To investigate the influence of Al-Zn-Mg-Cu alloy with as-homogenized and as-rolled initial microstructures on the tensile flow behavior,isothermal tensile tests were conducted on a GLEEBLE-3500 isothermal simulator a...To investigate the influence of Al-Zn-Mg-Cu alloy with as-homogenized and as-rolled initial microstructures on the tensile flow behavior,isothermal tensile tests were conducted on a GLEEBLE-3500 isothermal simulator at temperatures of 380-440℃and strain rates of 0.05-1 s^(−1).The Johnson-Cook model,Hensel-Spittel model,strain-compensated Arrhenius model,and critical fracture strain model were established.Results show that through the evaluation of the models using the correlation coefficient(R)and the average absolute relative error,the strain-compensated Arrhenius model can represent the flow behavior of the alloy more accurately.Shear bands are more pronounced in the as-homogenized specimens,whereas dynamic recrystallization is predominantly observed in as-rolled specimens.Fracture morphology analysis reveals that a mixed fracture mechanism is prevalent in the as-homogenized specimen,whereas a ductile fracture mechanism is predominant in the as-rolled specimen.The processing maps indicate that the unstable region is reduced in the as-rolled specimens compared with that in the as-homogenized specimens.The optimal hot working windows for the as-homogenized and as-rolled specimens are determined as 410-440℃/0.14-1 s^(−1)and 380-400℃/0.05-0.29 s^(−1),respectively.展开更多
Correction to:Nano-Micro Letters(2026)18:10.https://doi.org/10.1007/s40820-025-01852-8 Following publication of the original article[1],the authors reported that the last author’s name was inadvertently misspelled.Th...Correction to:Nano-Micro Letters(2026)18:10.https://doi.org/10.1007/s40820-025-01852-8 Following publication of the original article[1],the authors reported that the last author’s name was inadvertently misspelled.The published version showed“Hongzhen Chen”,whereas the correct spelling should be“Hongzheng Chen”.The correct author name has been provided in this Correction,and the original article[1]has been corrected.展开更多
This study utilizes wet/dry cyclic corrosion testing combined with corrosion big data technology to investigate the mechanism by which chloride ions(Cl^(-))influence the corrosion behavior of 650 MPa high-strength low...This study utilizes wet/dry cyclic corrosion testing combined with corrosion big data technology to investigate the mechanism by which chloride ions(Cl^(-))influence the corrosion behavior of 650 MPa high-strength low-alloy(HSLA)steel in industrially polluted environments.The corrosion process of 650 MPa HSLA steel occurred in two distinct stages:an initial corrosion stage and a stable corrosion stage.During the initial phase,the weight loss rate increased rapidly owing to the instability of the rust layer.Notably,this study demonstrated that 650 MPa HSLA steel exhibited superior corrosion resistance in Cl-containing environments.The formation of a corrosion-product film eventually reduced the weight-loss rate.However,the intrusion of Cl^(-)at increasing concentrations gradually destabilized theα/γ^(*)phases of the rust layer,leading to a looser structure and lower polarization resistance(R_(p)).The application of corrosion big data technology in this study facilitated the validation and analysis of the experimental results,offering new insights into the corrosion mechanisms of HSLA steel in chloride-rich environments.展开更多
The volume change behavior of natural gas hydrate-bearing sediment is essential as it influences settlement,strength,and stiffness,which directly affect the stability of hydrate reservoirs during hydrate extraction or...The volume change behavior of natural gas hydrate-bearing sediment is essential as it influences settlement,strength,and stiffness,which directly affect the stability of hydrate reservoirs during hydrate extraction or in response to environmental changes.The volume change is influenced not only by stress but also by the formation and dissociation of hydrates.This study adopted a customized apparatus for one-dimensional compression tests,allowing independent control of gas pressure and effective stress.Tests were conducted on samples with different hydrate saturations along various temperature-gas pressure-effective stress paths,yielding some conclusions related to compressibility and creep.An unusual phenomenon was observed under low-stress conditions:hydrate formation led to shrinkage rather than expansion.Three potential mechanisms behind this occurrence were discussed.As hydrate saturation increases,the yield stress rises while the compression and swelling indexes remain minimally affected.After hydrate dissociation,the compression curve of hydrate-bearing sediment drops to that of hydrate-free sediment.Once hydrate is formed,the compression curve of hydrate-free sediment gradually approaches that of hydrate-bearing sediment during the subsequent loading.Under low-stress conditions,the creep of both hydrate-free and hydrate-bearing sediments is very weak.However,when stress increases,significantly beyond the yield stress,the creep of both sediments increases significantly,with hydrate-bearing sediment exhibiting much greater creep than hydrate-free sediment.展开更多
Drilling and blasting tunneling is a cyclic process in which tunnel rock undergoes repeated blast loading,affecting its dynamic characteristics,energy evolution,and damage progression.To explore the dynamic mechanical...Drilling and blasting tunneling is a cyclic process in which tunnel rock undergoes repeated blast loading,affecting its dynamic characteristics,energy evolution,and damage progression.To explore the dynamic mechanical properties and damage mechanisms of carbonaceous slate under cyclic impact loads of varying intensities,cyclic dynamic tests are conducted using a triaxial split Hopkinson pressure bar.This study analyzes the stress-strain relationship,energy damage evolution,and macro-to-micro failure characteristics.The results show that peak stress and strain are significantly influenced by impact intensity and the number of impacts.The initial dynamic stress is positively correlated with the impact intensity,but with more impact,the dynamic stress decreases while the peak strain increases.Energy evolution follows a pattern of"slow growthfluctuating growthrapid growth,"with the crack initiation stress and its proportion decreasing.CT and SEM analyses reveal that as the impact intensity increases,failure becomes more chaotic,the fracture volume increases,and the fracture mode shifts from interlayer and intergranular to through-layer and trans-granular fractures.These findings provide an experimental basis for soft rock tunnel stability analysis.展开更多
BACKGROUND Despite societal guidelines recommending targeted screening for Barrett’s esophagus(BE)and esophageal adenocarcinoma(EAC)in individuals with gastroesophageal reflux symptoms(GERS),screening adherence is su...BACKGROUND Despite societal guidelines recommending targeted screening for Barrett’s esophagus(BE)and esophageal adenocarcinoma(EAC)in individuals with gastroesophageal reflux symptoms(GERS),screening adherence is suboptimal.Current screening approaches fail to identify individuals not seeking medical consultation for GERS or whose GERS are managed with‘over-the-counter’(OTC)acid suppressant therapies.AIM To assess patients’self-management and help-seeking behavior for GERS.METHODS This cross-sectional study collected data from the Dutch general population aged 18-75 years between January and April 2023 using a web-based survey.The survey included questions regarding self-management(e.g.,use of acid suppressant therapy with or without prescription)and help-seeking behavior(e.g.,consulting a primary care provider)for GERS.Simple random sampling was performed to select individuals within the target age group.In total,18156 randomly selected individuals were invited to participate.The study protocol was registered in ClinicalTrials.gov(identifier:NCT05689918).RESULTS Of the 18156 invited individuals,3214 participants(17.7%)completed the survey,of which 1572 participants(48.9%)reported GERS.Of these,904 participants(57.5%)had never consulted a primary care provider for these symptoms,of which 331 participants(36.6%)reported taking OTC acid suppressant therapy in the past six months and 100 participants(11.1%)fulfilled the screening criteria for BE and EAC according to the European Society of Gastrointestinal Endoscopy Guideline.CONCLUSION The population fulfilling the screening criteria for BE and EAC is incompletely identified,suggesting potential underutilization of medical consultation.Raising public awareness of GERS as a risk factor for EAC is needed.展开更多
