Zn-ion hybrid supercapacitors(ZHSCs),as emerging energy storage systems,combine high energy and power density with cost-effectiveness and safety,attracting significant attention.However,due to the inherent energy stor...Zn-ion hybrid supercapacitors(ZHSCs),as emerging energy storage systems,combine high energy and power density with cost-effectiveness and safety,attracting significant attention.However,due to the inherent energy storage mechanism and the diminishing marginal benefits of increased porosity on capacitance,engineering porous nanostructures to develop carbon materials with ideal architectures is crucial for achieving high performance.Herein,a novel web-in-web porous carbon/carbon nanotubes(CNTs)composite has been proposed,fabricated by a simple phase separation method and two-step carbonization.During pre-oxidation,gradual air oxidation induces the formation of an O,N co-doped polymer-chain template,which subsequently transforms into a graphitized web during high-temperature carbonization.The optimized web-in-web structure,enriched with abundant active sites,accelerates mass transport and charge transfer kinetics.When assembled in ZHSCs,the web-in-web cathode achieved a high area capacitance(14,309 mF cm^(-2))with high mass loading(38.2 mg cm^(-2)).It delivered excellent high-rate performance at 50 mA cm^(-2)with a capacitance retention of 83%after 10,000 cycles,also boosting a high energy density(1452.7μWh cm^(-2))and power density(30.8 mW cm^(-2)).Furthermore,ex situ characterization and in situ electrochemical analyses reveal hybrid energy storage mechanisms,involving both physical/chemical adsorption and precipitation/dissolution across different potential regions.This study provides a promising strategy for designing high-area-capacitance carbon cathodes boosting high-performance ZHSCs.展开更多
Lithium/fluorinated carbon(Li/CF_(x))batteries are greatly limited in their applications mostly due to poor rate performances.In this study,N,P co-doped biomass carbon was synthesized using melamine and phytic acid as...Lithium/fluorinated carbon(Li/CF_(x))batteries are greatly limited in their applications mostly due to poor rate performances.In this study,N,P co-doped biomass carbon was synthesized using melamine and phytic acid as doping sources,and the resulting product was then utilized as a precursor for CF_(x).The resulting fluorinated biomass carbon has a high degree of fluorination,exceeding the specific capacity of commercial fluorinated graphite while also demonstrating exceptional performance at high discharge rates.During the fluorination process,N,P-containing functional groups were removed from the crystalline lattice in the basal plane.This facilitates the formation of a defect-rich carbon matrix,enhancing the F/C ratio by improving the fluorinated active sites and obtaining more highly active semi-ionic bonds.Additionally,the abundant defects and porous structure promote Li^(+)diffusion.Density functional theory calculations indicated that doping modification effectively reduces the energy barrier for Li+migration,enhancing Li+transport efficiency.The prepared CF_(x)delivers material with a maximum specific capacity of 919 mAh·g^(-1),while maintaining a specific capacity of 702 mAh·g^(-1)at a high discharge current density of 20C(with a capacity retention rate of 76.4%).In this study,fluorinated N,P co-doped biomass carbon,exhibiting ultrahigh capacity and high-rate performance,was prepared for the first time,which can potentially advance the commercialization of CF_(x).展开更多
To alleviate the main limitations of lithium ion diffusion rate and poor electronic conductivity for LiFePO4 cathode material, it is desirable to synthesize nano-size LiFePO4 material due to its enhanced electronic an...To alleviate the main limitations of lithium ion diffusion rate and poor electronic conductivity for LiFePO4 cathode material, it is desirable to synthesize nano-size LiFePO4 material due to its enhanced electronic and lithium ion transport rates and thus an improved high-rate performance. However, our previous synthesized LiFePO4 nanorods only exhibited low high-rate and slightly unstable cycle performance. Possible reasons are the poor crystallization and Fe2+ oxidation of LiFePO4 nanorods prepared by hydrothermal method. In this paper, LiFePO4 nanorods were simply dealt with at 700 ℃ for 4 h under the protection of Ar and H2 mixture gas. The electrochemical properties of LiFePO4/Li cells were investigated by galvanostatic test and cyclic voltammetry(CV). The experimental results indicated that the annealed LiFePO4 nanorods delivered an excellent cycling stability and obviously improved capacity of 150 mA·h·g-1 at 1C, and even 122 mA·h·g-1 at 5C.展开更多
