are particularly effective for promoting AP decomposition.

Abstract:Significance In the context of global environmental protection and sustainable development,the efficient utilization of biomass resources has become a research hotspot.This study conducts an in-depth exploration of efficient preparation methods for biomass-derived activated carbon,which holds significant practical importance.Biomass,as a renewable and abundant resource,has the potential to be transformed into high value-added activated carbon materials.The specific impacts of activa-tion processes on the properties of biomass-derived activated carbon are crucial factors that determine its performance in various applications.Through a comparative analysis of physical and chemical activation mechanisms,this research aims to provide a solid scientific foundation for the widespread application of biomass-derived activated carbon across multiple fields.It is antici-pated that this study will facilitate the rational utilization of biomass resources,reduce environmental pollution,and drive the development of green and sustainable industries. Progress This study presents a comprehensive review of the preparation process of biomass-derived activated carbon.Physical activation,which mainly entails treatment with high-temperature gases such as steam and carbon dioxide,is a complex physical-chemical process.During this process,the gases penetrate the biomass matrix,inducing the internal structural rearrangement and facilitating gas diffusion.This physical action leads to the formation of a large number of micropores and mesopores,signifi-cantly increasing the specific surface area and optimizing the pore structure of the activated carbon.The well-developed pore structure provides more active sites for adsorption,thereby enhancing its adsorption capacity.Chemical activation,in contrast,employs chemical reagents such as alkali metal salts and acids to react with carbon precursors.These reagents interact with bio-mass at elevated temperatures,breaking chemical bonds within the biomass and promoting the formation of a porous structure.Moreover,chemical activation enhances the specific surface area of carbon materials and optimizes the pore structure.More importantly,it introduces specific functional groups onto the surface of the activated carbon.These functional groups,such as carboxyl,hydroxyl,and amino groups,interact with target pollutants through hydrogen bonding,electrostatic interaction,and chemical complexation,enriching the surface chemical properties and improving adsorption selectivity and efficiency.Further-more,the study comprehensively summarizes the substantial impacts of activation processes on specific surface area,pore struc-ture,functional group distribution,and the overall adsorption performance. Conclusion and Prospects Future research should prioritize the continuous optimization of preparation processes for biomass-derived activated carbon,highlighting the development of more efficient,environmentally friendly,and cost-effective activation techniques.Through in-depth and meticulous studies of activation mechanisms,it is expected that biomass-derived activated carbon materials with outstanding adsorption performance,high stability,and broad applicability can be developed.Such advances will not only address the urgent needs of current applications but also offer strong material support for emerging fields.

Abstract:Objective Rib spalling is a sudden and frequent issue in coal mining operations,often caused by the working conditions of the scraper conveyor.It leads to localized bulk material accumulation and impacts the conveyor system.This study investigates the effects of rib spalling on coal bulk material and the dynamic performance of scraper conveyor's chain drive system.By examin-ing variations in rib spalling strength and the falling posture of crushed material,this study aims to reveal their effects on system forces and stability,providing theoretical support for the design optimization of scraper conveyor. Methods In this study,a fractured rib spalling model was constructed using the discrete element method(EDEM)to simulate the falling process of crushed coal particles and their interaction with surrounding structures.The scraper conveyor was modeled using the multibody dynamics(MBD)method to capture the dynamic response of the chain drive system under impact loading.Then,a rigid-discrete coupling simulation was performed to simultaneously track bulk fragmentation and the resulting force responses.To represent typical coal wall degradation scenarios,three rib spalling strength levels were simulated using the rock integrity coefficient and a quasi-rock strength estimation method.Three distinct falling postures,including normal,reverse,and vertical falls,were considered to evaluate their influence on contact positions and force transmission.Finally,the integrated models were used to obtain the numbers of crushed particles and key dynamic parameters,such as scraper and chain forces in multiple directions,enabling a quantitative analysis of system behaviors under varying spalling conditions. Results and Discussion The results showed that lower rib spalling strength led to more severe crushing,with a correlation coeffi-cient of-0.99 between spalling strength and the number of crushed particles.After impact,scraper forces increased to 874.5,1 843.4,and 692 N,respectively,across the three different spalling strength levels,eventually leading to logging.This was due to the accumulation of fine particles between the scraper and the trough,which caused significant force fluctuations in the z-and x-directions.Among the different falling postures,vertical falls caused the smallest spalling volume.The posture of the fall-ing material mainly influenced the dynamic response through changes in impact direction.Normal and reverse falls caused sig-nificant impacts in the z-direction between the scraper and the chain ring.Vertical falls caused impacts on the central plate,leading to chain expansion on both sides and affecting x-direction force transmission.The blockage of the gap between the cen-tral plate and chain ring by fine particles generated during crushing was the main cause of x-direction force variation. Conclusion This study reports the effects of different rib spalling strengths and falling postures on coal bulk crushing and dynamic behavior of the scraper conveyor.It is found that the lower rib spalling strength leads to more severe crushing,with the most significant force responses in the z-direction of the scraper conveyor.Both the position and posture of falling particles affect the stability of the chain drive system by influencing the entry of fine particles into critical components.Specifically,low-strength rib spalling and asymmetric falling postures severely exacerbate force fluctuations in the system.The research results provide a theoretical basis for optimizing the design and operation of scraper conveyor.

Abstract:Objective To solve the problems of significant efficiency reductions and significant drops in gas processing capacity that occur in cyclone separators during large production fluctuations and unit start-up and shutdown stages,which leads to an increase in par-ticulate emissions and deterioration of product quality. Methods The maximum load(upper operating limit)of the unit or the maximum gas flow rate of the cyclone separator was deter-mined,which served as the basis for separator design.Then,real-time monitoring of the pressure differences between the inlet and outlet of the separator was conducted using pressure sensors.Utilizing this data,automatic adjustments of the inlet valve or bypass pipeline were triggered to compensate for reductions in process gas volume.Finally,a laboratory simulation system was established to verify the feasibility and effectiveness of the proposed scheme. Results and Discussion Two gas replenishment schemes were designed:direct fresh gas replenishment and recycled separator exhaust gas replenishment.An automatic control module was established to regulate gas replenishment.During laboratory simu-lations,a cyclone separator with a diameter of 300 mm was used.The test results showed that,without gas replenishment,the separation efficiency-gas volume rate curve presented an arch shape,peaking at 94.7％(measured with talc powder with an average particle size of 12 um)at a gas flow rate of approximately 1 000 m3/h,and the corresponding pressure drop reached 2 100 Pa.The separation efficiency varied greatly with changes in inlet gas volume rate,indicating strong sensitivity to gas vol-ume fluctuations.During gradual decreases in the process gas volume rate from 1 000 m3/h to 300 m3/h,the proposed system automatically replenished gas to maintain the target pressure drop of 2 100 Pa,and the separation efficiency remained stable at 94.7％.Under replenishment conditions,the relationship curve between separation efficiency and gas volume(gas velocity)transitioned to a nearly horizontal straight line. Conclusion The automatic gas replenishment at the separator inlet effectively mitigates efficiency loss when the process gas vol-ume decreases,ensuring consistent operation and maintaining maximum efficiency.By coupling a negative feedback control module driven by real-time pressure drop signals,the automatic control and intelligentization of the cyclone separator are enhanced.The proposed scheme is simple and effective,achieving both energy savings and emission reductions.