Mesenchymal stem cell-derived extracellular vesicles have emerged as a promising form of regenerative and immunomodulatory therapy;indeed,micro(mi)RNAs contained within mesenchymal stem cell-derived extracellular vesi...Mesenchymal stem cell-derived extracellular vesicles have emerged as a promising form of regenerative and immunomodulatory therapy;indeed,micro(mi)RNAs contained within mesenchymal stem cell-derived extracellular vesicles modulate target gene expression and impact disease-associated pathways.Chronic alcohol consumption leads to neuroinflammation,brain damage,and impaired cognition.Evidence indicates that females are more vulnerable to alcohol-induced damage than males.While mesenchymal stem cell-derived extracellular vesicles have been studied in various neuroinflammatory conditions,their potential to counteract alcohol-induced brain damage remains unclear.In this study,we investigated whether repeated intravenous administration of mesenchymal stem cell-derived extracellular vesicles could ameliorate neuroinflammation and behavioral impairment induced by chronic alcohol consumption in female mice.Mesenchymal stem cell-derived extracellular vesicles diminished the increased binding of a micro-positron emission tomography tracer(^(18)F-FDG)when analyzing whole-brain 3D images and brain coronal sections of ethanol-treated mice.Mesenchymal stem cell-derived extracellular vesicle administration protected against ethanol-induced proinflammatory gene upregulation,cognitive dysfunction,and the conditioned rewarding effects of cocaine.MiRNA sequencing data from mesenchymal stem cell-derived extracellular vesicles revealed the elevated expression of extracellular vesicle-derived miR-483-5p and miR-140-3p in the brains of ethanol-treated female mice following mesenchymal stem cell-derived extracellular vesicle administration.In addition,mesenchymal stem cell-derived extracellular vesicles modulated the expression of pro-inflammatory-related miRNA target genes(e.g.,Socs3,Tnf,Mtor,and Atf6)in the brains of ethanol-treated female mice.These results suggest that mesenchymal stem cell-derived extracellular vesicles could function as a neuroprotective therapy to ameliorate the neuroinflammation,cognitive dysfunction,and conditioned rewarding effects of cocaine associated with chronic alcohol consumption.展开更多
This paper prepared a novel as-cast W-Zr-Ti metallic ESM using high-frequency vacuum induction melting technique.The above ESM performs a typical elastic-brittle material feature and strain rate strengthening behavior...This paper prepared a novel as-cast W-Zr-Ti metallic ESM using high-frequency vacuum induction melting technique.The above ESM performs a typical elastic-brittle material feature and strain rate strengthening behavior.The specimens exhibit violent chemical reaction during the fracture process under the impact loading,and the size distribution of their residual debris follows Rosin-Rammler model.The dynamic fracture toughness is obtained by the fitting of debris length scale,approximately 1.87 MPa·m~(1/2).Microstructure observation on residual debris indicates that the failure process is determined by primary crack propagation under quasi-static compression,while it is affected by multiple cracks propagation in both particle and matrix in the case of dynamic impact.Impact test demonstrates that the novel energetic fragment performs brilliant penetration and combustion effect behind the front target,leading to the effective ignition of fuel tank.For the brittleness of as-cast W-ZrTi ESM,further study conducted bond-based peridynamic(BB-PD)C++computational code to simulate its fracture behavior during penetration.The BB-PD method successfully captured the fracture process and debris cloud formation of the energetic fragment.This paper explores a novel as-cast metallic ESM,and provides an available numerical avenue to the simulation of brittle energetic fragment.展开更多
In the competitive retail industry of the digital era,data-driven insights into gender-specific customer behavior are essential.They support the optimization of store performance,layout design,product placement,and ta...In the competitive retail industry of the digital era,data-driven insights into gender-specific customer behavior are essential.They support the optimization of store performance,layout design,product placement,and targeted marketing.However,existing computer vision solutions often rely on facial recognition to gather such insights,raising significant privacy and ethical concerns.To address these issues,this paper presents a privacypreserving customer analytics system through two key strategies.First,we deploy a deep learning framework using YOLOv9s,trained on the RCA-TVGender dataset.Cameras are positioned perpendicular to observation areas to reduce facial visibility while maintaining accurate gender classification.Second,we apply AES-128 encryption to customer position data,ensuring secure access and regulatory compliance.Our system achieved overall performance,with 81.5%mAP@50,77.7%precision,and 75.7%recall.Moreover,a 90-min observational study confirmed the system’s ability to generate privacy-protected heatmaps revealing distinct behavioral patterns between male and female customers.For instance,women spent more time in certain areas and showed interest in different products.These results confirm the system’s effectiveness in enabling personalized layout and marketing strategies without compromising privacy.展开更多
The high-cycle fatigue fracture characteristics and damage mechanism of nickel-based single crystal superalloys at 850℃ was investigated.The results indicate that high-cycle fatigue cracks in single crystal superallo...The high-cycle fatigue fracture characteristics and damage mechanism of nickel-based single crystal superalloys at 850℃ was investigated.The results indicate that high-cycle fatigue cracks in single crystal superalloys generally originate from defect locations on the subsurface or interior of the specimen at 850℃.Under the condition of stress ratio R=0.05,as the fatigue load decreases,the high-cycle fatigue life gradually increases.The high-cycle fatigue fracture is mainly characterized by octahedral slip mechanism.At high stress and low lifespan,the fracture exhibits single or multiple slip surface features.Some fractures originate along a vertical small plane and then propagate along the{111}slip surface.At low stress and high lifespan,the fracture surface tend to alternate and expand along multiple slip planes after originating from subsurface or internal sources,exhibiting characteristics of multiple slip planes.Through electron backscatter diffraction and transmission electron microscope analysis,there is obvious oxidation behavior on the surface of the high-cycle fatigue fracture,and the fracture section is composed of oxidation layer,distortion layer,and matrix layer from the outside to the inside.Among them,the main components of the oxidation layer are oxides of Ni and Co.The distortion layer is mainly distributed in the form of elongated or short rod-shaped oxides of Al,Ta,and W.The matrix layer is a single crystal layer.Crack initiation and propagation mechanism were obtained by systematical analysis of a large number of highcycle fatigue fractures.In addition,the stress ratio of 0.05 is closer to the vibration mode of turbine blades during actual service,providing effective guidance for the study of failure and fracture mechanisms of turbine blades.展开更多