The safe operating voltage and low volume variation of Li_(3)VO_(4)(LVO)make it an ideal anode material for lithium(Li)-ion batteries.However,the insufficient understanding of the inner storage mechanism hinders the d...The safe operating voltage and low volume variation of Li_(3)VO_(4)(LVO)make it an ideal anode material for lithium(Li)-ion batteries.However,the insufficient understanding of the inner storage mechanism hinders the design of LVO-based electrodes.Herein,we investigate,for the first time,the Li-ion storage activity in LVO via Cl doping.Moreover,N-doped C coating was simultaneously achieved in the Cl doping process,resulting in synergistically improved reaction kinetics.As a result,the as-prepared Cl-doped Li_(3)VO_(4) coated with N-doped C(Cl-LVO@NC)electrodes deliver a discharge capacity of 884.1 mAh/g after 200 cycles at 0.2 A/g,which is the highest among all of the LVO-based electrodes.The Cl-LVO@NC electrodes also exhibit high-capacity retention of 331.1 mAh/g at 8.0 A/g and full capacity recovery after 5 periods of rate testing over 400 cycles.After 5000 cycles at 4.0 A/g,the discharge capacity can be maintained at 423.2 mAh/g,which is superior to most LVO-based electrodes.The Li-ion storage activity in LVO via Cl doping and significant improvement in the high-rate Li-ion storage reported in this work can be used as references for the design of advanced LVO-based electrodes for high-power applications.展开更多
Co-free Li-rich Mn-based layered oxides are promising candidates for next-generation lithium-ion batteries(LIBs)due to their high specific capacity,high voltage,low cost.However,their commercialization is hindered by ...Co-free Li-rich Mn-based layered oxides are promising candidates for next-generation lithium-ion batteries(LIBs)due to their high specific capacity,high voltage,low cost.However,their commercialization is hindered by limited cycle life and poor rate performance.Herein,an in-situ simple and low-cost strategy with a nanoscale double-layer architecture of lithium polyphosphate(LiPP)and spinel phase covered on top of the bulk layered phase,is developed for Li_(1.2)Mn_(0.6)Ni_(0.2)O_(2)(LMNO)using Li^(+)-conductor LiPP(denoted as LMNO@S-LiPP).With such a double-layer covered architecture,the half-cell of LMNO@S-LiPP delivers an extremely high capacity of 202.5 mAh·g^(−1)at 1 A·g^(−1)and retains 85.3%of the initial capacity after 300 cycles,so far,the best highrate electrochemical performance of all the previously reported LMNOs.The energy density of the full-cell assembled with commercial graphite reaches 620.9 Wh·kg^(−1)(based on total weight of active materials in cathode and anode).Mechanism studies indicate that the superior electrochemical performance of LMNO@S-LiPP is originated from such a nanoscale double-layer covered architecture,which accelerates Li-ion diffusion,restrains oxygen release,inhibits interfacial side reactions,suppresses structural degradation during cycling.Moreover,this strategy is applicable for other high-energy-density cathodes,such as LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2),Li_(1.2)Ni_(0.13)Co_(0.13)Mn_(0.54)O_(2),LiCoO_(2).Hence,this work presents a simple,cost-effective,scalable strategy for the development of high-performance cathode materials.展开更多
With the rapid growth of technologies requiring high-power energy storage,achieving long-term cyclic stability under ultra-high current density is a key challenge.Aqueous zinc-ion batteries(AZIBs)are promising candida...With the rapid growth of technologies requiring high-power energy storage,achieving long-term cyclic stability under ultra-high current density is a key challenge.Aqueous zinc-ion batteries(AZIBs)are promising candidates due to their intrinsic safety and low cost,but they suffer from severe interfacial instability at rates exceeding 10 mA cm^(-2),which drastically shortens their cycle life.Inspired by theoretical calculations,triglyme(TGDE)additive with strong electron-donating groups into Zn(OTf)_(2) electrolytes effectively disrupts the hydrogen-bond network among free water molecules,while the weak coordination of TGDE with Zn^(2+)promotes the entry of OTf-into the primary Zn^(2+)solvated sheath,thus decreasing the coordination number of water with Zn^(2+).As such,the hydrogen-bond network and the bulk solvated structure are reconstructed with better stability.Moreover,the strong adsorption of TGDE lying on the Zn(002)surface would induce Zn depositions along(002)together with the reduced exposed surface,further effectively inhibiting side reactions.Likewise,TGDE electrolyte induces the formation of such ZnF_(2)-ZnS dual-layer solid electrolyte interface(SEI)with superior chemical stability and ionic conductivity,thereby regulating Zn^(2+)flux with dendrite-free depositions.Based on this electrolyte,Zn‖Zn cells can be stably cycled for 1300 h at a limit of 10 mA cm^(-2) and 10 mAh cm^(-2).The assembled Zn‖V_(2)O_(5) full cells still maintain 99.9%capacity retention after 1000 cycles at 10 A g^(-1).This work provides a feasible approach for designing aqueous electrolytes to reconstruct the hydrogen-bond network and solvated structure,which can be extended to the applications of high-rate and high-temperature scenarios.展开更多
