Polystyrene(PS)waste was depolymerized using a low-temperature pyrolysis treatment(LTPT)to increase its caking index.The mechanism of caking index modification was revealed by using Fourier transform infrared spectros...Polystyrene(PS)waste was depolymerized using a low-temperature pyrolysis treatment(LTPT)to increase its caking index.The mechanism of caking index modification was revealed by using Fourier transform infrared spectroscopy,thermogravimetric(TG)analysis,pyrolysis-gas chromatography with mass spectrometric detection,and solid-state^(13)C nuclear magnetic resonance spectroscopy.The crucible coal-blending coking tests were carried out using an industrial coal mixture and the treated-PS with the highest caking index(PS300)or raw PS.Some properties of the resultant cokes were also analyzed.It was demonstrated that the caking index of PS dramatically increased by LTPT;however,exceeding 300℃ did not yield any benefit.The caking index increased due to the formation of the caking components,whose molecules are medium in size,caused by LTPT.Additionally,the coke reactivity index of the coke obtained from the mixture containing PS300 decreased by 5.1%relative to that of the coke made from the mixture with PS and the coke strength after reaction index of the former increased by 7.3% compared with that of the latter,suggesting that the ratio of depolymerized PS used for coal-blending coking could increase relative to that of PS.展开更多
As one of the most promising new energy sources,hydrogen energy is expected to usher in a full-fledged“hydrogen economy”in the 21st century.Compared with traditional high-pressure gaseous and cryogenic liquid hydrog...As one of the most promising new energy sources,hydrogen energy is expected to usher in a full-fledged“hydrogen economy”in the 21st century.Compared with traditional high-pressure gaseous and cryogenic liquid hydrogen storage methods,solid-state chemical hydrogen storage shows significant advantages in safety,high efficiency,and cost-effectiveness.Magnesium-based lightweight hydrogen storage materials have attracted widespread attention due to their high gravimetric hydrogen storage density(7.6%)and favorable reversibility.However,their sluggish reaction kinetics and stringent operating conditions(with H2 release temperatures exceeding 350°C and H2 absorption pressures above 4 MPa)pose major challenges for practical applications.Domestic and international researchers have conducted in-depth studies to address these issues,achieving substantial progress in the modification of magnesium-based hydrogen storage alloys.This paper systematically elaborates on major modification techniques such as alloying,nanostructuring,and catalytic material doping,providing a comprehensive analysis of the strengths and limitations of each approach.Furthermore,it offers prospects for the future development of magnesium-based hydrogen storage materials by integrating current theoretical and experimental research findings.展开更多
Biomass-derived carbon materials are favored for their abundance and sustainability,and ease of preparation and modification.By surface activation and modification they can have a good electrical conductivity,excellen...Biomass-derived carbon materials are favored for their abundance and sustainability,and ease of preparation and modification.By surface activation and modification they can have a good electrical conductivity,excellent catalytic activity,a remarkable adsorption capacity,and different interfacial physicochemical functionalities.Surface-modified biochars have found wide applications in energy storage,environmental remediation,and catalysis.However,achieving precise and controllable modification of their active sites remains a challenge.Recent advances and future prospects for controlling their surface morphology,defect engineering,and surface coating strategies,with particular attention to their means of fabrication,are reviewed.展开更多
Post-translational modifications(PTMs)regulate the occurrence and development of cancer,and lactylation modification is a new form of PTMs.Recent studies have found that lactic acid modification can regulate the immun...Post-translational modifications(PTMs)regulate the occurrence and development of cancer,and lactylation modification is a new form of PTMs.Recent studies have found that lactic acid modification can regulate the immune tolerance of cancer cells.The classical theory holds that prostate apoptosis response-4(PAR-4)is a tumor suppressor protein.However,our recent research has found that PAR-4 has a biological function of promoting cancer in hepatocellular carcinoma(HCC),and our analysis shows that PAR-4 can be modified of lactic acid.These research evidences suggest that PAR-4 lactylation modification may drive immune tolerance in HCC.Therefore,inhibiting PAR-4 lactylation modification is very likely to increase the sensitivity of HCC to immunotherapy.展开更多
Bentonite is a necessary binder in producing pellets.Its excessive use reduces the iron grade of pellets and increases production costs.Minimizing bentonite dosage is essential for producing high-quality iron ore pell...Bentonite is a necessary binder in producing pellets.Its excessive use reduces the iron grade of pellets and increases production costs.Minimizing bentonite dosage is essential for producing high-quality iron ore pellets.Addressing the gap in the application of organically-intercalated modified bentonite in the pelletizing field,this study introduces an innovative modification process for bentonite that employs the synergistic effect of mechanical force and dimethyl sulfoxide to enhance the intercalation of organic compounds within bentonite,thus significantly enhancing its binding performance.The colloid value and swell capacity of modified bentonite(98.5 m L/3g and 55.0 m L/g)were much higher than the original bentonite(90.5 m L/3g and 17.5 m L/g).With the decrease of bentonite dosage from1.5wt%to 1.0wt%,the drop number of green pellets from a height of 0.5 m and the compressive strengths of roasted pellets using the modified bentonite(6.0 times and 2916 N per pellet)were significantly higher than those of the original bentonite(4.0 times and 2739 N per pellet).This study provides a comprehensive analysis of the intercalation modification mechanism of bentonite,offering crucial technical insights for the development of high-performance modified bentonite as iron ore pellet binders.展开更多
The implementation of multifunctional application scenarios for mobile terminal devices has increased the energy density requirements of batteries.Increasing the charging voltage can rapidly increase the specific capa...The implementation of multifunctional application scenarios for mobile terminal devices has increased the energy density requirements of batteries.Increasing the charging voltage can rapidly increase the specific capacity of layered transition metal oxides;however,it also exacerbates the release of lattice oxygen and the contraction of the unit cell.Ternary materials are designed in a secondary particle state to meet the requirements of power battery applications.Therefore,to create ternary materials that can operate under ultrahigh voltages,attention should be given to both surface modification and particle integrity maintenance.By utilizing elemental selenium(Se)with a low melting point,easy sublimation,and multiple variable valence states,deep grain boundary modification was implemented inside the particles.The performance of the cathode material was evaluated through pouch cells,and the improvement mechanism was explored through molecular dynamics simulation calculations.Under the protection of a three-dimensional Se-rich modified layer,LiNi_(1/3)Co_(1/3)Mn_(1/3)O_(2)achieved stable operation at ultrahigh voltages(4.6 V vs.Li/Li^(+));a sacrificial protection mechanism based on the chronic decomposition of the Se-rich layer was proposed to explain the efficacy of Se modification in stabilizing ternary materials.This deep grain boundary modification based on elemental Se provides a new solution for the ultrahigh-voltage operation of transition metal oxides and provides a scientific basis and technical support for solving the interface contact problem of all-solid-state batteries.展开更多