An energetic binder based on hydroxyl-terminated polybutadiene(HTPB),doped with different ratios of nitrocellulose(NC)(10%,20%,30%,and 50%),was developed to study the effect of NC doping on the thermal decomposition b...An energetic binder based on hydroxyl-terminated polybutadiene(HTPB),doped with different ratios of nitrocellulose(NC)(10%,20%,30%,and 50%),was developed to study the effect of NC doping on the thermal decomposition behavior of a composite propellant(CP)comprising ammonium nitrate(AN)as an oxidizer and magnesium(Mg)as a fuel.Optimization of the propellant formulation was conducted using Chemical Equilibrium with Applications-National Aeronautics and Space Administration(CEA-NASA)software,which demonstrated an increase in specific impulse by 12.09 s when the binder contained 50%NC.Fourier-transform infrared spectroscopy(FTIR)analysis confirmed the excellent compatibility between the components,and density measurements revealed an increase of 6.4%with a higher NC content.Morphological analysis using optical microscopy showed that NC doping improved the uniformity and compactness of the surface,reduced cavities,and achieved a more homogeneous particle distribution.Differential scanning calorimetry(DSC)analysis indicated a decrease in the decomposition temperature of the propellant as the NC content increased,while kinetic studies revealed a 48.68%reduction in the activation energy when 50%NC was incorporated into the binder.These findings suggest that the addition of NC enhances combustion efficiency and improves overall propellant performance.This study highlights the potential of the new HTPB-NC energetic binder as a promising approach for advancing solid propellant technology.展开更多
Diabetes mellitus(DM)has become one of the most serious and common chronic diseases around the world,leading to various complications and a reduction in life expectancy.Increased sedentary behavior(SB)and decreased ph...Diabetes mellitus(DM)has become one of the most serious and common chronic diseases around the world,leading to various complications and a reduction in life expectancy.Increased sedentary behavior(SB)and decreased physical activity(PA)are important contributors to the rising prevalence of DM.This article reviews the research progress on the pathogenesis of DM,the effects of SB and PA on the risk of DM,aiming to explore the influence of different PA intensities,amounts,frequencies,durations and types on the incidence of DM.Research has shown that blood glucose levels tend to increase with the prolongation of SB.Within a certain range,PA intensity and PA amount are negatively correlated with the risk of DM;Performing PA for more than 3 days per week maintains normal glucose tolerance and lower blood pressure;Engaging in 150–300 min of moderate intensity exercise or 75–150 min of high-intensity exercise per week reduces the risk of DM;PA during leisure time reduces the risk of DM,while PA during work increases the risk of DM;Both aerobic training and resistance training reduce the risk of DM,and the combination of the two training methods produces better benefits;Various types of exercises,such as cycling,soccer,aerobics,yoga,tai chi,all reduce the risk of DM.In summary,prolonged SB increases the risk of DM,while appropriate PA reduces the risk of DM.As the intensity,amount,and frequency of PA increase,the effect of reducing DM risk becomes more significant.Different exercise methods have different effects on reducing DM risk.展开更多
Four powder metallurgy(PM)Ni-based superalloys with different Hf and Ta contents were creep-tested at 650℃ and 970 MPa,700℃ and 770 MPa,and 750℃ and 580 MPa,respectively.The effect of Hf and Ta on creep deformation...Four powder metallurgy(PM)Ni-based superalloys with different Hf and Ta contents were creep-tested at 650℃ and 970 MPa,700℃ and 770 MPa,and 750℃ and 580 MPa,respectively.The effect of Hf and Ta on creep deformation behaviors of the superalloys was studied from multiple scales by SEM,electron backscatter diffraction(EBSD),and aberration-corrected scanning transmission electron microscope(AC-STEM).The results showed that Hf and Ta suppressed the intergranular fracture and initiation of cracks during the acceleration creep stage,which prolonged the creep rupture time.Hf and Ta inhibited the stacking faults extending and the dislocation climbing and promoted the Suzuki segregation of W during the steady-state creep stage,which reduced the minimum creep rate and delayed the start time of the acceleration creep stage.The Suzuki segregation of Co,Cr,Mo,Ti,Nb,W,and Ta along stacking faults was observed after Hf and Ta addition,leading to the localized phase transformation in the γ′phase,and the stacking fault phase was chemically disordered.This study provided ideas for the composition design of novel PM Ni-based superalloys and theoretical foundations for the combined addition of Hf and Ta.展开更多
Objective:This study aimed to examine the reliability and validity of the Chinese version of the Behavioral Inhibition System/Behavioral Activation System(BIS/BAS)scales among stroke survivors.Methods:The cross-sectio...Objective:This study aimed to examine the reliability and validity of the Chinese version of the Behavioral Inhibition System/Behavioral Activation System(BIS/BAS)scales among stroke survivors.Methods:The cross-sectional study was conducted at four comprehensive hospitals in Taizhou,Jiangsu,China.A sample of 232 first-ever stroke survivors were recruited from June to August 2023.Validity was examined using face validity and construct validity,which used confirmatory factor analysis(CFA)and known-group analysis.Reliability was evaluated by internal consistency and test-retest reliability.Results:The BIS/BAS scales demonstrated satisfactory face validity.The findings of CFAs supported the original four-factor structure of BAS-reward,BAS-drive,BAS-fun seeking,and BIS with acceptable model fit indices.Discriminative validity,assessed via known-group analysis,indicated that stroke survivors with probable depression had significantly lower mean BAS-reward,BAS-drive,and BAS-fun seeking scores(P<0.001)and a higher mean BIS score(P=0.028)compared to those without probable depression.The internal consistency,measured by Cronbach’s a coefficients for the subscales,ranged from 0.669 to 0.964.Test-retest reliability,assessed using intra-class correlation coefficients,ranged from 0.61 to 0.93.Conclusions:The Chinese version of the BIS/BAS scales could be a reliable and valid instrument for measuring behavioral activation among stroke survivors.展开更多
A novel precipitate-free Mg-0.1Sn anode with a homogeneous equal-axis grain structure was developed and rolled successfully at 573 K.Electrochemical test results indicate that the Mg-0.1Sn alloy exhibits enhanced anod...A novel precipitate-free Mg-0.1Sn anode with a homogeneous equal-axis grain structure was developed and rolled successfully at 573 K.Electrochemical test results indicate that the Mg-0.1Sn alloy exhibits enhanced anode dissolution kinetics.A Mg-air battery prepared using this anode exhibits a cell voltage of 1.626 V at 0.5 mA/cm^(2),reasonable anodic efficiency of 58.17%,and good specific energy of 1730.96 mW·h/g at 10 mA/cm^(2).This performance is attributed to the effective reactive anode surface,the suppressed chunk effect,and weak self-corrosion owing to the homogeneous basal texture.展开更多
Since the pioneering work by Broca and Wernicke in the 19th century,who examined individuals with brain lesions to associate them with specific behaviors,it was evident that behaviors are complex and cannot be fully a...Since the pioneering work by Broca and Wernicke in the 19th century,who examined individuals with brain lesions to associate them with specific behaviors,it was evident that behaviors are complex and cannot be fully attributable to specific brain areas alone.Instead,they involve connectivity among brain areas,whether close or distant.At that time,this approach was considered the optimal way to dissect brain circuitry and function.These pioneering efforts opened the field to explore the necessity or sufficiency of brain areas in controlling behavior and hence dissecting brain function.However,the connectivity of the brain and the mechanisms through which various brain regions regulate specific behaviors,either individually or collaboratively,remain largely elusive.Utilizing animal models,researchers have endeavored to unravel the necessity or sufficiency of specific brain areas in influencing behavior;however,no clear associations have been firmly established.展开更多