Abstract:Significance Energy storage,including mechanical,electromagnetic,and electrochemical energy storage,has garnered sub-stantial scientific and technological attention due to its great application potential in material processing,chemical and biomo-lecular sensing,security,and other industrial sectors.Specifically,electrochemical energy storage is largely employed in aero-space,power systems,electric vehicles,and portable electronic products,owing to their mature technology and broad commer-cial applicability.In the past decades,electrochemical energy storage devices have advanced substantially,accelerated by machine learning-assisted material discovery and advanced operando characterization techniques.These innovations have pro-vided an ideal platform for lithium-ion battery(LIB)research and numerous studies have been conducted on cathode and anode materials.However,LIBs still fail to offer truly sustainable and universally accessible energy storage solutions,primarily because of unresolved safety concerns and environmental issues.In this context,aqueous zinc-ion batteries(AZIBs)have emerged as a highly promising alternative.AZIBs are renowned for their excellent safety,abundant resource availability,and reliable chemical stability.These advantages make them a focal research topic for energy storage in recent years. Progress To date,three primary interface-regulation mechanisms have been developed forZn anodes in AZIBs:(1)regulating Zn deposition/stripping kinetics,(2)selective orientation growth of crystal planes,and(3)constructing artificial solid electro-lyte interface(SEI)layers.The earliest approach,uniform Zn deposition via a 3D porous structure,was first introduced in 2014 by Debra R.Rolison et al.,who created a 3D zinc sponge anode from zinc powder and emulsion.This anode featured a porous,integral,and aperiodic structure.Subsequently,different 3D Zn sponge anodes were introduced into AZIBs with improved cycle stability and safety.However,all these anodes were constrained by connectivity loss in powder-composite electrodes,leading to localized high current density and dendrite formation,as reported by Chamoun et al.using hyper-dendritic nanoporous Zn foam.In 2019,the technique evolved to plated Zn anodes on different substrates.Su et al.introduced holey metal nanotube membranes as high-performance electrode scaffolds for energy storage.Since then,numerous efforts have been made to optimize 3D Zn anodes through SEI engineering,alloying strategies,and 3D printing.A notable achievement was reported by Zhang et al.,where a new type of 3D Zn anode was fabricated by combining 3D printing,chemical deposition,and electrodeposition.More recently,in 2022,Gu et al.designed a surface-engineered forest-like 3D Zn-Cu alloy anode in dual-cation electrolytes,which effectively regulated plating/stripping kinetics and inhibited dendrite growth on the anode surface.Subsequently,the Zn alloys were applied in AZIBs.To simplify the electroplating process,Fan et al.used an alternative 3D Zn-Sn-Pb alloy anode to establish a single Zn metal anode that eliminated both dendritic growth and corrosion reactions. Conclusions and Prospects The past decade has seen great progress in AZIBs,enabling a range of new applications.Different mechanisms,such as 3D porous structures,surface-coating technologies,and Zn alloying strategies,have been incorporated into the 3D Zn anode design with optimized cycle stability and safety.However,traditional Zn anode systems still suffer from uncontrolled Zn dendrite growth,intensified hydrogen evolution reactions(HER),and corrosion/passivation layer rupture.These issues lead to poor Coulombic efficiency and limited cycle life,particularly due to the non-uniformity of interfacial ion transport at high current densities(＞40 mA/cm2)or deep discharge depths(＞80％DOD).To address these issues,the develop-ment of advanced 3D Zn anodes represents a key research direction in the future.In addition,the volumetric energy density of AZIBs is significantly lower than that of LIBs,necessitating improvements in techniques and design.Beyond structural optimiza-tion,in-depth interdisciplinary applications of AZIBs are also a crucial research direction.

Abstract:Objective Photopolymerization is a widely utilized technique across various fields due to its environmentally friendly and effi-cient characteristics.During the process of photopolymerization,photoinitiators(PIs)are essential in determining the excitation wavelength,polymerization type,polymerization rate,and the final material properties.However,conventional PIs are hin-dered by two photophysical phenomena,the inner filter effect,where PIs and their photodegradation byproducts concentrated at the material's surface absorb most of the incident light,and Rayleigh scattering,where a significant portion of incident light is scattered on the surface of a photopolymerization system.These effects prevent subsurface PIs from receiving sufficient activa-tion energy for photolysis,leading to reduced polymerization efficiency,shallow cure depths,and impaired material perfor-mance.Additionally,the small molecules generated from conventional PIs may migrate within the cured material,potentially leading to toxicity.To address this issue,low-migration,multiband responsive polymerizable PIs have been developed. Methods A photopolymerizable methacrylate phenacyl phenothiazinium salt(Acry-P-PTh)was synthesized by incorporating acrylic ester groups.Its structure,photophysical properties,photochemical behavior,migration ratio,and thermal stability were investigated using ultraviolet-visible absorption(UV-Vis)spectroscopy,real-time infrared(RT-IR)spectroscopy,and differential scanning calorimetry(DSC). Results and Discussion UV-Vis analysis revealed that Acry-P-PTh was responsive to ultraviolet(UV),visible,and near-infrared(NIR)light,with the peak absorption wavelength shifting to 520 nm,a 5 nm redshift compared to phenacyl phenothi-azinium salt(P-PTh).Photopolymerization kinetics demonstrated that Acry-P-PTh effectively initiated both free radical and cat-ionic polymerization.Under 365 nm,405 nm,and 850 nm irradiation,Acry-P-PTh generated benzoyl radicals and Br∅nsted superacids through C-S bond homolysis.This dual initiation mechanism enabled the polymerization of both acrylate monomers,trimethylolpropane triacrylate(TMPTA),and cationic monomers,EPOX,achieving excellent initiation performance in hybrid systems compared to single-monomer resin systems.Specifically,under 365 nm light irradiation,the final free radical conver-sion rate exceeded 50％,and the final cationic conversion rate exceeded 40％;under 405 nm light irradiation,the final free radi-cal conversion rate exceeded 45％,and the final cationic conversion rate exceeded 45％.Notably,under 850 nm light,EPOX cationic polymerization achieved a 40％conversion rate within 30 min.Migration studies confirmed that Acry-P-PTh exhibited low migration,with post-curing migration ratios lower than those of P-PTh,measuring 4.9％for the free radical system and 3.5％for the cationic system.Thermal stability analysis further revealed high thermal resistance,with polymerization tempera-tures for free radical and cationic polymerization being 233 ℃ and 78℃,respectively.These properties make Acry-P-PTh a promising material for various applications,such as food packaging and biomedicine manufacturing. Conclusion The synthesized Acry-P-PTh demonstrates broadband absorption across the ultraviolet-visible-near-infrared(UV-Vis-NIR)spectrum.Compared to P-PTh,Acry-P-PTh shows reduced low migration ratio.When mixed with Acry-P-PTh with TMPTA and EPOX monomers,the photocurable system is able to resist higher thermal polymerization temperatures,demonstrat-ing excellent thermal stability.In conclusion,Acry-P-PTh,as an advanced photoinitiator,holds significant potential for practi-cal applications.