Perovskite solar cells have achieved remarkable progress in photovoltaic efficiency.However,interfacial defects at the buried and upper interfaces of perovskite layer remain a critical challenge,leading to charge reco...Perovskite solar cells have achieved remarkable progress in photovoltaic efficiency.However,interfacial defects at the buried and upper interfaces of perovskite layer remain a critical challenge,leading to charge recombination,ion migration,and iodine oxidation.To address this,we propose a novel all-in-one modification strategy employing ammonia borane(BNH6)as a multifunctional complex.By incorporating BNH6 at both buried and upper interfaces simultaneously,we achieve dualinterfacial defect passivation and iodide oxidation suppression through three key mechanisms:(1)hydrolysis-induced interaction with SnO_(2),(2)coordination with Pb^(2+),and(3)inhibition of I−oxidation.This approach significantly enhances device performance,yielding a champion power conversion efficiency(PCE)of 26.43%(certified 25.98%).Furthermore,the unencapsulated device demonstrates prominent enhanced operation stability,maintaining 90%of its initial PCE after 500 h under continuous illumination.Notably,our strategy eliminates the need for separate interface treatments,streamlining fabrication and offering a scalable route toward high-performance perovskite photovoltaics.展开更多
Two-step-processed(TSP)inverted p-i-n perovskite solar cells(PSCs)have demonstrated significant promise in tandem applications.However,the power conversion efficiency(PCE)of TSP p-i-n PSCs rarely exceeds 24%.Here,we d...Two-step-processed(TSP)inverted p-i-n perovskite solar cells(PSCs)have demonstrated significant promise in tandem applications.However,the power conversion efficiency(PCE)of TSP p-i-n PSCs rarely exceeds 24%.Here,we demonstrate that TSP perovskite films exhibit a vertically gradient distribution of residual PbI_(2)clusters,which form Schottky heterojunctions with the perovskite,leading to substantial interfacial energy-level mismatches within NiO_(x)-based TSP p-i-n PSCs.These limitations were effectively addressed via a vertical interfacial engineering enabled by dual-interface modification incorporating tin trifluoromethanesulfonate(Sn(OTF)_(2))and 4-Fluorophenylethylamine chloride(F-PEA)at the NiO_(x)/perovskite and perovskite/C60 interfaces,respectively.The functional Sn(OTF)_(2)not only enhances the conductivity of NiO_(x)films but also suppresses ion migration,while inducing the formation of a Pb-Sn mixed perovskite interlayer that precisely regulates the energy level at the NiO_(x)/perovskite interface.Complementally,F-PEA post-treatment effectively converts surface residual PbI_(2)clusters into a 2D perovskite capping layer,which simultaneously passivates surface defects and enhances energy-level alignment at the perovskite/C60 interface.Consequently,the optimized NiO_(x)-based TSP p-i-n PSCs achieve a notable PCE of 25.6%with superior operational stability.This study elucidates the underlying mechanisms limiting the efficiency of TSP p-i-n PSCs,while establishing design principles for these devices targeting 26%efficiency.展开更多
The presence of a surface oxide film(B_(2)O_(3))on boron(B)particles significantly compromises their combustion efficiency and kinetic performance in fuel-rich solid propellants.This study proposes an innovative conti...The presence of a surface oxide film(B_(2)O_(3))on boron(B)particles significantly compromises their combustion efficiency and kinetic performance in fuel-rich solid propellants.This study proposes an innovative continuous modification strategy combining non-thermal plasma(NTP)etching with fluorocarbon passivation.Characterization and kinetic analysis revealed that reactive plasma species—including atomic hydrogen(H),electronically excited molecular hydrogen(H_(2)^(*)),vibrationally excited molecular hydrogen(H_(2)v),and hydrogen ions(H^(+))—dominate the reduction of B_(2)O_(3)through lowering the transition energy barrier and shifting the reaction spontaneity.Subsequent argon plasma fragmentation of C_(8)F_(18)generates fluorocarbon radicals that form conformal passivation coatings(thickness:7 nm)on purified boron surfaces.The modified boron particles exhibit 37.5℃lower exothermic peak temperature and 27.2%higher heat release(14.8 kJ/g vs.11.6 kJ/g)compared to untreated counterparts.Combustion diagnostics reveal 194%increase in maximum flame height(135.10 mm vs.46.03 mm)and 134%enhancement in flame propagation rate(4.44 cm/s vs.1.90 cm/s).This NTP-based surface engineering approach establishes a scalable pathway for developing highperformance boron-based energetic composites.展开更多
In order to eliminate the meshing interference between the flexspline and circular spline after the taper deformation of the flexspline,the radial deformation difference method,major and minor axis fitting method,and ...In order to eliminate the meshing interference between the flexspline and circular spline after the taper deformation of the flexspline,the radial deformation difference method,major and minor axis fitting method,and ellipse fitting method are used to modify the tooth thickness of the flexspline and analyze the performance indexes such as the assembly stress,transmission error,and fatigue life.Firstly,the conjugate tooth profile is solved based on the quadruple-circular-arc tooth profile and modified kinematic method.Then,based on the finite element radial deformation of the flexspline,the principle and characteristics of three modification methods are analyzed,and the modification amount of each section of the flexspline tooth is calculated.Finally,the influence of the three modification methods on the performance of the harmonic drive is compared.The results show that the radial deformation difference method can initially determine the modification amount.The minimum static assembly stress is 406.22 MPa by the major and minor axis fitting method.The ellipse fitting method has the best dynamic performance,small transmission error fluctuation,a peak-to-peak value of 3.060",and a maximum fatigue life of 10^(7.558)cycles.展开更多