Magnesium matrix composites with both high strength and ductility have been achieved by introducing pure Ti particles.However,the properties of the surfaces of the composites need to be improved by surface technology,...Magnesium matrix composites with both high strength and ductility have been achieved by introducing pure Ti particles.However,the properties of the surfaces of the composites need to be improved by surface technology,such as micro-arc oxidation(MAO).In this study,we investigated the influence of the Ti-reinforcement phase on coating growth and evolution by subjecting both AZ91 alloy and AZ91/Ti composite to MAO treatment using silicate-based and phosphate-based electrolytes.Results revealed that the Ti-reinforcement phase influenced the MAO process,altering discharge behavior,and leading to a decreased cell voltage.The vigorous discharge of the Ti-reinforcement phase induced the formation of coating discharge channels,concurrently dissolving and oxidizing Ti-reinforcement to produce a composite ceramic coating with TiO2.The MAO coating on the AZ91/Ti composite exhibited a dark blue macromorphology and distinctive local micromorphological anomalies.In silicate electrolyte,a“volcano-like”localized morphology centered on the discharge channel emerged.In contrast,treatment in phosphate-based electrolyte resulted in a coating morphology similar to typical porous ceramic coatings,with visible radial discharge micropores at the reinforcement phase location.Compared to the AZ91 alloy,the coating on the AZ91/Ti composite exhibited lower thickness and higher porosity.MAO treatment reduced the self-corrosion current density of the AZ91/Ti surface by two orders of magnitude.The silicate coating demonstrated better corrosion resistance than the phosphate coating,attributed to its lower porosity.The formation mechanism of MAO coatings on AZ91/Ti composites in phosphate-based and silicate-based electrolytes was proposed.展开更多
Mitochondria play a crucial role as organelles,managing several physiological processes such as redox balance,cell metabolism,and energy synthesis.Initially,the assumption was that mitochondria primarily resided in th...Mitochondria play a crucial role as organelles,managing several physiological processes such as redox balance,cell metabolism,and energy synthesis.Initially,the assumption was that mitochondria primarily resided in the host cells and could exclusively transmit from oocytes to offspring by a mechanism known as vertical inheritance of mitochondria.Recent scholarly works,however,suggest that certain cell types transmit their mitochondria to other developmental cell types via a mechanism referred to as intercellular or horizontal mitochondrial transfer.This review details the process of which mitochondria are transferred across cells and explains the impact of mitochondrial transfer between cells on the efficacy and functionality of cancer cells in various cancer forms.Specifically,we review the role of mitochondria transfer in regulating cellular metabolism restoration,excess reactive oxygen species(ROS)generation,proliferation,invasion,metastasis,mitophagy activation,mitochondrial DNA(mtDNA)inheritance,immune system modulation and therapeutic resistance in cancer.Additionally,we highlight the possibility of using intercellular mitochondria transfer as a therapeutic approach to treat cancer and enhance the efficacy of cancer treatments.展开更多
High-strength Al-Zn-Mg-Cu alloys are widely utilized,but their strength deteriorates as strengthening precipitates coarsen rapidly at elevated temperatures,limiting their applications above 150℃.This study systematic...High-strength Al-Zn-Mg-Cu alloys are widely utilized,but their strength deteriorates as strengthening precipitates coarsen rapidly at elevated temperatures,limiting their applications above 150℃.This study systematically investigates the microstructure evolution and its impact on the properties of peak-aged Al-Zn-Mg-Cu alloys with varying Zn/Mg ratios during thermal exposure at a series of temperatures from 150 to 300℃ for 500 h.The results reveal that alloys A1 and A2 with an optimal Zn/Mg ratio(1.50-2.14)and relatively lower(Zn+Mg)content(7.0-8.8 wt.%),exhibit superior heat resistance properties compared to the other three alloys.Despite having lower strength relative to alloys with higher solute content,peak-aged alloys A1 and A2 retain the highest strength after thermal exposure.This performance is attributed to the high proportion(over 80%)of T'/T phases in the precipitates for alloys A1 and A2,which demonstrate better thermal stability in comparison to η'/η phases.Additionally,the lower solute content reduces the driving force for diffusion of Zn and Mg atoms,thus inhibiting the coarsening of precipitates.Moreover,the study elucidates that the coarsening mechanism of precipitates transitions from interfacial diffusion control at 150℃ to matrix diffusion control at 200-300℃.These insights into the composition-dependent coarsening behavior of precipitates in dual-phase strengthened Al-Zn-Mg-Cu alloys offer valuable guidance for designing heat-resistant aluminum alloys with enhanced performance at elevated temperatures.展开更多
The performance of Mg alloys is significantly influenced by the concentrations and solid solution behavior of the alloying elements.In this work,the solid solution behavior of 20 alloying elements in 190 ternary Mg al...The performance of Mg alloys is significantly influenced by the concentrations and solid solution behavior of the alloying elements.In this work,the solid solution behavior of 20 alloying elements in 190 ternary Mg alloy systems at 500℃are systematically investigated.The solid solution behavior of a set of two different alloying elements in Mg alloy systems are suggested to be classified into three categories:inclusivity,exclusivity and proportionality.Inclusivity classification indicates that the two alloying elements are inclusive inα-Mg,increasing the joint solubility of both elements.Exclusivity classification suggests that the two alloying elements have a low joint solid solubility inα-Mg,since they prefer to form stable second phases.For the proportionality classification,the solubility curve of the ternary Mg alloy systems is a straight line connecting the solubility points of the two sub-binary systems.The proposed classification theory was validated by key experiments and the calculation of formation energies.The interaction effects between alloying elements and the preference of formation of second phases are the main factors determining the solid solution behavior classifications.Based on the observed solid solution features of multi-component Mg alloys,principles for alloy design of different types of high-performance Mg alloys were proposed in this work.展开更多
文摘To investigate the influence of Al-Zn-Mg-Cu alloy with as-homogenized and as-rolled initial microstructures on the tensile flow behavior,isothermal tensile tests were conducted on a GLEEBLE-3500 isothermal simulator at temperatures of 380-440℃and strain rates of 0.05-1 s^(−1).The Johnson-Cook model,Hensel-Spittel model,strain-compensated Arrhenius model,and critical fracture strain model were established.Results show that through the evaluation of the models using the correlation coefficient(R)and the average absolute relative error,the strain-compensated Arrhenius model can represent the flow behavior of the alloy more accurately.Shear bands are more pronounced in the as-homogenized specimens,whereas dynamic recrystallization is predominantly observed in as-rolled specimens.Fracture morphology analysis reveals that a mixed fracture mechanism is prevalent in the as-homogenized specimen,whereas a ductile fracture mechanism is predominant in the as-rolled specimen.The processing maps indicate that the unstable region is reduced in the as-rolled specimens compared with that in the as-homogenized specimens.The optimal hot working windows for the as-homogenized and as-rolled specimens are determined as 410-440℃/0.14-1 s^(−1)and 380-400℃/0.05-0.29 s^(−1),respectively.