Metal-organic framework(MOF)-derived porous carbon has attracted particular attention in the electrochemical energy storage field,of which the key is the design and preparation of electrode materials with adjustable p...Metal-organic framework(MOF)-derived porous carbon has attracted particular attention in the electrochemical energy storage field,of which the key is the design and preparation of electrode materials with adjustable porosity and defects for supercapacitors.Here,a novel strategy of coating ZIF-8 with coal tar pitch(CTP)is presented to tailor the porosity and defects of derived porous carbon,by which the inward contraction of ZIF-8 is prevented to enlarge the ultra-micropores,and the defects of ZIF-8-derived carbon are repaired to form a continuous conjugated network.The tradeoff between porosity and electrical conductivity endows this novel hard/soft carbon electrode with fast ion/electron diffusion,achieving high yet balanced capacitance and rate performance of a top-level specific area-normalized capacitance(40μF cm^(-2))and a capacitance retention of 52.1%at a 1000-fold increased current density.Meanwhile,the novel electrode realizes a high capacitance of 704 F g^(-1)at 1 A g^(-1)and capacitance retention of 91.9%after 50000 cycles in KOH+PPD electrolyte.This study provides an effective approach to designing novel hard/soft carbon with tuned porosity and carbon defects from MOFs and CTP for supercapacitors and other metal-ion batteries.展开更多
With the increasing application of lithium-ion batteries under high-rate operation,safety concerns such as thermal runaway(TR)and thermal runaway propagation(TRP)have become critical.In this study,the TRP action of ba...With the increasing application of lithium-ion batteries under high-rate operation,safety concerns such as thermal runaway(TR)and thermal runaway propagation(TRP)have become critical.In this study,the TRP action of batteries undergoing high-rate cycling is systematically investigated.Microanalysis results reveal that the crystallinity and I_((003))/I_((104))of the cathode are decreased by 32.95%and 13.01%after 4 C cycling,while the layered structure of the anode is seriously damaged.As revealed,the TR interval time(At)of batteries cycled at 4 C is decreased by 83.23%compared with that for batteries cycled at 1 C.Meanwhile,the maximum mass loss(ML)rate of Battery 2#is increased by 32.35%.We have further investigated the influence of battery spacing on TRP action.The maximum TR temperature of Battery2#at 1.5 cm spacing is reduced by 26.21%compared with the value at 0 cm spacing.When increasing the spacing from 0 to 1.5 cm,the ML of batteries is reduced by 20.73%.ML increases and decreases with the elevation of the charging rate and battery spacing,respectively.Compared with a battery cycled at1 C,a battery cycled at 4 C shows reduced heat required to trigger TR.The corresponding decreases can reach 68.28%,70.10%,76.88%,and 26.15%when setting the spacing at 0,0.6,1.5,and 2.1 cm,respectively.This indicates that Battery 2#can enter TR with much lower heat after high-rate cycling.Overall,high-rate cycling and low spacing accelerate the TRP of the battery and aggravate the TR severity of the battery.This work can provide insights for the practical safety design of energy storage systems.展开更多
The adsorptive denitrification performance of MIL-101(Cr)-0.5 toward pyridine,aniline or quinoline in simulated fuels with basic nitrogen content of 1732μg/g was evaluated separately.Furthermore,the effects of adsorp...The adsorptive denitrification performance of MIL-101(Cr)-0.5 toward pyridine,aniline or quinoline in simulated fuels with basic nitrogen content of 1732μg/g was evaluated separately.Furthermore,the effects of adsorption temperature,adsorption time and adsorbent dosage on their adsorptive denitrification performance were systematically investigated.The experimental results demonstrated that under a fixed adsorbent dosage of 0.05 g and a simulated fuel volume of 10 mL,the optimal removal efficiency for aniline was achieved at 30℃ within 30 min,whereas higher temperatures and longer times(40℃and 40 min)were required for effective removal of pyridine and quinoline.Density Functional Theory(DFT)calculations were conducted via Materials Studio(MS)software to study the adsorptive denitrification mechanism of MIL-101(Cr)toward these three basic nitrogen-containing compounds.The simulation calculation results revealed that the interaction between pyridine and MIL-101(Cr)primarily involved coordination adsorption.In contrast,the interaction between aniline or quinoline and MIL-101(Cr)proceeded mainly through coordination,with additional contributions fromπ-complexation and hydrogen bonding.The overall adsorption strength order is pyridine>aniline>quinoline.During the adsorption process,pyridine and quinoline transfer electrons to the MIL-101(Cr)surface through the H→C→N→Cr^(3+)pathway,while aniline transfers electrons to the MIL-101(Cr)surface through various pathways,including N→Cr^(3+),N→C→Cr^(3+)and N→H→O.Furthermore,adsorption kinetics studies indicated that the adsorption processes for all three basic nitrogen-containing compounds followed the quasi second order kinetic models.The experimental results on the effect of benzene on the adsorptive denitrification performance of MIL-101(Cr)-0.5 demonstrated that benzene exerted a more significant impact on the adsorption of aniline and quinoline.Finally,the adsorbent was regenerated using ethanol washing.It was found that MIL-101(Cr)-0.5 retained stable denitrification performance after two regeneration cycles.展开更多