Abstract:Significance This study analyzes the concept,scientific connotation,and current industrial applications of powder technology for carbon neutrality and evaluates its role in achieving global carbon neutrality goals. Progress A systematic overview is provided of the applications of powder technology in energy conservation and emission reduc-tion,carbon capture,utilization,and storage(CCUS),and renewable energy utilization.The study summarizes its emission reduction effects in industries such as construction materials,chemicals,and energy,as well as its positive impact on environ-mental engineering,particularly in dust control and wastewater purification. Conclusions and prospects Although powder technology has made certain progress in promoting energy conservation and emis-sion reduction in industrial production,it still faces challenges in technological innovation,policy support,and market mecha-nisms.Future research should focus on developing more efficient and cost-effective powder technologies for carbon neutrality,strengthening international cooperation,improving market mechanisms,and raising public awareness to promote the application of powder technology in achieving carbon neutrality goals.The future development of carbon-neutral powder technologies should focus on the following key areas:1)Technological Innovation:Continuous innovation in powder technologies is essential for developing more efficient and cost-effective energy-saving and emission-reduction methodologies.This includes the creation and implementation of advanced adsorbent materials and membrane separation techniques,which can significantly enhance energy utilization efficiency in industrial processes and reduce carbon emissions.2)Policy Support:Strengthening government policy support for carbon-neutral powder technologies is crucial.This can be achieved through the provision of fiscal subsidies,tax incentives,and green financial mechanisms to incentivize enterprises to invest in and adopt low-carbon technologies.3)Market Mechanism:Establishing a robust carbon emission rights trading market and implementing a rational carbon pricing mechanism is essential for facilitating the market-oriented application of carbon-neutral powder technologies.4)International Cooperation:Enhancing international technical exchanges and cooperation is vital for sharing successful experiences and technologies,thereby promoting global efforts toward carbon reduction.5)Public Participation:Increasing public awareness of carbon neutral-ity and encouraging participation from all sectors of society in carbon reduction actions can foster a collaborative societal atmo-sphere dedicated to achieving global carbon neutrality.6)Interdisciplinary Research:Promoting interdisciplinary integration of powder technologies with environmental science,energy science,and other fields is essential for conducting cross-disciplinary research.This approach can generate innovative ideas and comprehensive solutions to support carbon neutrality initiatives.

Abstract:Objective Temporary prescription preparation is key component of personalized pharmaceutical services,characterized by indi-vidualized formulations and diverse dosage forms.However,the strong odor and taste of traditional Chinese medicine(TCM)often reduce patient acceptance and utilization rates,limiting the formulation options for temporary prescription.Tablets,one of the most commonly used solid dosage forms,offer advantages such as color and taste masking and high drug loading.Among tab-let preparation methods,direct powder compression is preferred for its simplicity and efficiency,making it suitable for temporary prescription.However,the complexity and hygroscopicity of TCM powders pose significant challenges during tablet compres-sion,including cracking,sticking,and structural instability.These issues highlight the need for careful formulation design.Building on previous research that identified basic tablet-forming formulations,the study aims to evaluate the formability and physical stability of TCM temporary prescription tablets prepared using different base formulations.The findings will provide guidance for optimizing formulations and improving storage conditions for temporary prescription tablets. Methods In this study,two base formulations were investigated for their compressibility and compactibility using the direct pow-der compression technique.Tensile strength and disintegration time were used as key assessment indicators.Given that tempo-rary prescription preparations are not subjected to prolonged transportation and storage,the quality standards were set according to the Pharmacopoeia of the People's Republic of China:a minimum of tensile strength of 1.7 MPa and a disintegration time of less than 60 min.To assess physical stability,tablets were stored at a relative humidity of 60％and a temperature of 25℃.Key parameters,including tablet weight change,axial and radial expansion change,tensile strength,and disintegration time,were monitored to evaluate stability over time. Results and Discussion Using the expert formulation design system developed in previous research,two formulations(Formula-tion 1 and Formulation 2)suitable for the direct compression of TCM compound powders were successfully screened.Tablets prepared with both formulations exhibited good formability and met quality requirements.During the stability study,both formu-lations experienced different degrees of axial and radial expansion.Tablets prepared under controlled tensile strength showed more pronounced expansion during storage than those prepared under controlled compression force.The tensile strength of most tablets remained relatively stable or slightly increased at week 1,though a few showed a more pronounced decrease followed by an increase.Notably,Formulation 2 demonstrated greater tensile strength fluctuations than Formulation 1.Despite these varia-tions,all tablets maintained tensile strength values above 1.7 MPa throughout the 4-week stability study period,ensuring their suitability for handling and administration.Additionally,the disintegration time of most tablets stabilized after 1 week of stor-age,indicating that moisture absorption reached equilibrium with ambient humidity. Conclusion Moisture content is an important factor affecting product stability,especially for hygroscopic TCM powders.Tablets stored in high-humidity environments tend to absorb moisture to reach equilibrium with storage conditions.Storage humidity affects weight changes in tablets and leads to varying degrees of axial and radial expansion.These structural changes can affect inter-particle bonding,thereby influencing the internal structure and quality of the tablets.However,once equilibrium is reached,the physical properties of the tablets tend to stabilize.By utilizing a systematic formulation design approach,temporary prescription tablets with acceptable stability can be rapidly screened and developed.

Abstract:Objective Kaolin,characterized by its unique layered structure and strong ion exchange capacity,has been widely used in envi-ronmental pollution prevention and wastewater treatment.However,coal-serieskaolin,often discarded as solid waste during coal processing,remains severely underutilized.To enhance its tilization rate,modification treatments are necessary. Methods In this study,coal-series kaolin from Inner Mongolia was ball-milled and impregnated with alkali,followed by modifi-cation in a polyhydroxy-aluminum solution,which was prepared using different ratios of Al3+and OH-.The adsorption capacity of modified kaolin for fluoride(F-)was evaluated.Additionally,influencing factors,including adsorption time,initial solution pH,initial concentration of F-,and the adsorption isotherms and kinetics,were examined to analyze the effects of adsorption conditions on its adsorption performance. Results and Discussion The kaolin samples after polyhydroxy-aluminum modification were characterized byX-ray diffraction(XRD),N2 adsorption-desorption,transmission electron microscopy(TEM),and energy dispersive spectroscopy(EDS).The results showed that the specific surface area of modified kaolin increased significantly while its structure remained largely unchanged.The removal rate for F-reached 95％at a F-concentration of 10 mg/L,20 times higher than that of raw kaolin(5％),demonstrating enhanced F-adsorption performance.Adsorption condition analysis revealed that the optimal F-adsorption perfor-mance occurred at a solution pH of 7.0 to 8.0,a thermodynamic temperature of 298 K,a shaking time of 100 min,and a shak-ing frequency of 200 r/min.The adsorption mechanism was also explored through the evaluation of adsorption kinetics and iso-therm models.The adsorption isotherm data conformed to the Freundlich model,while the adsorption kinetics followed the pseudo-second-order model. Conclusion In this study,a polyhydroxy-aluminum modification method is used to enhance the F-adsorption capacity for coal-serieskaolin.This approach has the advantage of simple preparation process,low cost,low energy consumption,and environ-mental friendliness.It can effectively improve the adsorption performance of coal-series kaolin for F-ion from water.This approach enhances the effective utilization of coal-series kaolin waste resources and provides a cost-effective adsorbent for treat-ing F--containing water,thereby achieving waste treatment through waste utilization.Future research can explore the recycling potential of polyhydroxy-aluminum-modified kaolin adsorbents to reduce water treatment costs.