MnO_(x)-CeO_(2)catalysts for the low-temperature selective catalytic reduction(SCR)of NO remain vulnerable to water and sulfur poisoning,limting their practical applications.Herein,we report a hydrophobic-modified MnO...MnO_(x)-CeO_(2)catalysts for the low-temperature selective catalytic reduction(SCR)of NO remain vulnerable to water and sulfur poisoning,limting their practical applications.Herein,we report a hydrophobic-modified MnO_(x)-CeO_(2)catalyst that achieves enhanced NO conversion rate and stability under harsh conditions.The catalyst was synthesized by decorating MnOx crystals with amorphous CeO_(2),followed by loading hydrophobic silica on the external surfaces.The hydrophobic silica allowed the adsorption of NH_(3)and NO and diffusion of H,suppressed the adsorption of H_(2)O,and prevented SO_(2)interaction with the Mn active sites,achieving selective molecular discrimination at the catalyst surface.At 120℃,under H_(2)O and SO_(2)exposure,the optimal hydrophobic catalyst maintains 82%NO conversion rate compared with 69%for the unmodified catalyst.The average adsorption energies of NH_(3),H_(2)O,and SO_(2)decreased by 0.05,0.43,and 0.52 eV,respectively.The NO reduction pathway follows the Eley-Rideal mechanism,NH_(3)^(*)+*→NH_(2)^(*)+H^(*)followed by NH_(2)^(*)+NO^(*)→N_(2)^(*)+H_(2)O^(*),with NH_(3)dehydrogenation being the rate determining step.Hydrophobic modification increased the activation energy for H atom transfer,leading to a minor decrease in the NO conversion rate at 120℃.This work demonstrates a viable strategy for developing robust NH_(3)-S CR catalysts capable of efficient operation in water-and sulfur-rich environments.展开更多
We are sorry for the mistakes of Affiliation,"a State Key Laboratory of Advanced Fiber Materials,Center for Advanced Low-Dimension Materials,Donghua University,Shanghai 201620,China"should be replaced by&quo...We are sorry for the mistakes of Affiliation,"a State Key Laboratory of Advanced Fiber Materials,Center for Advanced Low-Dimension Materials,Donghua University,Shanghai 201620,China"should be replaced by"a State Key Laboratory of Advanced Fiber Materials,Center for Advanced Low-Dimension Materials,College of Materials Science and Engineering,Donghua University,Shanghai 201620,China".We apologized for the inconvenience caused by this error.展开更多
Chinese medicinal materials are the material basis for the inheritance and development of traditional Chinese medicine.Intellectual property protection for the entire industrial chain of traditional Chinese medicinal ...Chinese medicinal materials are the material basis for the inheritance and development of traditional Chinese medicine.Intellectual property protection for the entire industrial chain of traditional Chinese medicinal materials promotes the inheritance and innovation of traditional Chinese medicine,and contributes to rural revitalization and the building of an agricultural power.This article provides an overview of the traditional Chinese medicinal materials in Hubei Province.It conducts a detailed investigation into the intellectual property resources of the province s traditional Chinese medicinal materials from aspects such as traditional knowledge,genetic resources,new plant varieties,patents,geographical indications,and trademarks.It analyzes the eight main problems in the protection,inheritance,and innovative development of intellectual property rights,and puts forward corresponding suggestions,such as establishing an intellectual property rights rule system for specific fields of traditional Chinese medicinal materials,promoting the"Famous Brand Action in Rural Areas",and building a"Hubei s Sixteen Superior Herbs"cluster of traditional Chinese medicinal materials.展开更多
The neuroinflammatory response mediated by microglial activation plays an important role in the secondary nerve injury of traumatic brain injury.The post-transcriptional modification of N^(6)-methyladenosine is ubiqui...The neuroinflammatory response mediated by microglial activation plays an important role in the secondary nerve injury of traumatic brain injury.The post-transcriptional modification of N^(6)-methyladenosine is ubiquitous in the immune response of the central nervous system.The fat mass and obesity-related protein catalyzes the demethylation of N^(6)-methyladenosine modifications on mRNA and is widely expressed in various tissues,participating in the regulation of multiple diseases’biological processes.However,the role of fat mass and obesity in microglial activation and the subsequent neuroinflammatory response after traumatic brain injury is unclear.In this study,we found that the expression of fat mass and obesity was significantly down-regulated in both lipopolysaccharide-treated BV2 cells and a traumatic brain injury mouse model.After fat mass and obesity interference,BV2 cells exhibited a pro-inflammatory phenotype as shown by the increased proportion of CD11b^(+)/CD86^(+)cells and the secretion of pro-inflammatory cytokines.Fat mass and obesity-mediated N^(6)-methyladenosine demethylation accelerated the degradation of ADAM17 mRNA,while silencing of fat mass and obesity enhanced the stability of ADAM17 mRNA.Therefore,down-regulation of fat mass and obesity expression leads to the abnormally high expression of ADAM17 in microglia.These results indicate that the activation of microglia and neuroinflammatory response regulated by fat mass and obesity-related N^(6)-methyladenosine modification plays an important role in the pro-inflammatory process of secondary injury following traumatic brain injury.展开更多
Research into lactylation modifications across various target organs in both health and disease has gained significant attention.Many essential life processes and the onset of diseases are not only related to protein ...Research into lactylation modifications across various target organs in both health and disease has gained significant attention.Many essential life processes and the onset of diseases are not only related to protein abundance but are also primarily regulated by various post-translational protein modifications.Lactate,once considered merely a byproduct of anaerobic metabolism,has emerged as a crucial energy substrate and signaling molecule involved in both physiological and pathological processes within the nervous system.Furthermore,recent studies have emphasized the significant role of lactate in numerous neurological diseases,including Alzheimer's disease,Parkinson's disease,acute cerebral ischemic stroke,multiple sclerosis,Huntington's disease,and myasthenia gravis.The purpose of this review is to synthesize the current research on lactate and lactylation modifications in neurological diseases,aiming to clarify their mechanisms of action and identify potential therapeutic targets.As such,this work provides an overview of the metabolic regulatory roles of lactate in various disorders,emphasizing its involvement in the regulation of brain function.Additionally,the specific mechanisms of brain lactate metabolism are discussed,suggesting the unique roles of lactate in modulating brain function.As a critical aspect of lactate function,lactylation modifications,including both histone and non-histone lactylation,are explored,with an emphasis on recent advancements in identifying the key regulatory enzymes of such modifications,such as lactylation writers and erasers.The effects and specific mechanisms of abnormal lactate metabolism in diverse neurological diseases are summarized,revealing that lactate acts as a signaling molecule in the regulation of brain functions and that abnormal lactate metabolism is implicated in the progression of various neurological disorders.Future research should focus on further elucidating the molecular mechanisms underlying lactate and lactylation modifications and exploring their potential as therapeutic targets for neurological diseases.展开更多