Seismic intensity is critical for post-earthquake hazard assessment and response,but is often delayed because field surveys are required.Here,we propose a simple scheme for quick prediction of earthquake ground shakin...Seismic intensity is critical for post-earthquake hazard assessment and response,but is often delayed because field surveys are required.Here,we propose a simple scheme for quick prediction of earthquake ground shaking intensity using high-rate Global Navigation Satellite System(GNSS)data.In the scheme,high-rate GNSS displacement waveforms and static GNSS coseismic offsets are first used to invert the fault rupture process based on a one-fault model.The kinematic slip model is then employed as input for kinematic forward simulation to predict strong ground motion,which is subsequently convert into seismic intensities according to the China seismic intensity scale(GB/T 17742–2020).We take the 2021 Mw 7.3 Maduo Earthquake as a case study to illustrate the feasibility of this scheme.Our results show that the seismic intensity produced by the one-fault model is consistent with that from field investigations,especially in meizoseismal zones,suggesting that the scheme may serve as a potential solution for quick prediction of seismic intensity,which helps to disaster relief efforts after strong earthquakes.展开更多
To elucidate the effect of calcite-regulated activated carbon(AC)structure on low-temperature denitrification performance of SCR catalysts,this work prepared a series of Mn-Ce/De-AC-xCaCO_(3)(x is the calcite content ...To elucidate the effect of calcite-regulated activated carbon(AC)structure on low-temperature denitrification performance of SCR catalysts,this work prepared a series of Mn-Ce/De-AC-xCaCO_(3)(x is the calcite content in coal)catalysts were prepared by the incipient wetness impregnation method,followed by acid washing to remove calcium-containing minerals.Comprehensive characterization and low-temperature denitrification tests revealed that calcite-induced structural modulation of coal-derived AC significantly enhances catalytic activity.Specifically,NO conversion increased from 88.3%of Mn-Ce/De-AC to 91.7%of Mn-Ce/De-AC-1CaCO_(3)(210℃).The improved SCR denitrification activity results from the enhancement of physicochemical properties including higher Mn^(4+)content and Ce^(4+)/Ce^(3+)ratio,an abundance of chemisorbed oxygen and acidic sites,which could strengthen the SCR reaction pathways(richer NH_(3)activated species and bidentate nitrate active species).Therefore,NO removal is enhanced.展开更多
Severe failures of nonstructural components have occurred during previous earthquakes.Claddings are one of the most widely used nonstructural component and are installed in many modern buildings;therefore,an evaluatio...Severe failures of nonstructural components have occurred during previous earthquakes.Claddings are one of the most widely used nonstructural component and are installed in many modern buildings;therefore,an evaluation of their seismic performance is important and cannot be ignored.To investigate the seismic performance of large-sized high performance concrete cladding(HPCC),a series of full-scale experimental tests were conducted using a unidirectional shaking table.A steel supporting frame was used to install the HPCCs and reproduce the effects of the building under earthquake.The tests were divided into two parts:in-plane(IP)testing and out-plane(OP)testing.Three recorded accelerograms,one artificial accelerogram,and one sinusoidal accelerogram were used to conduct the shaking table tests.The results show that the maximum recorded IP responses of acceleration and interstory drift ratio were 1.04 g and 1/97,while the OP responses were 1.02 g and 1/51.The HPCCs functioned well throughout the entire experimental protocol.The fundamental frequency of the HPCCs systems rarely changed after the tests.展开更多
Purpose:ATLAS is a cross-sectional study aiming to investigate environmental and genetic determinants of athletic performance in healthy Greek competitive athletes(CA).This article presents the study design,investigat...Purpose:ATLAS is a cross-sectional study aiming to investigate environmental and genetic determinants of athletic performance in healthy Greek competitive athletes(CA).This article presents the study design,investigates the muscle strength performance(MSP)of 289 adult and teenage CA,exercisers,and physically inactive individuals(PI),and proposes predictive models of MSP for adults.Methods:Muscle maximal,speed,and explosive strength(MMS/MSS/MES)at unilateral maximal concentric flexion and extension contraction(FC/EC)were evaluated using Biodex System 3 PRO^(TM)at 60°/s,180°/s,and 300°/s,while additional performance markers were assessed through field ergometric testing.Participants were interviewed about their lifestyle,dietary habits,physical activity,injury,and medical history.Body composition was assessed via bioelectrical impedance.gDNA was extracted from biochemical samples and then genotyped.Statistical analysis was conducted using IBM SPSS Statistics v21.0 and R.Results:Age,fitness,and sex impacted correlations of MSP with body composition and anthropometric measurements(p<0.05).Among CA,females outperformed males in accuracy(p<0.001)while,males outperformed females in anaerobic power,MSP,speed,and endurance(p<0.001).Adult CA outperformed exercisers and PI in MMS,MSS,and MES(p<0.05).Multiple linear regression models,with predictors age,FFM,body extremity,training load explained the majority of variation in MMS(R^(2)_(adj):71.4%–88.9%),MSS(R^(2)_(adj):64.8%–78.4%),and MES(R^(2)_(adj):52.7%–68.4%)at EC,FC,and their mean(p<0.001).Conclusions:Muscle-strengthening strategies should be customized according to individual fitness levels,body composition,and anthropometric measurements.The innovative sex-specific regression models assessing MMS,MSS,and MES at EC and FC provide a framework for personalizing rehabilitation and skill-specific training strategies.展开更多