Abstract:Objective Hydrophilic hydrogels are essential in evaporative cooling applications.By utilizing waste heat generated by solar cells,the hydrogels can drive internal moisture evaporation and reduce their operating temperature.However,the inherently low thermal conductivity often limits their cooling effectiveness.To address this limitation,thermally conductive fillers such as carbon nanoparticles can be incorporated into hydrogel matrices to enhance both thermal transport and moisture regulation.Car-bon nanomaterials,known for their exceptional nanoscale thermal conductivity,offer a promising approach to enhancing hydro-gel performance.This incorporation not only enhances the thermal conductivity of the hydrogel but also modulates its microstruc-ture,optimizing its moisture absorption-desorption characteristics.In this study,a series of carbon nanoparticle-doped hydro-gels were developed,and their moisture absorption-desorption properties were analyzed to evaluate their potential for passive cooling in solar cells. Methods To evaluate the moisture management performance of hydrogels,samples with five different mass fractions of carbon nanoparticles were synthesized and tested(S1-5).Moisture absorption tests were conducted in a constant temperature and humidity chamber(25℃),where changes in hydrogel mass were recorded over time.Desorption tests were then performed in a still air laboratory environment,where the doped hydrogels were applied as cooling layers on solar panels and illuminated by a solar simulator.A precision electronic balance continuously measured the hydrogel mass during evaporation,while thermo-couples monitored the back-surface temperature of the solar cells.In addition,an electrochemical workstation was used to moni-tor the current-voltage(Ⅰ-Ⅴ)characteristics of the solar cells.Data analysis and visualization were performed using Origin soft-ware to quantitatively evaluate the cooling performance of each hydrogel sample.This comprehensive evaluation aimed to deter-mine how carbon nanoparticle doping enhances the evaporative cooling efficiency of hydrogels for photovoltaic applications. Results and Discussion The results showed that S5 exhibited the highest moisture absorption capacity.Under standard illumi-nation conditions,the desorption capacity was significantly enhanced in hydrogel samples doped with carbon nanoparticles.Among them,S2 demonstrated the best desorption and cooling performance.To further explore the cooling performance,key performance parameters of the solar cells were tested.In real hydrogel applications,the open-circuit voltage increased by approximately 30 mV,the fill factor improved by 4.58％,and the energy conversion has increased by 0.41％. Conclusion This study develops and evaluates carbon nanoparticle-doped hydrogels for the passive cooling of solar cells.The hydrogel containing 20％carbon nanoparticles shows the highest water absorption capacity,while the sample with 5％carbon nanoparticles exhibits the most favorable desorption and cooling performance.The introduction of carbon nanoparticles signifi-cantly improves the hydrogel's moisture absorption-desorption efficiency and accelerates water evaporation,thereby improving the passive heat dissipation capacity of solar cells.

Abstract:Objective Cement production is known for its high energy consumption and significant environmental pollution.Reducing cement usage in construction industry is key to minimize pollution.Lithium slag(LS),a solid waste generated during the extrac-tion of lithium carbonate from spodumene ore through nitric acid pressure leaching,contains 96.9％of alumina and silicon oxide,displaying potential pozzolanic activity.LS can be used as a mineral admixture in cement-based materials to reduce cement consumption.However,the particle size of mineral admixtures affects their pozzolanic activity and the performance of blended cement.This paper studies the effects of LS particle sizes on the pozzolanic activity and the performance and mechani-cal properties of the blended cement. Methods After drying LS at(105±2)℃ for 24 h,LS powders with different particle sizes were prepared through ball milling for 20,40,60,80,100,and 120 min.The specific surface area of the resulting LS powders was measured,and four samples with distinct particle size distributions were selected for further experiments.These samples were named as LS1,LS2,LS3,and LS4 from smallest to largest particle size.Their particle size distribution and microstructure were analyzed using laser particle size analyzer and scanning electronic microscope(SEM).P·O 42.5R cement,LS1～LS4,and standard sand were used as the main materials.The water-binder mass ratio was 0.5,the mortar mass ratio was 1∶3,and the relative cement mass was 30％.LS with different particle sizes was blended to prepare standard mortar test blocks of 40 mm×40 mm×160 mm.The pure cement paste and LS1～LS4 composite pastes with 30％relative cement mass were named as A0,A1,A2,A3,and A4,respectively.The cement mortar and paste test blocks were cured with specified duration under conditions of(20±2)℃ and 90％relative humidity,and their compressive strength was measured at 3,7,28,56,and 90 d.The mix ratio of the cement paste was the same as that of the mortar,with the standard sand removed.Based on the mix ratio of cement paste,the effects of different LS particle sizes on the fluidity,setting time,and water requirement for normal consistency were assessed.Hardened cement paste specimens were prepared and cured for 28 and 90 d.The effects of LS on the hydration products and pore structure of the cement with different curing days were tested using X-ray diffraction(XRD),Fourier transform infrared spectrum(FTIR),and mercury intrusion porosimetry(MIP).The hydration heat release rate and hydration heat release of A0,A1～A4 pastes within 72 h were measured using hydration heat analyzer. Results and Discussion The results showed that as ball milling time increased,LS particle size gradually decreased,exhibiting a more spherical shape.Compared to A0,the water requirement for normal consistency increased by 1.5％for A1 and 3.5％for A4.Fluidity decreased by 16.9％for A1 and 44.6％for A4.The initial setting and final setting times for A1 decreased by 15.5％and 5.3％,respectively,and for A4,these values decreased by 27.4％and 14.3％.Hydration heat test results showed that the addition of LS reduced the heat release rate and cumulative heat release.However,with the decrease in LS particle size,both the heat release rate and the cumulative heat release increased,although the overall hydration reaction rate was lower than that of pure cement paste.The compressive strength of A1～A4 cement mortars was lower than that of A0 in the early stage of hydration(3,7 d).At 28 d,the compressive strength of A4 reached 122.6％,with a strength of 52.1 MPa,while other LS samples had lower strengths than A0.Beyond 56 d,the compressive strength of the mortars ranked from highest to lowest was A4,A3,A2,A1,andA0,indicating that smaller LS particle sizes promoted the long-term strength development of cement mor-tar.XRD analysis showed that the intensity of calcium hydroxide(CH)diffraction peak of A1～A4 was lower than that of A0 at 28 d,and decreased with smaller LS particle sizes.At 90 d of curing,the change in CH diffraction peak intensity was consistent with that observed at 28 d,but the decrease in CH peak intensity was more pronounced,This indicated that the active alumino-silicate in LS underwent a secondary hydration reaction with CH generated by cement hydration reaction,forming more calcium aluminosilicate gel.Also,the smaller the LS particle size,the more CH was consumed,resulting in a greater amount of hydrated calcium silicate gel,which promoted strength development.This trend was consistent with the compressive strength results of the mortar.FTIR and MIP analysis demonstrated that the addition of LS increased the content of calcium aluminosili-cate hydrate gel,further optimized the pore structure of the hardened cement paste,and increased the volume fraction of gel pores in the test blocks.These findings confirmed that smaller LS particle sizes effectively promoted the cement hydration reac-tion and improved the compressive strength of the mortar. Conclusion In this paper,the effects of nitric acid pressure leaching-extracted lithium slag powder with different particle sizes on its pozzolanic activity and the properties of the blended cement were studied.The study provides valuable insights into the use of LS in sustainable building materials.