The large volume expansion and rapid capacity attenuation of tin-based electrodes are the main factors limiting their commercial application.The reasonable design of electrode material structure is particularly import...The large volume expansion and rapid capacity attenuation of tin-based electrodes are the main factors limiting their commercial application.The reasonable design of electrode material structure is particularly important for improving its electrochemical performance.Herein,phosphorus-modified graphene encapsulated Sn_(6)O_(4)(OH)_(4)nanoparticles composite(P-Sn_(6)O_(4)(OH)_(4)@RGO)with crystalline-amorphous heterostructure has been successfully designed and prepared.The design of crystalline-amorphous structure has largely enhanced the active sites,and the construction of a graphene encapsulation structure has greatly alleviated volume expansion.Notably,P-Sn_(6)O_(4)(OH)_(4)@RGO obtained an excellent high-rate longterm cycling performance for lithium-ion batteries anode,reaching a high specific capacity of 970 m Ah/g at 1.0 A/g after 1450 cycles.This work demonstrates that restructuring the electrode material's structure and phase through phosphorus modification can effectively improve the electrochemical performance of tin-based electrode materials.展开更多
In recent years,exosomes have garnered extensive attention as therapeutic agents and early diagnostic markers in neurodegenerative disease research.Exosomes are small and can effectively cross the blood-brain barrier,...In recent years,exosomes have garnered extensive attention as therapeutic agents and early diagnostic markers in neurodegenerative disease research.Exosomes are small and can effectively cross the blood-brain barrier,allowing them to target deep brain lesions.Recent studies have demonstrated that exosomes derived from different cell types may exert therapeutic effects by regulating the expression of various inflammatory cytokines,mRNAs,and disease-related proteins,thereby halting the progression of neurodegenerative diseases and exhibiting beneficial effects.However,exosomes are composed of lipid bilayer membranes and lack the ability to recognize specific target cells.This limitation can lead to side effects and toxicity when they interact with non-specific cells.Growing evidence suggests that surface-modified exosomes have enhanced targeting capabilities and can be used as targeted drug-delivery vehicles that show promising results in the treatment of neurodegenerative diseases.In this review,we provide an up-to-date overview of existing research aimed at devising approaches to modify exosomes and elucidating their therapeutic potential in neurodegenerative diseases.Our findings indicate that exosomes can efficiently cross the blood-brain barrier to facilitate drug delivery and can also serve as early diagnostic markers for neurodegenerative diseases.We introduce the strategies being used to enhance exosome targeting,including genetic engineering,chemical modifications(both covalent,such as click chemistry and metabolic engineering,and non-covalent,such as polyvalent electrostatic and hydrophobic interactions,ligand-receptor binding,aptamer-based modifications,and the incorporation of CP05-anchored peptides),and nanomaterial modifications.Research into these strategies has confirmed that exosomes have significant therapeutic potential for neurodegenerative diseases.However,several challenges remain in the clinical application of exosomes.Improvements are needed in preparation,characterization,and optimization methods,as well as in reducing the adverse reactions associated with their use.Additionally,the range of applications and the safety of exosomes require further research and evaluation.展开更多
I.INTRODUCTION Against the backdrop of profound transformations in the global energy landscape,China,as the world's largest energy producer and consumer,faces multiple challenges,including energy security,energy t...I.INTRODUCTION Against the backdrop of profound transformations in the global energy landscape,China,as the world's largest energy producer and consumer,faces multiple challenges,including energy security,energy transition,and sustainable development.To address these challenges,the Chinese government has formulated a strategic plan to build a unified national energy market and create a new framework for the energy sector.Article 42 of the Energy Law of the People's Republic of China(hereinafter referred to as the Energy Law)explicitly requires the building of a unified national energy trading market and the improvement of transaction mechanisms and rules.展开更多
A bisphenol epoxy resin was used as modifier to increase the heat resistance of condensed poly-nuclear aromatic （COPNA） resin. The basic properties of COPNA resin and modified resin were characterized by Fourier tra...A bisphenol epoxy resin was used as modifier to increase the heat resistance of condensed poly-nuclear aromatic （COPNA） resin. The basic properties of COPNA resin and modified resin were characterized by Fourier transform infrared spectroscopy （FT-IR）, nuclear magnetic resonance spectroscopy （1H-NMR）, vapor pressure osmometry （VPO） and elemental analysis （EA）. Average structural parameters of resins were calculated by the improved Brown-Ladner method, and heat resistance of resins was tested by thermogravimetric analysis （TGA）. The chemical structure, mechanical properties and heat resistivity of the resin/graphite composites prepared with different resins were compared. The results show that the adhesive property and heat resistance of COPNA resin can be remarkably improved by addition of 5 wt.% epoxy resin. The reason is that the reactions between epoxy groups of epoxy resin and hydroxyl groups of COPNA resin improve the heat resistance and adhesive property of COPNA resin. Electric motor brushes with good mechanical properties and low electrical resistivity were successfully prepared by using the modified resin as binder.展开更多
In general, the modification performance of AI-Sr master alloys is primarily dependent upon the morphologies and sizes of the AI4Sr intermetallic phase. In this paper, the crystal structure, morphologies, sizes, hardn...In general, the modification performance of AI-Sr master alloys is primarily dependent upon the morphologies and sizes of the AI4Sr intermetallic phase. In this paper, the crystal structure, morphologies, sizes, hardness and elastic modulus of AI4Sr in AI-Sr master alloys prepared from variant processes were studied by means of optical metallurgical microscope, X-ray diffraction （XRD）, scanning electron microscopy （SEM）, and nanoindentation system. The results revealed that the microstructures and modification performance of the AI4Sr phase were related to the preparation processes. That is to say, when a ＂direct reaction-hot extrusion＂ process was used, the AI4Sr phase exhibited a homogeneous distribution in the AI matrix with small size and roundish shapes, which ensured the AI-Sr master alloy wire advantages involving high recovery, good reproducibility, no delitescence of modification, no corrosion on equipments, and good workability. However, in the case of the traditional ＂direct reaction＂ process, the AI4Sr phase was in large size with shapes of rectangular stripe and plates, which limited the Sr content increasing due to the brittleness of the AI-Sr alloy. It was also found that the morphology and size of the AI4Sr phases changed during heat treatment at high temperature up to 600℃.展开更多
基金supported by the National Natural Science Foundation of China(22308006 and 22278001)the Natural Science Foundation of Anhui Provincial Education Department(KJ2021A0407).