文摘Correction to:Nano-Micro Letters(2026)18:10.https://doi.org/10.1007/s40820-025-01852-8 Following publication of the original article[1],the authors reported that the last author’s name was inadvertently misspelled.The published version showed“Hongzhen Chen”,whereas the correct spelling should be“Hongzheng Chen”.The correct author name has been provided in this Correction,and the original article[1]has been corrected.
基金financially supported by the National Natural Science Foundation of China(Nos.52104319 and 52374323)。
文摘This study utilizes wet/dry cyclic corrosion testing combined with corrosion big data technology to investigate the mechanism by which chloride ions(Cl^(-))influence the corrosion behavior of 650 MPa high-strength low-alloy(HSLA)steel in industrially polluted environments.The corrosion process of 650 MPa HSLA steel occurred in two distinct stages:an initial corrosion stage and a stable corrosion stage.During the initial phase,the weight loss rate increased rapidly owing to the instability of the rust layer.Notably,this study demonstrated that 650 MPa HSLA steel exhibited superior corrosion resistance in Cl-containing environments.The formation of a corrosion-product film eventually reduced the weight-loss rate.However,the intrusion of Cl^(-)at increasing concentrations gradually destabilized theα/γ^(*)phases of the rust layer,leading to a looser structure and lower polarization resistance(R_(p)).The application of corrosion big data technology in this study facilitated the validation and analysis of the experimental results,offering new insights into the corrosion mechanisms of HSLA steel in chloride-rich environments.
基金supported by the National Natural Science Foundation of China(Grant No.42171135)the Science and Technology Program of CNOOC Research Institute(Grant No.2023OTKK03)the“CUG Scholar”Scientific Research Funds at China University of Geosciences(Project No.2022098).
文摘The volume change behavior of natural gas hydrate-bearing sediment is essential as it influences settlement,strength,and stiffness,which directly affect the stability of hydrate reservoirs during hydrate extraction or in response to environmental changes.The volume change is influenced not only by stress but also by the formation and dissociation of hydrates.This study adopted a customized apparatus for one-dimensional compression tests,allowing independent control of gas pressure and effective stress.Tests were conducted on samples with different hydrate saturations along various temperature-gas pressure-effective stress paths,yielding some conclusions related to compressibility and creep.An unusual phenomenon was observed under low-stress conditions:hydrate formation led to shrinkage rather than expansion.Three potential mechanisms behind this occurrence were discussed.As hydrate saturation increases,the yield stress rises while the compression and swelling indexes remain minimally affected.After hydrate dissociation,the compression curve of hydrate-bearing sediment drops to that of hydrate-free sediment.Once hydrate is formed,the compression curve of hydrate-free sediment gradually approaches that of hydrate-bearing sediment during the subsequent loading.Under low-stress conditions,the creep of both hydrate-free and hydrate-bearing sediments is very weak.However,when stress increases,significantly beyond the yield stress,the creep of both sediments increases significantly,with hydrate-bearing sediment exhibiting much greater creep than hydrate-free sediment.
基金support from the Joint Funds of the National Natural Science Foundation of China(Grant No.U23A2060)the National Natural Science Foundation of China(Grant Nos.42177143 and 52474150).
文摘Drilling and blasting tunneling is a cyclic process in which tunnel rock undergoes repeated blast loading,affecting its dynamic characteristics,energy evolution,and damage progression.To explore the dynamic mechanical properties and damage mechanisms of carbonaceous slate under cyclic impact loads of varying intensities,cyclic dynamic tests are conducted using a triaxial split Hopkinson pressure bar.This study analyzes the stress-strain relationship,energy damage evolution,and macro-to-micro failure characteristics.The results show that peak stress and strain are significantly influenced by impact intensity and the number of impacts.The initial dynamic stress is positively correlated with the impact intensity,but with more impact,the dynamic stress decreases while the peak strain increases.Energy evolution follows a pattern of"slow growthfluctuating growthrapid growth,"with the crack initiation stress and its proportion decreasing.CT and SEM analyses reveal that as the impact intensity increases,failure becomes more chaotic,the fracture volume increases,and the fracture mode shifts from interlayer and intergranular to through-layer and trans-granular fractures.These findings provide an experimental basis for soft rock tunnel stability analysis.