This study presents the development of high-performance,solvent-free polyurethane-urea(PU)elastomeric coatings engineered for rapid curing and precise sprayability.Utilizing polyoxytetramethylene glycol(PTMG)as the pr...This study presents the development of high-performance,solvent-free polyurethane-urea(PU)elastomeric coatings engineered for rapid curing and precise sprayability.Utilizing polyoxytetramethylene glycol(PTMG)as the primary polyol and a static-mixing spraying technique,the formulations were systematically optimized.It was found that a soft-segment content of 64% yields optimalmechanical properties,achieving a remarkable tensile strength exceeding 30 MPa.Crucially,the incorporation of an ultra-low concentration(0.002 wt%)of dibutyltin dilaurate catalyst was sufficient to enhance curing completeness and mechanical performance while effectively eliminating moisture-induced foaming,a common challenge in solvent-free spray applications.The gel and tack-free times were successfully reduced to the order of minutes through strategic formulation with the chain extender dimethylsulfidetoluene diamine,minimizing reliance on high catalyst loadings.Theresultant PTMG-based coatings exhibit exceptional comprehensive properties,including a tensile strength>30 MPa,elongation at break>400%,and a tear strength of 66 N/mm,significantly surpassing conventional polypropylene-diamine-based polyurea systems.Furthermore,the coatings demonstrated superior low-temperature flexibility,evidenced by a glass transition temperature of-53℃,and suppressed soft-segment crystallinity.The solvent-free nature and tunable curing kinetics of this system enable precise spraying on complex geometries,effectively overcoming thickness-control limitations for small-object applications.This work establishes a sustainable and high-performance coating solution ideal for demanding impact-and corrosionresistant protective layers.展开更多
The pursuit of symmetry has long shaped discussions in sports science,particularly in sprinting,where every fraction of a second counts.Yet,the human body is inherently asymmetrical–our hearts are slightly left,most ...The pursuit of symmetry has long shaped discussions in sports science,particularly in sprinting,where every fraction of a second counts.Yet,the human body is inherently asymmetrical–our hearts are slightly left,most favour one hand or foot,and limb lengths or joint flexibilities are rarely identical.This begs the question:Why do we insist that symmetry is essential for peak sprint performance?展开更多
Memristors have emerged as a transformative technology in the realm of electronic devices,offering unique advantages such as fast switching speeds,low power consumption,and the ability to sensor-memory-compute.The app...Memristors have emerged as a transformative technology in the realm of electronic devices,offering unique advantages such as fast switching speeds,low power consumption,and the ability to sensor-memory-compute.The applications span across non-volatile memory,neuromorphic computing,hardware security,and beyond,prompting memristors to become a versatile solution for next-generation computing and data storage systems.Despite enormous potential of memristors,the transition from laboratory prototypes to large-scale applications is challenging in terms of material stability,device reproducibility,and array scalability.This review systematically explores recent advancements in high-performance memristor technologies,focusing on performance enhancement strategies through material engineering,structural design,pulse protocol optimization,and algorithm control.We provide an in-depth analysis of key performance metrics tailored to specific applications,including non-volatile memory,neuromorphic computing,and hardware security.Furthermore,we propose a co-design framework that integrates device-level optimizations with operational-level improvements,aiming to bridge the gap between theoretical models and practical implementations.展开更多
In composite solid propellants with high aluminum(Al)content and low burning rate,incomplete combustion of the Al powder may occur.In this study,varying lithium(Li)content in Al-Li alloy powder was utilized instead of...In composite solid propellants with high aluminum(Al)content and low burning rate,incomplete combustion of the Al powder may occur.In this study,varying lithium(Li)content in Al-Li alloy powder was utilized instead of pure aluminum particles to mitigate agglomeration and enhance the combustion efficiency of solid propellants(Combustion efficiency herein refers to the completeness of metallic fuel oxidation,quantified as the ratio of actual-to-theoretical energy released during combustion)with high Al content and low burning rates.The impact of Al-Li alloy with different Li contents on combustion and agglomeration of solid propellant was investigated using explosion heat,combustion heat,differential thermal analysis(DTA),thermos-gravimetric analysis(TG),dynamic high-pressure