文摘Polystyrene(PS)waste was depolymerized using a low-temperature pyrolysis treatment(LTPT)to increase its caking index.The mechanism of caking index modification was revealed by using Fourier transform infrared spectroscopy,thermogravimetric(TG)analysis,pyrolysis-gas chromatography with mass spectrometric detection,and solid-state^(13)C nuclear magnetic resonance spectroscopy.The crucible coal-blending coking tests were carried out using an industrial coal mixture and the treated-PS with the highest caking index(PS300)or raw PS.Some properties of the resultant cokes were also analyzed.It was demonstrated that the caking index of PS dramatically increased by LTPT;however,exceeding 300℃ did not yield any benefit.The caking index increased due to the formation of the caking components,whose molecules are medium in size,caused by LTPT.Additionally,the coke reactivity index of the coke obtained from the mixture containing PS300 decreased by 5.1%relative to that of the coke made from the mixture with PS and the coke strength after reaction index of the former increased by 7.3% compared with that of the latter,suggesting that the ratio of depolymerized PS used for coal-blending coking could increase relative to that of PS.
基金Supported by Design and Performance Study of High-flux Metal Hydride Reactor Based on the Bionic Optimization(2078262)the‘Four-Chain’Integration Project at the Qinchuangyuan Chief Platform(S2025-YF-ZDXM)。
文摘As one of the most promising new energy sources,hydrogen energy is expected to usher in a full-fledged“hydrogen economy”in the 21st century.Compared with traditional high-pressure gaseous and cryogenic liquid hydrogen storage methods,solid-state chemical hydrogen storage shows significant advantages in safety,high efficiency,and cost-effectiveness.Magnesium-based lightweight hydrogen storage materials have attracted widespread attention due to their high gravimetric hydrogen storage density(7.6%)and favorable reversibility.However,their sluggish reaction kinetics and stringent operating conditions(with H2 release temperatures exceeding 350°C and H2 absorption pressures above 4 MPa)pose major challenges for practical applications.Domestic and international researchers have conducted in-depth studies to address these issues,achieving substantial progress in the modification of magnesium-based hydrogen storage alloys.This paper systematically elaborates on major modification techniques such as alloying,nanostructuring,and catalytic material doping,providing a comprehensive analysis of the strengths and limitations of each approach.Furthermore,it offers prospects for the future development of magnesium-based hydrogen storage materials by integrating current theoretical and experimental research findings.
文摘Biomass-derived carbon materials are favored for their abundance and sustainability,and ease of preparation and modification.By surface activation and modification they can have a good electrical conductivity,excellent catalytic activity,a remarkable adsorption capacity,and different interfacial physicochemical functionalities.Surface-modified biochars have found wide applications in energy storage,environmental remediation,and catalysis.However,achieving precise and controllable modification of their active sites remains a challenge.Recent advances and future prospects for controlling their surface morphology,defect engineering,and surface coating strategies,with particular attention to their means of fabrication,are reviewed.
基金supported by the National Natural Science Foundation of China(Nos.82573045,82460602,82560459)the Hainan Provincial Graduate Student Innovative Research Project(No.Qhys2024-440).
文摘Post-translational modifications(PTMs)regulate the occurrence and development of cancer,and lactylation modification is a new form of PTMs.Recent studies have found that lactic acid modification can regulate the immune tolerance of cancer cells.The classical theory holds that prostate apoptosis response-4(PAR-4)is a tumor suppressor protein.However,our recent research has found that PAR-4 has a biological function of promoting cancer in hepatocellular carcinoma(HCC),and our analysis shows that PAR-4 can be modified of lactic acid.These research evidences suggest that PAR-4 lactylation modification may drive immune tolerance in HCC.Therefore,inhibiting PAR-4 lactylation modification is very likely to increase the sensitivity of HCC to immunotherapy.
基金financial support by the National Key Research and Development Program of China(No.2023YFC2907801)the Hunan Provincial Natural Science Foundation of China(No.2023JJ40760)the Scientific and Technological Project of Yunnan Precious Metals Laboratory,China(No.YPML-2023050276)。
文摘Bentonite is a necessary binder in producing pellets.Its excessive use reduces the iron grade of pellets and increases production costs.Minimizing bentonite dosage is essential for producing high-quality iron ore pellets.Addressing the gap in the application of organically-intercalated modified bentonite in the pelletizing field,this study introduces an innovative modification process for bentonite that employs the synergistic effect of mechanical force and dimethyl sulfoxide to enhance the intercalation of organic compounds within bentonite,thus significantly enhancing its binding performance.The colloid value and swell capacity of modified bentonite(98.5 m L/3g and 55.0 m L/g)were much higher than the original bentonite(90.5 m L/3g and 17.5 m L/g).With the decrease of bentonite dosage from1.5wt%to 1.0wt%,the drop number of green pellets from a height of 0.5 m and the compressive strengths of roasted pellets using the modified bentonite(6.0 times and 2916 N per pellet)were significantly higher than those of the original bentonite(4.0 times and 2739 N per pellet).This study provides a comprehensive analysis of the intercalation modification mechanism of bentonite,offering crucial technical insights for the development of high-performance modified bentonite as iron ore pellet binders.
基金supported by the National Natural Science Foundation of China (52302259)the China Postdoctoral Science Foundation (CPSF) under Grant Number 2023M741479+4 种基金the Postdoctoral Fellowship Program of CPSF under Grant Number GZB20240280the Jiangxi Provincial Natural Science Foundation (20224ACB218006)the financial support from High-level Talent Research Special Funds of Jiangxi University of Science and Technology (Grant No. 205200100670)the Jiangxi Provincial Key Laboratory of Power Energy Storage Batteries and Materials (2024SSY10011)the Major Scientific and Technological Research R&D Special Project of Jiangxi Province(20244AFI92002)
文摘The implementation of multifunctional application scenarios for mobile terminal devices has increased the energy density requirements of batteries.Increasing the charging voltage can rapidly increase the specific capacity of layered transition metal oxides;however,it also exacerbates the release of lattice oxygen and the contraction of the unit cell.Ternary materials are designed in a secondary particle state to meet the requirements of power battery applications.Therefore,to create ternary materials that can operate under ultrahigh voltages,attention should be given to both surface modification and particle integrity maintenance.By utilizing elemental selenium(Se)with a low melting point,easy sublimation,and multiple variable valence states,deep grain boundary modification was implemented inside the particles.The performance of the cathode material was evaluated through pouch cells,and the improvement mechanism was explored through molecular dynamics simulation calculations.Under the protection of a three-dimensional Se-rich modified layer,LiNi_(1/3)Co_(1/3)Mn_(1/3)O_(2)achieved stable operation at ultrahigh voltages(4.6 V vs.Li/Li^(+));a sacrificial protection mechanism based on the chronic decomposition of the Se-rich layer was proposed to explain the efficacy of Se modification in stabilizing ternary materials.This deep grain boundary modification based on elemental Se provides a new solution for the ultrahigh-voltage operation of transition metal oxides and provides a scientific basis and technical support for solving the interface contact problem of all-solid-state batteries.