文摘BACKGROUND Despite societal guidelines recommending targeted screening for Barrett’s esophagus(BE)and esophageal adenocarcinoma(EAC)in individuals with gastroesophageal reflux symptoms(GERS),screening adherence is suboptimal.Current screening approaches fail to identify individuals not seeking medical consultation for GERS or whose GERS are managed with‘over-the-counter’(OTC)acid suppressant therapies.AIM To assess patients’self-management and help-seeking behavior for GERS.METHODS This cross-sectional study collected data from the Dutch general population aged 18-75 years between January and April 2023 using a web-based survey.The survey included questions regarding self-management(e.g.,use of acid suppressant therapy with or without prescription)and help-seeking behavior(e.g.,consulting a primary care provider)for GERS.Simple random sampling was performed to select individuals within the target age group.In total,18156 randomly selected individuals were invited to participate.The study protocol was registered in ClinicalTrials.gov(identifier:NCT05689918).RESULTS Of the 18156 invited individuals,3214 participants(17.7%)completed the survey,of which 1572 participants(48.9%)reported GERS.Of these,904 participants(57.5%)had never consulted a primary care provider for these symptoms,of which 331 participants(36.6%)reported taking OTC acid suppressant therapy in the past six months and 100 participants(11.1%)fulfilled the screening criteria for BE and EAC according to the European Society of Gastrointestinal Endoscopy Guideline.CONCLUSION The population fulfilling the screening criteria for BE and EAC is incompletely identified,suggesting potential underutilization of medical consultation.Raising public awareness of GERS as a risk factor for EAC is needed.
基金supported by the Spanish Ministry of Health‐Plan Nacional sobre Drogas(2023‐I024)the the Ministry of Science,Innovation and Universities/State ResearchAgency/10.13039/501100011033(PID2023-146865OB-I00)+2 种基金Generalitat Valenciana(CIAICO/2021/203)the Primary Addiction Care Research Network(RD21/0009/0005)FEDER Funds,GVA.
文摘Mesenchymal stem cell-derived extracellular vesicles have emerged as a promising form of regenerative and immunomodulatory therapy;indeed,micro(mi)RNAs contained within mesenchymal stem cell-derived extracellular vesicles modulate target gene expression and impact disease-associated pathways.Chronic alcohol consumption leads to neuroinflammation,brain damage,and impaired cognition.Evidence indicates that females are more vulnerable to alcohol-induced damage than males.While mesenchymal stem cell-derived extracellular vesicles have been studied in various neuroinflammatory conditions,their potential to counteract alcohol-induced brain damage remains unclear.In this study,we investigated whether repeated intravenous administration of mesenchymal stem cell-derived extracellular vesicles could ameliorate neuroinflammation and behavioral impairment induced by chronic alcohol consumption in female mice.Mesenchymal stem cell-derived extracellular vesicles diminished the increased binding of a micro-positron emission tomography tracer(^(18)F-FDG)when analyzing whole-brain 3D images and brain coronal sections of ethanol-treated mice.Mesenchymal stem cell-derived extracellular vesicle administration protected against ethanol-induced proinflammatory gene upregulation,cognitive dysfunction,and the conditioned rewarding effects of cocaine.MiRNA sequencing data from mesenchymal stem cell-derived extracellular vesicles revealed the elevated expression of extracellular vesicle-derived miR-483-5p and miR-140-3p in the brains of ethanol-treated female mice following mesenchymal stem cell-derived extracellular vesicle administration.In addition,mesenchymal stem cell-derived extracellular vesicles modulated the expression of pro-inflammatory-related miRNA target genes(e.g.,Socs3,Tnf,Mtor,and Atf6)in the brains of ethanol-treated female mice.These results suggest that mesenchymal stem cell-derived extracellular vesicles could function as a neuroprotective therapy to ameliorate the neuroinflammation,cognitive dysfunction,and conditioned rewarding effects of cocaine associated with chronic alcohol consumption.
文摘This paper prepared a novel as-cast W-Zr-Ti metallic ESM using high-frequency vacuum induction melting technique.The above ESM performs a typical elastic-brittle material feature and strain rate strengthening behavior.The specimens exhibit violent chemical reaction during the fracture process under the impact loading,and the size distribution of their residual debris follows Rosin-Rammler model.The dynamic fracture toughness is obtained by the fitting of debris length scale,approximately 1.87 MPa·m~(1/2).Microstructure observation on residual debris indicates that the failure process is determined by primary crack propagation under quasi-static compression,while it is affected by multiple cracks propagation in both particle and matrix in the case of dynamic impact.Impact test demonstrates that the novel energetic fragment performs brilliant penetration and combustion effect behind the front target,leading to the effective ignition of fuel tank.For the brittleness of as-cast W-ZrTi ESM,further study conducted bond-based peridynamic(BB-PD)C++computational code to simulate its fracture behavior during penetration.The BB-PD method successfully captured the fracture process and debris cloud formation of the energetic fragment.This paper explores a novel as-cast metallic ESM,and provides an available numerical avenue to the simulation of brittle energetic fragment.
文摘In the competitive retail industry of the digital era,data-driven insights into gender-specific customer behavior are essential.They support the optimization of store performance,layout design,product placement,and targeted marketing.However,existing computer vision solutions often rely on facial recognition to gather such insights,raising significant privacy and ethical concerns.To address these issues,this paper presents a privacypreserving customer analytics system through two key strategies.First,we deploy a deep learning framework using YOLOv9s,trained on the RCA-TVGender dataset.Cameras are positioned perpendicular to observation areas to reduce facial visibility while maintaining accurate gender classification.Second,we apply AES-128 encryption to customer position data,ensuring secure access and regulatory compliance.Our system achieved overall performance,with 81.5%mAP@50,77.7%precision,and 75.7%recall.Moreover,a 90-min observational study confirmed the system’s ability to generate privacy-protected heatmaps revealing distinct behavioral patterns between male and female customers.For instance,women spent more time in certain areas and showed interest in different products.These results confirm the system’s effectiveness in enabling personalized layout and marketing strategies without compromising privacy.
基金National Science and Technology Major Project(J2019-VI-0022-0138)。
文摘The high-cycle fatigue fracture characteristics and damage mechanism of nickel-based single crystal superalloys at 850℃ was investigated.The results indicate that high-cycle fatigue cracks in single crystal superalloys generally originate from defect locations on the subsurface or interior of the specimen at 850℃.Under the condition of stress ratio R=0.05,as the fatigue load decreases,the high-cycle fatigue life gradually increases.The high-cycle fatigue fracture is mainly characterized by octahedral slip mechanism.At high stress and low lifespan,the fracture exhibits single or multiple slip surface features.Some fractures originate along a vertical small plane and then propagate along the{111}slip surface.At low stress and high lifespan,the fracture surface tend to alternate and expand along multiple slip planes after originating from subsurface or internal sources,exhibiting characteristics of multiple slip planes.Through electron backscatter diffraction and transmission electron microscope analysis,there is obvious oxidation behavior on the surface of the high-cycle fatigue fracture,and the fracture section is composed of oxidation layer,distortion layer,and matrix layer from the outside to the inside.Among them,the main components of the oxidation layer are oxides of Ni and Co.The distortion layer is mainly distributed in the form of elongated or short rod-shaped oxides of Al,Ta,and W.The matrix layer is a single crystal layer.Crack initiation and propagation mechanism were obtained by systematical analysis of a large number of highcycle fatigue fractures.In addition,the stress ratio of 0.05 is closer to the vibration mode of turbine blades during actual service,providing effective guidance for the study of failure and fracture mechanisms of turbine blades.