combustion test,ignition experiment of small solid rocket motor(SRM)tests,condensation combustion product collection,and X-ray diffraction techniques(XRD).Compared with pure Al,Al-Li alloys exhibit higher combustion heat,which contributes to improved combustion efficiency in Al-Li alloy-containing propellants.DTA and TG analyses demonstrated higher reactivity and lower ignition temperatures for Al-Li alloys.High-pressure combustion experiments at 5 MPa showed that Al-Li alloy fuel significantly decreases combustion agglomeration.The results from theφ75 mm andφ165 mm SRM and XRD tests further support this finding.This study provides novel insights into the combustion and agglomeration behaviors of high-Al,low-burning-rate composite solid propellants and supports the potential application of Al-Li alloys in advanced propellant formulations.展开更多
The rapid advancements in computer vision(CV)technology have transformed the traditional approaches to material microstructure analysis.This review outlines the history of CV and explores the applications of deep-lear...The rapid advancements in computer vision(CV)technology have transformed the traditional approaches to material microstructure analysis.This review outlines the history of CV and explores the applications of deep-learning(DL)-driven CV in four key areas of materials science:microstructure-based performance prediction,microstructure information generation,microstructure defect detection,and crystal structure-based property prediction.The CV has significantly reduced the cost of traditional experimental methods used in material performance prediction.Moreover,recent progress made in generating microstructure images and detecting microstructural defects using CV has led to increased efficiency and reliability in material performance assessments.The DL-driven CV models can accelerate the design of new materials with optimized performance by integrating predictions based on both crystal and microstructural data,thereby allowing for the discovery and innovation of next-generation materials.Finally,the review provides insights into the rapid interdisciplinary developments in the field of materials science and future prospects.展开更多
In the era of materials genome engineering,data-driven machine learning has become a powerful tool for accelerating the re-search and development of metallic materials.However,the predictive accuracy and generalizatio...In the era of materials genome engineering,data-driven machine learning has become a powerful tool for accelerating the re-search and development of metallic materials.However,the predictive accuracy and generalization ability of traditional machine learning models are often limited by the scarcity and heterogeneity of available data,especially in small-sample scenarios.To address these chal-lenges,transfer learning has emerged as an effective strategy to leverage knowledge from related domains,thereby enhancing model per-formance with limited target data.This review systematically summarizes the fundamental concepts,methodologies,and representative applications of transfer learning in the prediction of metallic materials'properties.Transfer learning can be categorized into feature-based,instance-based,parameter-based,and knowledge-based methods.This work discusses their respective mechanisms,advantages,and limit-ations.Case studies demonstrate that transfer learning can significantly improve prediction accuracy,data efficiency,and model inter-pretability in tasks such as mechanical property prediction and alloy design.Furthermore,this work highlights emerging trends including hybrid,multi-task,meta,and adaptive transfer learning,which further expand the applicability of these techniques.Finally,this work out-lines future research directions,emphasizing the need for data standardization,algorithmic innovation,multimodal data fusion,and the in-tegration of physical principles to achieve robust,interpretable,and generalizable models.The perspectives presented aim to advance the intelligent design and discovery of metallic materials,promoting efficient knowledge transfer and collaborative innovation in materials science.展开更多
In the context of the revolution in new technologies,a key question is whether the rapid growth of the digital economy,driven by digital technologies,has improved regional innovation performance.Using inter-provincial...In the context of the revolution in new technologies,a key question is whether the rapid growth of the digital economy,driven by digital technologies,has improved regional innovation performance.Using inter-provincial panel data from China(2012–2022)and adopting a business environment perspective,this study applies a Panel Extended Regression Model(PERM),a Panel Simultaneous Equation Model(PSEM),and a Tobit-IV model to analyze how the development of the digital economy influences regional innovation.The results reveal a pronounced U-shaped relationship between the digital economy and the regional innovation performance at the provincial level in China,with the business environment serving as a significant mediator in this relationship.Moreover,regional innovation performance in China exhibits a“ratchet effect,”with the impact of the digital economy varying markedly across regions.While the eastern and western regions have entered an upward phase,whereby the digital economy boosts innovation,the central region displays a weaker effect.Further analysis indicates that the synergy between the business environment and the digital economy in driving innovation remains suboptimal.These findings were supported by robust checks.This study offers theoretical insights and empirical evidence that support the coordinated development of digital government and the digital factor market,as well as business environment reforms that are in alignment with the innovation demands of the digital era.展开更多