基金supported by grants from the National Natural Science Foundation of China(Grant Nos.22334007).
文摘Perovskite solar cells have achieved remarkable progress in photovoltaic efficiency.However,interfacial defects at the buried and upper interfaces of perovskite layer remain a critical challenge,leading to charge recombination,ion migration,and iodine oxidation.To address this,we propose a novel all-in-one modification strategy employing ammonia borane(BNH6)as a multifunctional complex.By incorporating BNH6 at both buried and upper interfaces simultaneously,we achieve dualinterfacial defect passivation and iodide oxidation suppression through three key mechanisms:(1)hydrolysis-induced interaction with SnO_(2),(2)coordination with Pb^(2+),and(3)inhibition of I−oxidation.This approach significantly enhances device performance,yielding a champion power conversion efficiency(PCE)of 26.43%(certified 25.98%).Furthermore,the unencapsulated device demonstrates prominent enhanced operation stability,maintaining 90%of its initial PCE after 500 h under continuous illumination.Notably,our strategy eliminates the need for separate interface treatments,streamlining fabrication and offering a scalable route toward high-performance perovskite photovoltaics.
基金supported by the National Nature Science Foundation of China(62504130)National Key Research and Development Program of China(2018YFB0704100)+1 种基金the Key university laboratory of highly efficient utilization of solar energy and sustainable development of Guangdong(Y01256331)the Technology Development Project of Henan Province(252102240047).
文摘Two-step-processed(TSP)inverted p-i-n perovskite solar cells(PSCs)have demonstrated significant promise in tandem applications.However,the power conversion efficiency(PCE)of TSP p-i-n PSCs rarely exceeds 24%.Here,we demonstrate that TSP perovskite films exhibit a vertically gradient distribution of residual PbI_(2)clusters,which form Schottky heterojunctions with the perovskite,leading to substantial interfacial energy-level mismatches within NiO_(x)-based TSP p-i-n PSCs.These limitations were effectively addressed via a vertical interfacial engineering enabled by dual-interface modification incorporating tin trifluoromethanesulfonate(Sn(OTF)_(2))and 4-Fluorophenylethylamine chloride(F-PEA)at the NiO_(x)/perovskite and perovskite/C60 interfaces,respectively.The functional Sn(OTF)_(2)not only enhances the conductivity of NiO_(x)films but also suppresses ion migration,while inducing the formation of a Pb-Sn mixed perovskite interlayer that precisely regulates the energy level at the NiO_(x)/perovskite interface.Complementally,F-PEA post-treatment effectively converts surface residual PbI_(2)clusters into a 2D perovskite capping layer,which simultaneously passivates surface defects and enhances energy-level alignment at the perovskite/C60 interface.Consequently,the optimized NiO_(x)-based TSP p-i-n PSCs achieve a notable PCE of 25.6%with superior operational stability.This study elucidates the underlying mechanisms limiting the efficiency of TSP p-i-n PSCs,while establishing design principles for these devices targeting 26%efficiency.
基金supported by the National Natural Science Foundation of China(Nos.U2341249,12005076,22205112)the Fundamental Research Funds for the Central Universities(No.2025201012)。
文摘The presence of a surface oxide film(B_(2)O_(3))on boron(B)particles significantly compromises their combustion efficiency and kinetic performance in fuel-rich solid propellants.This study proposes an innovative continuous modification strategy combining non-thermal plasma(NTP)etching with fluorocarbon passivation.Characterization and kinetic analysis revealed that reactive plasma species—including atomic hydrogen(H),electronically excited molecular hydrogen(H_(2)^(*)),vibrationally excited molecular hydrogen(H_(2)v),and hydrogen ions(H^(+))—dominate the reduction of B_(2)O_(3)through lowering the transition energy barrier and shifting the reaction spontaneity.Subsequent argon plasma fragmentation of C_(8)F_(18)generates fluorocarbon radicals that form conformal passivation coatings(thickness:7 nm)on purified boron surfaces.The modified boron particles exhibit 37.5℃lower exothermic peak temperature and 27.2%higher heat release(14.8 kJ/g vs.11.6 kJ/g)compared to untreated counterparts.Combustion diagnostics reveal 194%increase in maximum flame height(135.10 mm vs.46.03 mm)and 134%enhancement in flame propagation rate(4.44 cm/s vs.1.90 cm/s).This NTP-based surface engineering approach establishes a scalable pathway for developing highperformance boron-based energetic composites.
文摘In order to eliminate the meshing interference between the flexspline and circular spline after the taper deformation of the flexspline,the radial deformation difference method,major and minor axis fitting method,and ellipse fitting method are used to modify the tooth thickness of the flexspline and analyze the performance indexes such as the assembly stress,transmission error,and fatigue life.Firstly,the conjugate tooth profile is solved based on the quadruple-circular-arc tooth profile and modified kinematic method.Then,based on the finite element radial deformation of the flexspline,the principle and characteristics of three modification methods are analyzed,and the modification amount of each section of the flexspline tooth is calculated.Finally,the influence of the three modification methods on the performance of the harmonic drive is compared.The results show that the radial deformation difference method can initially determine the modification amount.The minimum static assembly stress is 406.22 MPa by the major and minor axis fitting method.The ellipse fitting method has the best dynamic performance,small transmission error fluctuation,a peak-to-peak value of 3.060",and a maximum fatigue life of 10^(7.558)cycles.