Abstract:Significance Nanozymes are nanomaterials with enzymatic properties that can catalyze substrate transformation under physi-ological conditions and exhibit reaction kinetics similar to natural enzymes.However,their widespread application is hindered by slow catalytic kinetics and low efficiency.Moreover,the unclear catalytic active sites constrain our understanding of their catalytic mechanism.As a result,constructing multifunctional nanozymes with well-defined active sites and high catalytic per-formance remains a significant challenge.Single-atom catalysts(SACs)mimic the catalytic center structure and activity of natu-ral metalloproteases and are considered potential substitutes for natural metalloenzymes.The metal active sites of SACs are uni-form,and their coordination environment is controllable,enabling the maximum utilization of metal atoms.This provides an ideal model for studying the structure-performance relationship.Cobalt-based single-atom catalysts(Co-SACs)exhibit out-standing performance in chemical and biological reactions.Exploring their catalytic performance across various reactions and evaluating their potential for large-scale industrialization is crucial for the advancement of related fields.Such efforts uncover the application value of nanozymes and provide innovative solutions for real-world production challenges. Progress The oxidase-like activities of Co-SACs are classified into multiple functional types based on their catalytic substrates,primarily including aromatic amine oxidase-like activity,lactate oxidase-like activity,siloxane oxidase-like activity,reduced nicotinamide adenine dinucleotide(NADH)oxidase-like activity,and laccase-like activity.Further investigations into their modulation strategies reveal that performance regulation can be achieved through precise control of coordination numbers,direc-tional heteroatom doping,construction of cobalt-transition metal synergistic effects,and optimization of metal-support interfa-cial interactions.Owing to their well-defined atomic-level structures and tunable coordination microenvironments,Co-SACs demonstrate remarkable advantages in advanced applications such as biosensing,tumor therapy,and organic synthesis. Conclusions and Prospects Despite great progress,the future development of Co-SACs faces both challenges and opportuni-ties.Future research should focus on optimizing cobalt active site loading and stability,as current limitations in these aspects restrict catalytic performance and may lead to particle aggregation.To address this,mild non-calcination strategies and function-alized support should be explored to enhance loading efficiency and stability,thereby facilitating large-scale synthesis.Building upon prior experience in precursor selection and condition optimization,engineering approaches for industrial-scale production and green synthesis methods can be developed.Additionally,it is crucial to improve catalytic selectivity and study the reaction mechanism.Future research should combine theoretical and experimental approaches to analyze factors influencing selectivity,ultimately establishing quantitative structure-activity models for precise catalyst design.

Abstract:Significance The transport mechanisms of lithium ions in solid polymer electrolytes(SPEs)are critical for determining the per-formance of next-generation batteries.The mechanisms encompass multiple intricate processes,including ion coordination,intra-and inter-chainhopping,and segmental motions of polymer chains.These processes collectively influence essential param-eters such as ionic conductivity and lithium-ion mobility,which are pivotal for the development of high-performance SPEs.How-ever,a fundamental understanding of these mechanisms remains a key challenge,and the rational design of advanced SPEs is required.This paper comprehensively reviews the research progress in this field,covering theoretical models,experimental spectroscopic characterization,and computational simulations,highlighting future research directions and opportunities. Progress Historically,the investigation of ion transport in SPEs has employed empirical and semi-empirical models to describe the temperature-and composition-dependent ionic conductivity.Among these,the Arrhenius model has been widely employed to characterize thermally activated ion transport,particularly in crystalline or glassy electrolytes.However,it often fails to cap-ture the complex behavior of polymer systems,where segmental motion dominates.The Vogel-Tammann-Fulcher(VTF)model addresses this limitation by incorporating free volume and glass transition temperature,making it more appropriate for amor-phous polymers.The William-Landel-Ferry(WLF)equation further refines this approach by providing a more nuanced descrip-tion of temperature-dependent polymer dynamics.However,these models have inherent limitations and need experimental data to achieve a more precise prediction of ion transport behavior in SPEs.Recent advancements in spectroscopic techniques have revolutionized our understanding of the dynamic processes underlying lithium ion transport in SPEs.Infrared(IR)spectros-copy,for instance,has been instrumental in probing the coordination environment of lithium ions and their interactions with polymer chains.Terahertz(THz)spectroscopy offers a distinctive perspective on the low-frequency dynamics of ions and poly-mer segments,revealing details about ion hopping and collective motion.These techniques,often combined with time-resolved measurements,have enabled the direct observation of real-time ion coordination states and transport processes.Such experimen-tal breakthroughs are invaluable for validating theoretical models and guiding the design of novel SPE materials.Molecular dynamics(MD)simulations have emerged as an essential tool for studying ion transport in SPEs at the atomic and molecular lev-els.Classical MD simulations,utilizing empirical force fields,are widely used due to their balance between computational effi-ciency and accuracy.These simulations have significantly advanced our understanding of ion coordination,polymer segmental motion,and ion hopping.However,the simulation accuracy is often constrained by the quality of the force fields,particularly for complex polymer systems.Recent methodological advancements have promoted the development of coarse-grained MD tech-niques,where computational costs are substantially reduced by simplifying the representation of polymer chains while preserving critical physical features.Additionally,machine learning-based MD simulations have emerged as an advantageous alternative,potentially achieving quantum-level accuracy at a significantly lower computational cost.These advanced simulation methods are particularly promising for studying complex interfacial phenomena in composite electrolytes and electrode-electrolyte sys-tems.Despite significant progress,several challenges persist.A prominent challenge lies in the development of accurate and transferable force fields for MD simulations,especially for multi-component systems and interfaces.Another challenge is the integration of experimental and computational approaches to provide a more holistic understanding of ion transport mechanisms.For example,combining spectroscopic data with MD simulations can bridge the gap between macroscopic properties and micro-scopic processes.Additionally,the development of new electrolyte materials,such as hybrid organic-inorganic electrolytes and gel-based systems,presents new opportunities and challenges for both experimental and computational studies.Future research should also focus on translating these insights into practical battery systems,with particular attention to electrode compatibility,cycling stability,and safety. Conclusions and Prospects Understanding the transport mechanisms of lithium ions in SPEs is a complex scientific challenge that demands integrated theoretical,experimental,and computational studies.Although significant progress has been made,many challenges persist,particularly in relation to complex materials and interfaces.Advancements in spectroscopic tech-niques,MD simulations,and machine learning methods are promising in addressing these issues.A deeper understanding of ion transport in SPEs could pave the way for the development of next-generation batteries with improved performance,safety,and sustainability.This review highlights the importance of interdisciplinary collaboration and innovative methodologies in advancing this critical research field.