基金financially supported by the National Key Research and Development Program of China(No.2024YFA1210602)Guangdong Basic and Applied Basic Research Foundation(No.2023A1515140044)
文摘Zn-ion hybrid supercapacitors(ZHSCs),as emerging energy storage systems,combine high energy and power density with cost-effectiveness and safety,attracting significant attention.However,due to the inherent energy storage mechanism and the diminishing marginal benefits of increased porosity on capacitance,engineering porous nanostructures to develop carbon materials with ideal architectures is crucial for achieving high performance.Herein,a novel web-in-web porous carbon/carbon nanotubes(CNTs)composite has been proposed,fabricated by a simple phase separation method and two-step carbonization.During pre-oxidation,gradual air oxidation induces the formation of an O,N co-doped polymer-chain template,which subsequently transforms into a graphitized web during high-temperature carbonization.The optimized web-in-web structure,enriched with abundant active sites,accelerates mass transport and charge transfer kinetics.When assembled in ZHSCs,the web-in-web cathode achieved a high area capacitance(14,309 mF cm^(-2))with high mass loading(38.2 mg cm^(-2)).It delivered excellent high-rate performance at 50 mA cm^(-2)with a capacitance retention of 83%after 10,000 cycles,also boosting a high energy density(1452.7μWh cm^(-2))and power density(30.8 mW cm^(-2)).Furthermore,ex situ characterization and in situ electrochemical analyses reveal hybrid energy storage mechanisms,involving both physical/chemical adsorption and precipitation/dissolution across different potential regions.This study provides a promising strategy for designing high-area-capacitance carbon cathodes boosting high-performance ZHSCs.
基金supported by Fujian Science and Technology Planning Projects of China(Nos.2022T3067 and 2023H0045)the Self-deployment Project Research Programs of Haixi Institutes,Chinese Academy of Sciences(No.CXZX-2022-JQ12)the Self-deployment project of XIREM(No.2023GG02).
文摘Lithium/fluorinated carbon(Li/CF_(x))batteries are greatly limited in their applications mostly due to poor rate performances.In this study,N,P co-doped biomass carbon was synthesized using melamine and phytic acid as doping sources,and the resulting product was then utilized as a precursor for CF_(x).The resulting fluorinated biomass carbon has a high degree of fluorination,exceeding the specific capacity of commercial fluorinated graphite while also demonstrating exceptional performance at high discharge rates.During the fluorination process,N,P-containing functional groups were removed from the crystalline lattice in the basal plane.This facilitates the formation of a defect-rich carbon matrix,enhancing the F/C ratio by improving the fluorinated active sites and obtaining more highly active semi-ionic bonds.Additionally,the abundant defects and porous structure promote Li^(+)diffusion.Density functional theory calculations indicated that doping modification effectively reduces the energy barrier for Li+migration,enhancing Li+transport efficiency.The prepared CF_(x)delivers material with a maximum specific capacity of 919 mAh·g^(-1),while maintaining a specific capacity of 702 mAh·g^(-1)at a high discharge current density of 20C(with a capacity retention rate of 76.4%).In this study,fluorinated N,P co-doped biomass carbon,exhibiting ultrahigh capacity and high-rate performance,was prepared for the first time,which can potentially advance the commercialization of CF_(x).
基金Funded by the National Natural Science Foundation of China(51208396 and 21277017)the Fundamental Research Funds for the Central Universities(2013-Ia-36 and 2013-Ia-39)the Selfdetermined and Innovative Research Funds of WUT(136814016)
文摘To alleviate the main limitations of lithium ion diffusion rate and poor electronic conductivity for LiFePO4 cathode material, it is desirable to synthesize nano-size LiFePO4 material due to its enhanced electronic and lithium ion transport rates and thus an improved high-rate performance. However, our previous synthesized LiFePO4 nanorods only exhibited low high-rate and slightly unstable cycle performance. Possible reasons are the poor crystallization and Fe2+ oxidation of LiFePO4 nanorods prepared by hydrothermal method. In this paper, LiFePO4 nanorods were simply dealt with at 700 ℃ for 4 h under the protection of Ar and H2 mixture gas. The electrochemical properties of LiFePO4/Li cells were investigated by galvanostatic test and cyclic voltammetry(CV). The experimental results indicated that the annealed LiFePO4 nanorods delivered an excellent cycling stability and obviously improved capacity of 150 mA·h·g-1 at 1C, and even 122 mA·h·g-1 at 5C.