基金financially sponsored by the National Natural Science Foundation of China(No.52204414)the National Energy-Saving and Low-Carbon Materials Production and Application Demonstration Platform Program,China(No.TC220H06N)+1 种基金the National Key R&D Program of China(No.2021YFC1910504)the Fundamental Research Funds for the Central Universities,China(No.FRFTP-20-097A1Z)。
文摘MnO_(x)-CeO_(2)catalysts for the low-temperature selective catalytic reduction(SCR)of NO remain vulnerable to water and sulfur poisoning,limting their practical applications.Herein,we report a hydrophobic-modified MnO_(x)-CeO_(2)catalyst that achieves enhanced NO conversion rate and stability under harsh conditions.The catalyst was synthesized by decorating MnOx crystals with amorphous CeO_(2),followed by loading hydrophobic silica on the external surfaces.The hydrophobic silica allowed the adsorption of NH_(3)and NO and diffusion of H,suppressed the adsorption of H_(2)O,and prevented SO_(2)interaction with the Mn active sites,achieving selective molecular discrimination at the catalyst surface.At 120℃,under H_(2)O and SO_(2)exposure,the optimal hydrophobic catalyst maintains 82%NO conversion rate compared with 69%for the unmodified catalyst.The average adsorption energies of NH_(3),H_(2)O,and SO_(2)decreased by 0.05,0.43,and 0.52 eV,respectively.The NO reduction pathway follows the Eley-Rideal mechanism,NH_(3)^(*)+*→NH_(2)^(*)+H^(*)followed by NH_(2)^(*)+NO^(*)→N_(2)^(*)+H_(2)O^(*),with NH_(3)dehydrogenation being the rate determining step.Hydrophobic modification increased the activation energy for H atom transfer,leading to a minor decrease in the NO conversion rate at 120℃.This work demonstrates a viable strategy for developing robust NH_(3)-S CR catalysts capable of efficient operation in water-and sulfur-rich environments.
文摘We are sorry for the mistakes of Affiliation,"a State Key Laboratory of Advanced Fiber Materials,Center for Advanced Low-Dimension Materials,Donghua University,Shanghai 201620,China"should be replaced by"a State Key Laboratory of Advanced Fiber Materials,Center for Advanced Low-Dimension Materials,College of Materials Science and Engineering,Donghua University,Shanghai 201620,China".We apologized for the inconvenience caused by this error.
基金Supported by the Project of National Social Science Fund of China(22CMZ015).
文摘Chinese medicinal materials are the material basis for the inheritance and development of traditional Chinese medicine.Intellectual property protection for the entire industrial chain of traditional Chinese medicinal materials promotes the inheritance and innovation of traditional Chinese medicine,and contributes to rural revitalization and the building of an agricultural power.This article provides an overview of the traditional Chinese medicinal materials in Hubei Province.It conducts a detailed investigation into the intellectual property resources of the province s traditional Chinese medicinal materials from aspects such as traditional knowledge,genetic resources,new plant varieties,patents,geographical indications,and trademarks.It analyzes the eight main problems in the protection,inheritance,and innovative development of intellectual property rights,and puts forward corresponding suggestions,such as establishing an intellectual property rights rule system for specific fields of traditional Chinese medicinal materials,promoting the"Famous Brand Action in Rural Areas",and building a"Hubei s Sixteen Superior Herbs"cluster of traditional Chinese medicinal materials.
基金supported by grants from the Major Projects of Health Science Research Foundation for Middle-Aged and Young Scientist of Fujian Province,China,No.2022ZQNZD01010010the National Natural Science Foundation of China,No.82371390Fujian Province Scientific Foundation,No.2023J01725(all to XC).
文摘The neuroinflammatory response mediated by microglial activation plays an important role in the secondary nerve injury of traumatic brain injury.The post-transcriptional modification of N^(6)-methyladenosine is ubiquitous in the immune response of the central nervous system.The fat mass and obesity-related protein catalyzes the demethylation of N^(6)-methyladenosine modifications on mRNA and is widely expressed in various tissues,participating in the regulation of multiple diseases’biological processes.However,the role of fat mass and obesity in microglial activation and the subsequent neuroinflammatory response after traumatic brain injury is unclear.In this study,we found that the expression of fat mass and obesity was significantly down-regulated in both lipopolysaccharide-treated BV2 cells and a traumatic brain injury mouse model.After fat mass and obesity interference,BV2 cells exhibited a pro-inflammatory phenotype as shown by the increased proportion of CD11b^(+)/CD86^(+)cells and the secretion of pro-inflammatory cytokines.Fat mass and obesity-mediated N^(6)-methyladenosine demethylation accelerated the degradation of ADAM17 mRNA,while silencing of fat mass and obesity enhanced the stability of ADAM17 mRNA.Therefore,down-regulation of fat mass and obesity expression leads to the abnormally high expression of ADAM17 in microglia.These results indicate that the activation of microglia and neuroinflammatory response regulated by fat mass and obesity-related N^(6)-methyladenosine modification plays an important role in the pro-inflammatory process of secondary injury following traumatic brain injury.
基金supported by Applied Basic Research Joint Fund Project of Yunnan Province,No.202301AY070001-200Middle-aged Academic and Technical Training Project for High-Level Talents,No.202105AC160065+1 种基金Yunnan Clinical Medical Center for Neurological and Cardiovascular Diseases,No.YWLCYXZX2023300077Key Clinical Specialty of Neurology in Yunnan Province,No.300064(all to CL)。
文摘Research into lactylation modifications across various target organs in both health and disease has gained significant attention.Many essential life processes and the onset of diseases are not only related to protein abundance but are also primarily regulated by various post-translational protein modifications.Lactate,once considered merely a byproduct of anaerobic metabolism,has emerged as a crucial energy substrate and signaling molecule involved in both physiological and pathological processes within the nervous system.Furthermore,recent studies have emphasized the significant role of lactate in numerous neurological diseases,including Alzheimer's disease,Parkinson's disease,acute cerebral ischemic stroke,multiple sclerosis,Huntington's disease,and myasthenia gravis.The purpose of this review is to synthesize the current research on lactate and lactylation modifications in neurological diseases,aiming to clarify their mechanisms of action and identify potential therapeutic targets.As such,this work provides an overview of the metabolic regulatory roles of lactate in various disorders,emphasizing its involvement in the regulation of brain function.Additionally,the specific mechanisms of brain lactate metabolism are discussed,suggesting the unique roles of lactate in modulating brain function.As a critical aspect of lactate function,lactylation modifications,including both histone and non-histone lactylation,are explored,with an emphasis on recent advancements in identifying the key regulatory enzymes of such modifications,such as lactylation writers and erasers.The effects and specific mechanisms of abnormal lactate metabolism in diverse neurological diseases are summarized,revealing that lactate acts as a signaling molecule in the regulation of brain functions and that abnormal lactate metabolism is implicated in the progression of various neurological disorders.Future research should focus on further elucidating the molecular mechanisms underlying lactate and lactylation modifications and exploring their potential as therapeutic targets for neurological diseases.