Abstract:Significance To address the key"bottleneck"problem hindering the development of China's semiconductor industry,namely the efficient and cost-effective production of electronic specialty gases(ESG),studies have been conducted on the adsorption and separation of fluorohydrocarbons using porous materials,aiming to achieve the purification of key fluorohydrocarbon sys-tems.Customized porous adsorbents have been developed to address the low efficiency and excessive energy consumption associ-ated with traditional distillation methods.Through material design and process optimization,an efficient separation system is established,facilitating large-scale domestic production of ESG for semiconductor manufacturing in China. Progress Distillation,a traditional purification method,exhibits limitations in separating impurities from fluorohydrocarbons with similar boiling points,making it extremely difficult to achieve the ultra-high purity(5N,exceeding 99.999％)demanded by ESG standards.Additionally,the process faces challenges such as high energy consumption and substantial investment costs,highlighting the urgent need to develop alternative separation and purification technologies,particularly porous material-based methods.Studies have shown that porous materials are exceptional in two critical aspects:selective gas separation and high-capacity single-component adsorption.Their tunable pore structures and customizable surface chemistries enable precise molecular recognition,allowing efficient isolation of target compounds from complex gas mixtures with remarkable selectivity.In addition to separation performance,these materials also exhibit outstanding adsorption capacities for individual components,making them versatile for applications ranging from gas purification to storage.Recent studies have further evaluated their long-term stability and regeneration potential,with studies confirming that many porous materials maintain adsorption efficiency over multiple cycles while preserving structural integrity.This robust combination of high selectivity,large adsorption capacity,and cycling stability positions porous materials as ideal candidates for sustainable industrial processes,including carbon capture,hydrogen storage,and high-value chemical recovery.This review summarizes recent advancements in the porous material-based adsorption and separation of key fluorohydrocarbons,including CF4,C2F6,and C3F8,focusing on activated carbon,carbon molecular sieves,and metal-organic frameworks(MOFs). Conclusions and Prospects Porous material-based adsorption and separation technology is well-suited for the purification of fluorohydrocarbon ESG due to its operational simplicity,mild processing conditions,and high efficiency in removing trace impu-rities.This technology not only meets the current purity requirements for ESG but also exhibits strong potential to achieve even higher purity levels.Research has shown that porous materials can achieve favorable outcomes in two key parameters:single-component adsorption and gas mixture selectivity.In addition,some studies have confirmed the excellent stability and recy-clability of these materials.Future research should focus on the computational-guided rational design of porous materials to opti-mize their adsorption capacity and selectivity.Also,experimental validations under actual industrial operating conditions should be conducted to ensure that these adsorptive gas separation technologies are scalable and economically feasible.Special atten-tion should be paid to their long-term stability and reusability under diverse operating conditions.With rising industrial demands,enhancing regeneration efficiency and maximizing the operational durability of porous adsorbents will emerge as criti-cal research priorities.To promote sustainable implementation,material development strategies should also incorporate in-depth analyses of the environmental impact and economic viability.Consequently,subsequent research endeavors should address three key areas:material performance,technological reliability,and sustainability.Such a multidimensional strategy is crucial for ensuring the long-term stability,durability,and efficiency of porous material-based purification technologies in industrial applications.Ultimately,these technologies are poised to play a pivotal role in the industrial production of high-purity fluorohy-drocarbons,driving innovative development across industries.

Abstract:Objective Color images are typically processed using the Bayer pattern in the color filter array(CFA)during image acquisition.However,this approach often generates a band of artifact pixels around image edges,causing colors deviation from the actual objects.To address this issue,this paper proposes a method for identifying and removing edge artifact pixels in color images,thereby improving the accuracy of color representation for real-world objects and laying the foundation for future international standards. Methods A simulation program for generating color images was constructed in Matlab software.Opaque black simulated par-ticles were used as the research object to mimic the conversion process from raw(RAW)to RGB(red,green and blue channels)format images under the Bayer filter within the CFA.A color image acquisition setup was established to capture images of a dot calibration board,and the actual size and color of the black dots were calibrated to investigate the formation mechanism of edge artifacts in color images.A combined approach of simulations and experiments was adopted to examine the impact of 6 demosaic-ing interpolation algorithms and lens chromatic aberration on the number of artifact pixels in color images.To validate this method,red and blue polystyrene particles and yellow and white paracetamol-caffeine-artificial cow-bezoar-chlorphenamine maleate granules were used as application subjects.Color images of these particles were captured,and changes in color moments and chromaticity coordinates before and after artifact removal were analyzed.It demonstrated the method's applicability and universality across different particle types. Results and Discussion In simulated color images,the 6 demosaicing interpolation algorithms generated ftom 2 to 3 edge artifact pixels.The number of edge artifact pixels in the captured images of black dots exceeded 3.These 6 interpolation algorithms exhibited different degrees of influence on the mean,maximum,and modal values of color differences in the converted RGB color images.When 5 edge artifact pixels were removed,the standard deviations of the R,G,and B channel values in the black dot images all fell below 0.01,approaching background noise levels.The removal of artifact pixels effectively removed the arti-facts,and color fluctuations were minimized.Upon the removal of 5 edge artifact pixels,the first-order moments in the color moments of the particle images for both polystyrene and paracetamol-caffeine-artificial cow-bezoar-chlorphenamine maleate granules increased.However,the second and third-order moments decreased.The distribution area of particle pixels in the chromaticity coordinate diagrams was significantly reduced,and the clustering of coordinate points was enhanced.These results accurately reflected the true colors of the particles. Conclusion The edge artifact pixel identification and removal methods effectively reduce statistical color differences in color images.The overall luminance of particle images is closer to their true values,the color fluctuation is decreased,and the bal-ance of light and dark tones is achieved.The dual goals of color fidelity and morphological fidelity are achieved.

Abstract:Objective To improve the separation efficiency of carbonate-containing refractory iron ore and achieve efficient utilization of complex and refractory iron ore resources,the dispersion performance and mechanism of carbonate-containing mixed magnetic concentrate slurry treated with different dispersants are studied,providing a basis for the application of dispersants in refractory ore separation. Methods The mixed magnetic concentrate from the Dong'anshan Sintering Plant was used as the research object,and a disper-sion experimental device was independently designed.Based on mineral sample analysis,the dispersion effects of small-molecule organic dispersants(citric acid,malic acid,butane tetracarboxylic acid),a large-molecule organic dispersant(sodium carboxymethyl cellulose),and inorganic dispersants(sodium silicate,sodium hexametaphosphate)on the slurry were investigated.The effects of different dispersants on the slurry's dispersibility,turbidity,particle size distribution,and aggrega-tion state were studied,revealing the dispersion mechanism of these dispersants. Results and Discussion The total iron(TFe)grade of the mixed magnetic concentrate sample was 42.97％.The yield of par-ticles with a particle size smaller than 48 μm in the ore sample was about 84％,of which particles smaller than 23 μm were about 45％.The particle size of Fe was mainly less than 37 μm,with a metal distribution rate of over 80％.Fine particles were prone to mutual adsorption and agglomeration,adhering to the coarse particle surface of useful iron minerals and gangue miner-als,making ore separation difficult.The addition of dispersants enhanced the dispersibility of the mixed magnetic concentrate slurry.The dispersion degree of the slurry treated with the polymer organic dispersant CMC-Na and two inorganic dispersants,sodium hexametaphosphate and sodium silicate,was less than 35％,while the dispersion degree for the three small-molecule dispersants,malic acid,citric acid,and butanetetracarboxylic acid,was greater than 46％,demonstrating stronger dispersion effects.These dispersants also exhibited advantages such as good water solubility,high efficiency,non-toxicity,low cost,and wide availability.When the mass concentration of citric acid,malic acid,and butanetetracarboxylic acid was 440 mg/L,the slurry turbidity reached its maximum values of 1 850,1 900,and 2 000 NTU,respectively.Under the influence of these three small-molecule organic dispersants,a large number of fine particles were restored from an agglomerated state to a single particle state,enabling better dispersion in water and an increase in slurry turbidity.The D50 values of the slurry particles treated with citric acid,malic acid,and butanetetracarboxylic acid were 21.98,20.97,and 19.67 μm,respectively,while the D90 values were 64.73,62.69,and 61.65 μm,respectively.All three dispersants reduced the apparent size of the slurry particles. Conclusion After adding the three small-molecule organic dispersants-citric acid,malic acid,and butanetetracarboxylic acid-to the slurry,a combined effect of electrostatic repulsion,hydration repulsion,and steric hindrance was induced.This syner-gistic action broke the agglomeration and surface adhesion among fine particles,causing them to transition from an aggregated state to a monodispersed state.As a result,the dispersion and turbidity of the slurry increased while the particle size decreased.