文摘An energetic binder based on hydroxyl-terminated polybutadiene(HTPB),doped with different ratios of nitrocellulose(NC)(10%,20%,30%,and 50%),was developed to study the effect of NC doping on the thermal decomposition behavior of a composite propellant(CP)comprising ammonium nitrate(AN)as an oxidizer and magnesium(Mg)as a fuel.Optimization of the propellant formulation was conducted using Chemical Equilibrium with Applications-National Aeronautics and Space Administration(CEA-NASA)software,which demonstrated an increase in specific impulse by 12.09 s when the binder contained 50%NC.Fourier-transform infrared spectroscopy(FTIR)analysis confirmed the excellent compatibility between the components,and density measurements revealed an increase of 6.4%with a higher NC content.Morphological analysis using optical microscopy showed that NC doping improved the uniformity and compactness of the surface,reduced cavities,and achieved a more homogeneous particle distribution.Differential scanning calorimetry(DSC)analysis indicated a decrease in the decomposition temperature of the propellant as the NC content increased,while kinetic studies revealed a 48.68%reduction in the activation energy when 50%NC was incorporated into the binder.These findings suggest that the addition of NC enhances combustion efficiency and improves overall propellant performance.This study highlights the potential of the new HTPB-NC energetic binder as a promising approach for advancing solid propellant technology.
基金Key Project of Undergraduate Teaching Reform Research of Shandong Normal University(No.2024ZJ12)sixth batch of"Sports and Health"special topic of Education Research of Chinese Society of Education。
文摘Diabetes mellitus(DM)has become one of the most serious and common chronic diseases around the world,leading to various complications and a reduction in life expectancy.Increased sedentary behavior(SB)and decreased physical activity(PA)are important contributors to the rising prevalence of DM.This article reviews the research progress on the pathogenesis of DM,the effects of SB and PA on the risk of DM,aiming to explore the influence of different PA intensities,amounts,frequencies,durations and types on the incidence of DM.Research has shown that blood glucose levels tend to increase with the prolongation of SB.Within a certain range,PA intensity and PA amount are negatively correlated with the risk of DM;Performing PA for more than 3 days per week maintains normal glucose tolerance and lower blood pressure;Engaging in 150–300 min of moderate intensity exercise or 75–150 min of high-intensity exercise per week reduces the risk of DM;PA during leisure time reduces the risk of DM,while PA during work increases the risk of DM;Both aerobic training and resistance training reduce the risk of DM,and the combination of the two training methods produces better benefits;Various types of exercises,such as cycling,soccer,aerobics,yoga,tai chi,all reduce the risk of DM.In summary,prolonged SB increases the risk of DM,while appropriate PA reduces the risk of DM.As the intensity,amount,and frequency of PA increase,the effect of reducing DM risk becomes more significant.Different exercise methods have different effects on reducing DM risk.
基金financially supported by the National Science and Technology Major Project of China(No.2017-Ⅵ-0008-0078)。
文摘Four powder metallurgy(PM)Ni-based superalloys with different Hf and Ta contents were creep-tested at 650℃ and 970 MPa,700℃ and 770 MPa,and 750℃ and 580 MPa,respectively.The effect of Hf and Ta on creep deformation behaviors of the superalloys was studied from multiple scales by SEM,electron backscatter diffraction(EBSD),and aberration-corrected scanning transmission electron microscope(AC-STEM).The results showed that Hf and Ta suppressed the intergranular fracture and initiation of cracks during the acceleration creep stage,which prolonged the creep rupture time.Hf and Ta inhibited the stacking faults extending and the dislocation climbing and promoted the Suzuki segregation of W during the steady-state creep stage,which reduced the minimum creep rate and delayed the start time of the acceleration creep stage.The Suzuki segregation of Co,Cr,Mo,Ti,Nb,W,and Ta along stacking faults was observed after Hf and Ta addition,leading to the localized phase transformation in the γ′phase,and the stacking fault phase was chemically disordered.This study provided ideas for the composition design of novel PM Ni-based superalloys and theoretical foundations for the combined addition of Hf and Ta.
文摘Objective:This study aimed to examine the reliability and validity of the Chinese version of the Behavioral Inhibition System/Behavioral Activation System(BIS/BAS)scales among stroke survivors.Methods:The cross-sectional study was conducted at four comprehensive hospitals in Taizhou,Jiangsu,China.A sample of 232 first-ever stroke survivors were recruited from June to August 2023.Validity was examined using face validity and construct validity,which used confirmatory factor analysis(CFA)and known-group analysis.Reliability was evaluated by internal consistency and test-retest reliability.Results:The BIS/BAS scales demonstrated satisfactory face validity.The findings of CFAs supported the original four-factor structure of BAS-reward,BAS-drive,BAS-fun seeking,and BIS with acceptable model fit indices.Discriminative validity,assessed via known-group analysis,indicated that stroke survivors with probable depression had significantly lower mean BAS-reward,BAS-drive,and BAS-fun seeking scores(P<0.001)and a higher mean BIS score(P=0.028)compared to those without probable depression.The internal consistency,measured by Cronbach’s a coefficients for the subscales,ranged from 0.669 to 0.964.Test-retest reliability,assessed using intra-class correlation coefficients,ranged from 0.61 to 0.93.Conclusions:The Chinese version of the BIS/BAS scales could be a reliable and valid instrument for measuring behavioral activation among stroke survivors.
基金partially supported by the National Natural Science Foundation of China(No.51901153)Shanxi Scholarship Council of China(No.2019032)+1 种基金the Natural Science Foundation of Shanxi,China(No.202103021224049)the Shanxi Zhejiang University New Materials and Chemical Research Institute Scientific Research Project,China(No.2022SX-TD025)。
文摘A novel precipitate-free Mg-0.1Sn anode with a homogeneous equal-axis grain structure was developed and rolled successfully at 573 K.Electrochemical test results indicate that the Mg-0.1Sn alloy exhibits enhanced anode dissolution kinetics.A Mg-air battery prepared using this anode exhibits a cell voltage of 1.626 V at 0.5 mA/cm^(2),reasonable anodic efficiency of 58.17%,and good specific energy of 1730.96 mW·h/g at 10 mA/cm^(2).This performance is attributed to the effective reactive anode surface,the suppressed chunk effect,and weak self-corrosion owing to the homogeneous basal texture.