基金supported by the Natural Science Foundation of Shandong Province(Nos.ZR2024QE450,ZR2024QB302 and ZR2024QB004)the Taishan Scholars and Young Experts Program of Shandong Province(No.tsqn202211249)Research Program of Qilu Institute of Technology(Nos.QIT 23TP019,QIT23TP010 and QIT24NN007)。
文摘The large volume expansion and rapid capacity attenuation of tin-based electrodes are the main factors limiting their commercial application.The reasonable design of electrode material structure is particularly important for improving its electrochemical performance.Herein,phosphorus-modified graphene encapsulated Sn_(6)O_(4)(OH)_(4)nanoparticles composite(P-Sn_(6)O_(4)(OH)_(4)@RGO)with crystalline-amorphous heterostructure has been successfully designed and prepared.The design of crystalline-amorphous structure has largely enhanced the active sites,and the construction of a graphene encapsulation structure has greatly alleviated volume expansion.Notably,P-Sn_(6)O_(4)(OH)_(4)@RGO obtained an excellent high-rate longterm cycling performance for lithium-ion batteries anode,reaching a high specific capacity of 970 m Ah/g at 1.0 A/g after 1450 cycles.This work demonstrates that restructuring the electrode material's structure and phase through phosphorus modification can effectively improve the electrochemical performance of tin-based electrode materials.
基金supported by the National Natural Science Foundation of China,No.22103055(to JG)the Natural Science Foundation of Hebei Province,No.F2024110001(to HC)Open Project of Tianjin Key Laboratory of Optoelectronic Detection Technology and System,Nos.2024LODTS215(to NL),2024LODTS216(to XS).
文摘In recent years,exosomes have garnered extensive attention as therapeutic agents and early diagnostic markers in neurodegenerative disease research.Exosomes are small and can effectively cross the blood-brain barrier,allowing them to target deep brain lesions.Recent studies have demonstrated that exosomes derived from different cell types may exert therapeutic effects by regulating the expression of various inflammatory cytokines,mRNAs,and disease-related proteins,thereby halting the progression of neurodegenerative diseases and exhibiting beneficial effects.However,exosomes are composed of lipid bilayer membranes and lack the ability to recognize specific target cells.This limitation can lead to side effects and toxicity when they interact with non-specific cells.Growing evidence suggests that surface-modified exosomes have enhanced targeting capabilities and can be used as targeted drug-delivery vehicles that show promising results in the treatment of neurodegenerative diseases.In this review,we provide an up-to-date overview of existing research aimed at devising approaches to modify exosomes and elucidating their therapeutic potential in neurodegenerative diseases.Our findings indicate that exosomes can efficiently cross the blood-brain barrier to facilitate drug delivery and can also serve as early diagnostic markers for neurodegenerative diseases.We introduce the strategies being used to enhance exosome targeting,including genetic engineering,chemical modifications(both covalent,such as click chemistry and metabolic engineering,and non-covalent,such as polyvalent electrostatic and hydrophobic interactions,ligand-receptor binding,aptamer-based modifications,and the incorporation of CP05-anchored peptides),and nanomaterial modifications.Research into these strategies has confirmed that exosomes have significant therapeutic potential for neurodegenerative diseases.However,several challenges remain in the clinical application of exosomes.Improvements are needed in preparation,characterization,and optimization methods,as well as in reducing the adverse reactions associated with their use.Additionally,the range of applications and the safety of exosomes require further research and evaluation.
基金research result of the Chongqing Social Science Fund Project,entitled Legal Pathways for the Governance Optimization of Financial Holding Companies(No.21SKJD036).
文摘I.INTRODUCTION Against the backdrop of profound transformations in the global energy landscape,China,as the world's largest energy producer and consumer,faces multiple challenges,including energy security,energy transition,and sustainable development.To address these challenges,the Chinese government has formulated a strategic plan to build a unified national energy market and create a new framework for the energy sector.Article 42 of the Energy Law of the People's Republic of China(hereinafter referred to as the Energy Law)explicitly requires the building of a unified national energy trading market and the improvement of transaction mechanisms and rules.
基金supported by the National Natural Science Foundation of China (Nos. 51172285, 51372277)the Fundamental Research Funds for the Central Universities (14CX02060A)the Natural Science Foundation of Shandong Province (ZR2011EL030)
文摘A bisphenol epoxy resin was used as modifier to increase the heat resistance of condensed poly-nuclear aromatic （COPNA） resin. The basic properties of COPNA resin and modified resin were characterized by Fourier transform infrared spectroscopy （FT-IR）, nuclear magnetic resonance spectroscopy （1H-NMR）, vapor pressure osmometry （VPO） and elemental analysis （EA）. Average structural parameters of resins were calculated by the improved Brown-Ladner method, and heat resistance of resins was tested by thermogravimetric analysis （TGA）. The chemical structure, mechanical properties and heat resistivity of the resin/graphite composites prepared with different resins were compared. The results show that the adhesive property and heat resistance of COPNA resin can be remarkably improved by addition of 5 wt.% epoxy resin. The reason is that the reactions between epoxy groups of epoxy resin and hydroxyl groups of COPNA resin improve the heat resistance and adhesive property of COPNA resin. Electric motor brushes with good mechanical properties and low electrical resistivity were successfully prepared by using the modified resin as binder.
基金supported by the National Basic Research Program of China ("973 Program",2009CB939705)the Hunan Jinlianxing Metallurgical Materials Technology Co.Ltd,China
文摘In general, the modification performance of AI-Sr master alloys is primarily dependent upon the morphologies and sizes of the AI4Sr intermetallic phase. In this paper, the crystal structure, morphologies, sizes, hardness and elastic modulus of AI4Sr in AI-Sr master alloys prepared from variant processes were studied by means of optical metallurgical microscope, X-ray diffraction （XRD）, scanning electron microscopy （SEM）, and nanoindentation system. The results revealed that the microstructures and modification performance of the AI4Sr phase were related to the preparation processes. That is to say, when a ＂direct reaction-hot extrusion＂ process was used, the AI4Sr phase exhibited a homogeneous distribution in the AI matrix with small size and roundish shapes, which ensured the AI-Sr master alloy wire advantages involving high recovery, good reproducibility, no delitescence of modification, no corrosion on equipments, and good workability. However, in the case of the traditional ＂direct reaction＂ process, the AI4Sr phase was in large size with shapes of rectangular stripe and plates, which limited the Sr content increasing due to the brittleness of the AI-Sr alloy. It was also found that the morphology and size of the AI4Sr phases changed during heat treatment at high temperature up to 600℃.