Abstract:Objective To address the issues of limited accessible surface area and high mass transfer resistance in commercial porous car-bon,it is essential to develop new methods for preparing mesoporous carbon.This study proposes a novel preparation method for mesoporous carbon and evaluates its potential as an electrode material for supercapacitors,providing valuable insights into the mechanisms of mesopore formation. Methods The resulting mesoporous carbon was characterized using scanning electron microscopy(SEM),transmission electron microscopy(TEM),Raman spectroscopy,X-ray photoelectron spectroscopy(XPS),and N2 adsorption/desorption to determine its microstructure features and evaluate its application potential as a supercapacitor electrode.Its electrochemical performance was evaluated.Additionally,the preparation process was examined,and the reaction mechanism was proposed and discussed. Results and Discussion Pore structure analysis showed that the obtained mesoporous carbon had a specific surface area of 752 m2·g-1,a total pore volume of 1.22 cm3·g-1,and a pore width of 5.3 nm,making it suitable for high-performance superca-pacitors with aqueous electrolytes.Raman spectroscopy revealed a 2D peak at 2 675 cm-1,with ID/IG and I2D/IG ratios of 0.7 and 0.8,respectively,confirming the presence of few-layer graphene nanosheets with a turbostratic structure.Additionally,regions of local order were observed via high-resolution TEM(HRTEM),indicating a high degree of graphitization.When applied in supercapacitors,the mesoporous carbon had a specific capacitance of 113 F·g-1 at a current density of 50 A·g-1,and maintained an excellent capacitance retention of 76％when the current density increased from 1 A·g-1 to 50·A g-1. Conclusion This paper proposes a novel molten salt-assisted magnesiothermic reduction method for preparing mesoporous car-bon,with sodium carbonate serving as the carbon source.During the synthesis process,sodium carbonate exhibits a catalytic activation effect at a relatively low temperature(800 ℃),enhancing the degree of graphitization of the product.Additionally,the chloride molten salts facilitate the free movement and assembly of the resulting product.The obtained mesoporous carbon exhibits a high specific surface area and pore volume,with a uniform pore size of 5.3 nm,making it suitable for aqueous electro-lyte energy storage.It also features a low defect density.When applied as an electrode material for supercapacitors,the mesopo-rous carbon demonstrates excellent electrochemical performance at high current densities,outperforming the commercial supercapacitor-grade activated carbon YP-80F.The product's high specific surface area and pore volume,suitable pore width,local order,and graphene structure enable rapid charge/discharge behaviour in aqueous electrolytes.Therefore,the prepared mesoporous carbon shows potential as a supercapacitor electrode,exhibiting excellent specific capacitance and capacitance retention performance.

Abstract:Significance Rare earth(RE)-based catalysts have garnered extensive attention in NH3-selective catalytic reduction(SCR)reactions due to their strong redox capabilities,acidity,and exceptional thermal and chemical stability,particularly in RE oxides.Numerous RE-based NH3-SCR catalysts have been developed for the ability of RE elements to substitute for other ele-ments.The versatility allows them to function as primary catalyst components,secondary components,and co-catalysts.Under-standing the mechanisms of RE elements across various catalyst types,such as metal oxide catalysts and zeolite molecular sieve catalysts,is crucial for developing novel high-performance NH3-SCR catalysts. Progress This paper reviews recent advancements over the past five years in RE-based NH3-SCR catalysts,focusing on CeO2-based catalysts,RE-modified MnOx-based catalysts,and Cu-exchanged zeolite catalysts.Additionally,natural mineral cata-lysts have garnered increasing attention due to their potential economic value,and the latest research trends in rare earth tailings(RET)catalysts are also reviewed.By analyzing the active sites,reaction pathways,and rate-determining steps of RE-based catalysts,the role of RE elements in different catalysts is summarized as follows:1)For metal oxide-based and RET catalysts,the enhancement of their activity by RE elements is primarily attributed to the redox properties and acid-base properties of RE compounds and the synergistic effects between RE elements and transition metals.Specifically,electronic interactions between transition metals(Mn,Mo,Ti,etc.)and RE elements(Ce,Sm,Y,etc.)form structural units such as M-O-RE and Ce3+-O-Ce3+,which regulate the surface acidity and redox capacity of the catalysts,promoting both the acid and redox cycles.2)For Cu-based zeolite catalysts,the introduction of RE ions increases the bond energy of Al-O in the zeolite framework,stabilizing the framework and improving hydrothermal stability.It also regulates the distribution of Cu active sites on the zeolite framework,promoting the formation of more active and hydrothermally stable Cu sites.3)The introduction of RE elements enhances the catalyst's tolerance to SO2.RE sites preferentially adsorb SO2,inhibiting sulfate deposition at active sites and preventing their deactivation.Additionally,the formation of an appropriate amount of sulfate on RE sites provides additional acidic sites,further enhancing the catalyst's activity. Conclusions and Prospects Future research can be explored in the following two directions.First,catalyst design should fully consider the complex conditions in actual denitrification processes,including operating temperature,atmosphere,and flue gas/exhaust composition.For example,diesel engine exhaust has high temperatures(～900 ℃)and contains complex hydrocarbons,the cold start emission of vehicles has low temperatures,and the composition of flue gas from different industrial sources,such as power plants and cement plants,varies.Customizing the composition and structure of denitrification catalysts to suit different working conditions will ensure that the catalysts exhibit good tunability and adaptability in various reaction environments,achiev-ing efficient and stable denitrification performance.Second,there is an urgent need to develop and apply new characterization techniques to more comprehensively analyze the structure-performance relationship of catalysts.Such techniques can be used to,for instance,quantify electron transfer between RE and transition metals or capture the potential involvement of 4f electrons distinct to RE during the NH3-SCR reaction process.This will help reveal the specific mechanisms of RE elements in the cata-lytic process,providing strong theoretical support for the precise design and performance optimization of catalyst structures.Through continuous efforts in these two directions,RE-based NH3-SCR catalysts are expected to demonstrate superior perfor-mance and broader application prospects in actual denitrification applications.