基金supported by ANID Fondecyt Iniciacion 11180540(to FJB)ANID PAI 77180077(to FJB)+2 种基金UNAB DI-02-22/REG(to FJB)Exploración-ANID 13220203(to FJB)ANID-MILENIO(NCN2023_23,to FJB)。
文摘Since the pioneering work by Broca and Wernicke in the 19th century,who examined individuals with brain lesions to associate them with specific behaviors,it was evident that behaviors are complex and cannot be fully attributable to specific brain areas alone.Instead,they involve connectivity among brain areas,whether close or distant.At that time,this approach was considered the optimal way to dissect brain circuitry and function.These pioneering efforts opened the field to explore the necessity or sufficiency of brain areas in controlling behavior and hence dissecting brain function.However,the connectivity of the brain and the mechanisms through which various brain regions regulate specific behaviors,either individually or collaboratively,remain largely elusive.Utilizing animal models,researchers have endeavored to unravel the necessity or sufficiency of specific brain areas in influencing behavior;however,no clear associations have been firmly established.
基金supported by the Guangdong Major Project of Basic and Applied Basic Research(Grant No.2020B0301030006).
文摘Magnesium matrix composites with both high strength and ductility have been achieved by introducing pure Ti particles.However,the properties of the surfaces of the composites need to be improved by surface technology,such as micro-arc oxidation(MAO).In this study,we investigated the influence of the Ti-reinforcement phase on coating growth and evolution by subjecting both AZ91 alloy and AZ91/Ti composite to MAO treatment using silicate-based and phosphate-based electrolytes.Results revealed that the Ti-reinforcement phase influenced the MAO process,altering discharge behavior,and leading to a decreased cell voltage.The vigorous discharge of the Ti-reinforcement phase induced the formation of coating discharge channels,concurrently dissolving and oxidizing Ti-reinforcement to produce a composite ceramic coating with TiO2.The MAO coating on the AZ91/Ti composite exhibited a dark blue macromorphology and distinctive local micromorphological anomalies.In silicate electrolyte,a“volcano-like”localized morphology centered on the discharge channel emerged.In contrast,treatment in phosphate-based electrolyte resulted in a coating morphology similar to typical porous ceramic coatings,with visible radial discharge micropores at the reinforcement phase location.Compared to the AZ91 alloy,the coating on the AZ91/Ti composite exhibited lower thickness and higher porosity.MAO treatment reduced the self-corrosion current density of the AZ91/Ti surface by two orders of magnitude.The silicate coating demonstrated better corrosion resistance than the phosphate coating,attributed to its lower porosity.The formation mechanism of MAO coatings on AZ91/Ti composites in phosphate-based and silicate-based electrolytes was proposed.
基金supported by the National Natural Science Foundation of China(Grant No.:82272749)the Natural Science Foundation of Liaoning Province,China(Grant No.:2022-MS-190).
文摘Mitochondria play a crucial role as organelles,managing several physiological processes such as redox balance,cell metabolism,and energy synthesis.Initially,the assumption was that mitochondria primarily resided in the host cells and could exclusively transmit from oocytes to offspring by a mechanism known as vertical inheritance of mitochondria.Recent scholarly works,however,suggest that certain cell types transmit their mitochondria to other developmental cell types via a mechanism referred to as intercellular or horizontal mitochondrial transfer.This review details the process of which mitochondria are transferred across cells and explains the impact of mitochondrial transfer between cells on the efficacy and functionality of cancer cells in various cancer forms.Specifically,we review the role of mitochondria transfer in regulating cellular metabolism restoration,excess reactive oxygen species(ROS)generation,proliferation,invasion,metastasis,mitophagy activation,mitochondrial DNA(mtDNA)inheritance,immune system modulation and therapeutic resistance in cancer.Additionally,we highlight the possibility of using intercellular mitochondria transfer as a therapeutic approach to treat cancer and enhance the efficacy of cancer treatments.
基金supported by the Natural Science Foundation of Chongqing(Nos.CSTB2022NSCQ-LZX0002 and CSTB2022NSCQ-BHX0624)the Chongqing Key Project for Technological Innovation and Application(No.CSTB2022TIAD-KPX0073)+1 种基金the Opening Project of State Key Laboratory for Advanced Metals and Materials(No.2022-Z03)the Science and Technology Research Program of Chongqing Municipal Education Commission(No.KJQN202200810).
文摘High-strength Al-Zn-Mg-Cu alloys are widely utilized,but their strength deteriorates as strengthening precipitates coarsen rapidly at elevated temperatures,limiting their applications above 150℃.This study systematically investigates the microstructure evolution and its impact on the properties of peak-aged Al-Zn-Mg-Cu alloys with varying Zn/Mg ratios during thermal exposure at a series of temperatures from 150 to 300℃ for 500 h.The results reveal that alloys A1 and A2 with an optimal Zn/Mg ratio(1.50-2.14)and relatively lower(Zn+Mg)content(7.0-8.8 wt.%),exhibit superior heat resistance properties compared to the other three alloys.Despite having lower strength relative to alloys with higher solute content,peak-aged alloys A1 and A2 retain the highest strength after thermal exposure.This performance is attributed to the high proportion(over 80%)of T'/T phases in the precipitates for alloys A1 and A2,which demonstrate better thermal stability in comparison to η'/η phases.Additionally,the lower solute content reduces the driving force for diffusion of Zn and Mg atoms,thus inhibiting the coarsening of precipitates.Moreover,the study elucidates that the coarsening mechanism of precipitates transitions from interfacial diffusion control at 150℃ to matrix diffusion control at 200-300℃.These insights into the composition-dependent coarsening behavior of precipitates in dual-phase strengthened Al-Zn-Mg-Cu alloys offer valuable guidance for designing heat-resistant aluminum alloys with enhanced performance at elevated temperatures.
基金financially supported by National Natural Science Foundation of China(grant numbers:52171100,U20A20234)National Key R&D Program of China(grant number:2021YFB3701100)。
文摘The performance of Mg alloys is significantly influenced by the concentrations and solid solution behavior of the alloying elements.In this work,the solid solution behavior of 20 alloying elements in 190 ternary Mg alloy systems at 500℃are systematically investigated.The solid solution behavior of a set of two different alloying elements in Mg alloy systems are suggested to be classified into three categories:inclusivity,exclusivity and proportionality.Inclusivity classification indicates that the two alloying elements are inclusive inα-Mg,increasing the joint solubility of both elements.Exclusivity classification suggests that the two alloying elements have a low joint solid solubility inα-Mg,since they prefer to form stable second phases.For the proportionality classification,the solubility curve of the ternary Mg alloy systems is a straight line connecting the solubility points of the two sub-binary systems.The proposed classification theory was validated by key experiments and the calculation of formation energies.The interaction effects between alloying elements and the preference of formation of second phases are the main factors determining the solid solution behavior classifications.Based on the observed solid solution features of multi-component Mg alloys,principles for alloy design of different types of high-performance Mg alloys were proposed in this work.