Abstract:Objective Efficient removal of solid particulate matter from exhaust gases is crucial for ensuring clean production processes in the energy industry.This study investigates a granular bed-cyclone coupled separator system,which enhances separation perfor-mance by integrating centrifugal separation with granular bed filtration.The built-in granular bed effectively captures and filters fine particles(＜5 μm),which are difficult to remove using centrifugal force alone.However,these particles tend to clog over time.To ensure long-term stable operation,the granular bed must be regenerated rapidly and effectively to remove the trapped particles.Currently,spouted bed regeneration technology is employed,but issues such as captured particle attrition and second-ary pollution from regenerated gas still exist,hindering its industrial application.To address this,riser-spouted bed regenera-tion technology is adopted to stabilize the pressure drop in the coupled separation system.Nevertheless,this method can still cause secondary emissions of fine particles,resulting in additional environmental concerns. Methods This paper analyzed the effects of optimization techniques,such as a newly designed screening regenerator and tail gas recirculation,on the performance of a granular bed-cyclone coupled separator system.Large-scale cold-model experiments were conducted to investigate the impact of inlet gas flow rate and dust concentration on separation performance under various exhaust gas recirculation ratios.The research focused on key performance parameters,including pressure drop,overall collection effi-ciency,outlet particle size distribution,and grade efficiency.A vibrating regenerator was designed and evaluated based on the coupled separation device.Its separation characteristics,including regeneration efficiency and pressure drop performance,in the micro-airflow vibrating regenerator were examined through experiments and compared with those of the conventional spouted regeneration methods.Additionally,the effects of screening regeneration on the overall performance of the coupled separator were further explored. Results and Discussion The introduction of regenerated exhaust gas significantly enhanced the separation efficiency of the coupled separator,with collection efficiency exceeding 99.2％across all operating conditions.The median particle diameter of dust in the outlet gas stream decreased from 1.67 μm to 0.82～1.04 μm,and the grade efficiency for dust particles smaller than 3 μm was notably improved.At an inlet dust concentration of 14.99 g/m3 and an exhaust gas recirculation ratio of 25％,the coupled separator achieved relatively high collection efficiency.Additionally,fine particles in the recirculated exhaust gas were primarily distributed within the 0.323～1.047 μm range,playing a crucial role in filter cake formation.Among the separated particles,92％of dust particles larger than 10 μm were captured by the cyclone shell,while the particle size distribution cap-tured by the granular bed varied with the recirculation ratio,primarily ranging from 0.409 to 10.954 μm.The optimal operating conditions for the micro-airflow vibrating regenerator were as follows:Ws=0.69 kg/s,ui=0-0.035 m/s,ρin=7.5～22.5 kg/m3.The experimental results showed that the maximum operating pressure drop of the vibrating regenerator was 80 Pa,much lower than that of the riser-spouted regenerator under similar circulation volume(3 kPa).Moreover,the efficiency of the vibrating regen-erator remained stable at 85％to 95％.Additionally,due to the low gas velocity of the vibrating regenerator,no significant frag-mentation of the captured particles occurred during the separation process.Based on the dust particles collection behaviour in the novel regenerator,two key mechanisms were identified:entrainment and screening.In the free-settling space,gas-solid phase countercurrent contact separation was achieved through the entrainment mechanism,while the screening mechanism func-tioned via interception on the sieve surface.When the regenerative gas velocity was below 0.02 m/s,the screen separation mechanism dominated.Larger dust particles fell into the dust collection tank due to inertial and gravitational forces,contribut-ing 50％～80％to regeneration efficiency.When the regenerative gas velocity exceeded 0.02 m/s,the gas flow entrainment effect intensified,and the contribution rate from this mechanism could reach up to 70.8％.Under the micro-airflow vibrating regenera-tion mode,the separation efficiency of the coupled separator ranged from 89.9％to 99.6％,and the pressure drop remained rela-tively stable and nearly unaffected by the changes in regeneration gas velocity.The centrifugal separation performed effectively for dust particles larger than 10 μm,with a separation contribution rate of approximately 90％.The built-in granular bed effec-tively trapped dust particles within a range of 0.32～10.95 μm. Conclusion The optimization of the regeneration system,achieved through precise control of key regeneration mechanisms and structural improvements,significantly enhances the particulate matter capture efficiency of the coupled separator.This optimiza-tion enables effective interception and separation of particles across varying sizes while maintaining stable processing efficiency under complex operating conditions.It thus provides solid technical support and practical validation for advancing the technol-ogy from laboratory research to industrial application,establishing a strong foundation for subsequent large-scale engineering implementation.

Abstract:Objective This study aims to address the poor compatibility between oil-absorbing resin and oil well cement,which leads to a reduction in the strength of cement stone,and to achieve oil-triggered self-healing of micro-cracks in the cement sheath,thereby ensuring the sealing integrity of the cement sheath in oil and gas wells.In this study,microcapsules with oil-swelling and micro-crack self-healing functions are prepared.The microcapsules are fabricated via a chemical precipitation method using oil-absorbing resin as the core material and reactive silica as the shell material. Methods Scanning electron microscopy(SEM)imaging,thermogravimetric analysis(TG),Fourier-transform infrared(FTIR)spectroscopy,and energy-dispersive spectroscopy(EDS)mapping were employed to test and characterize the oil-absorbing resin and the microcapsule.The oil-swelling and micro-crack self-healing performance of cement samples incorporating the oil-absorbing resin or microcapsule was evaluated by investigating their compressive strength,recovery rate of compressive strength,and permeability.Furthermore,SEM imaging and EDS mapping were conducted on thin sections extracted from crack surfaces of the cement samples to investigate the micro-crack self-healing mechanism in cement systems containing oil-absorbing resin or microcapsule. Results and Discussion The median particle sizes(D50)of the oil-absorbing resin and the microcapsule were 5.601 pm and 6.590 pm,respectively.Within the temperature range of 0-213 ℃,both the oil-absorbing resin and the microcapsule exhib-ited almost no mass loss,demonstrating good thermal stability that met the requirements for cementing operations.Within the temperature range of 214-304 ℃,the mass loss rates for the oil-absorbing resin and the microcapsule were 95.45％and 35.84％,respectively,indicating superior thermal stability of the microcapsule.A vibrational absorption peak for Si-OH was observed at a wavenumber of 941 cm-1,indicating that the oil-absorbing resin was encapsulated within the silica shell.The microcapsule possessed a large specific surface area,which helped improve their dispersion stability and interfacial bonding per-formance within the cement matrix.After 6 hours of oil absorption,the volume expansion rates of the oil-absorbing resin and the microcapsule were 100％and 10％,respectively,demonstrating the integrity and effectiveness of the silica shell encapsulation.The compressive strength of cement sample A1,incorporating microcapsule,reached its maximum value at a curing age of 7 days,indicating an optimal microcapsule dosage of 1％.After a self-healing curing age of 28 days,sample A1 exhibited a com-pressive strength of(29.06±1.61)MPa and a compressive strength recovery rate of 79.05％.Although both the oil-absorbing resin and microcapsule improved the compressive strength recovery capability of the cement stone,the incorporation of oil-absorbing resin led to a decrease in the overall compressive strength.Therefore,microcapsule was more suitable for the self-healing of micro-cracks in cement stone.After a self-healing curing age of 28 days,sample A,showed a permeability of 0.563× 10-3 μm2,representing a reduction of 39.36％,indicating a significant decrease in the permeability of the cement stone. Conclusion The silica shell of the microcapsule possesses high reactivity,enabling it to participate in the cement hydration pro-cess and provide nucleation sites,thereby enhancing the compressive strength of the cement stone after damage and addressing the issue of strength reduction caused by the incorporation of oil-absorbing resin.When a crack forms in cement containing microcapsules,the silica shell is fractured by the stress at the crack tip,exposing the internal oil-absorbing resin.Upon contact with oil,the oil-absorbing resin swells and becomes adsorbed and aggregated among the hydration products and pores,making the microstructure of the cement stone more uniform and dense,thereby effectively promoting the self-healing process of the cement stone.