基金supported by the National Natural Science Foundation of China(No.52101262)Distinguished Youth Foundation of Hubei Province(2019CFA084)+1 种基金Educational offi ce of Hubei Province(Q20201201)the 111 project(D20015).
文摘The safe operating voltage and low volume variation of Li_(3)VO_(4)(LVO)make it an ideal anode material for lithium(Li)-ion batteries.However,the insufficient understanding of the inner storage mechanism hinders the design of LVO-based electrodes.Herein,we investigate,for the first time,the Li-ion storage activity in LVO via Cl doping.Moreover,N-doped C coating was simultaneously achieved in the Cl doping process,resulting in synergistically improved reaction kinetics.As a result,the as-prepared Cl-doped Li_(3)VO_(4) coated with N-doped C(Cl-LVO@NC)electrodes deliver a discharge capacity of 884.1 mAh/g after 200 cycles at 0.2 A/g,which is the highest among all of the LVO-based electrodes.The Cl-LVO@NC electrodes also exhibit high-capacity retention of 331.1 mAh/g at 8.0 A/g and full capacity recovery after 5 periods of rate testing over 400 cycles.After 5000 cycles at 4.0 A/g,the discharge capacity can be maintained at 423.2 mAh/g,which is superior to most LVO-based electrodes.The Li-ion storage activity in LVO via Cl doping and significant improvement in the high-rate Li-ion storage reported in this work can be used as references for the design of advanced LVO-based electrodes for high-power applications.
基金the financial support from the Ministry of Science and Technology of China(MoST,No.52090034)the Higher Education Discipline Innovation Project(No.B12015).
文摘Co-free Li-rich Mn-based layered oxides are promising candidates for next-generation lithium-ion batteries(LIBs)due to their high specific capacity,high voltage,low cost.However,their commercialization is hindered by limited cycle life and poor rate performance.Herein,an in-situ simple and low-cost strategy with a nanoscale double-layer architecture of lithium polyphosphate(LiPP)and spinel phase covered on top of the bulk layered phase,is developed for Li_(1.2)Mn_(0.6)Ni_(0.2)O_(2)(LMNO)using Li^(+)-conductor LiPP(denoted as LMNO@S-LiPP).With such a double-layer covered architecture,the half-cell of LMNO@S-LiPP delivers an extremely high capacity of 202.5 mAh·g^(−1)at 1 A·g^(−1)and retains 85.3%of the initial capacity after 300 cycles,so far,the best highrate electrochemical performance of all the previously reported LMNOs.The energy density of the full-cell assembled with commercial graphite reaches 620.9 Wh·kg^(−1)(based on total weight of active materials in cathode and anode).Mechanism studies indicate that the superior electrochemical performance of LMNO@S-LiPP is originated from such a nanoscale double-layer covered architecture,which accelerates Li-ion diffusion,restrains oxygen release,inhibits interfacial side reactions,suppresses structural degradation during cycling.Moreover,this strategy is applicable for other high-energy-density cathodes,such as LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2),Li_(1.2)Ni_(0.13)Co_(0.13)Mn_(0.54)O_(2),LiCoO_(2).Hence,this work presents a simple,cost-effective,scalable strategy for the development of high-performance cathode materials.
基金the financial support provided by the National Natural Science Foundation of China(grant no.22373032)the open research fund of Songshan Lake Materials Laboratory(grant no.2023SLABFK06)。
文摘With the rapid growth of technologies requiring high-power energy storage,achieving long-term cyclic stability under ultra-high current density is a key challenge.Aqueous zinc-ion batteries(AZIBs)are promising candidates due to their intrinsic safety and low cost,but they suffer from severe interfacial instability at rates exceeding 10 mA cm^(-2),which drastically shortens their cycle life.Inspired by theoretical calculations,triglyme(TGDE)additive with strong electron-donating groups into Zn(OTf)_(2) electrolytes effectively disrupts the hydrogen-bond network among free water molecules,while the weak coordination of TGDE with Zn^(2+)promotes the entry of OTf-into the primary Zn^(2+)solvated sheath,thus decreasing the coordination number of water with Zn^(2+).As such,the hydrogen-bond network and the bulk solvated structure are reconstructed with better stability.Moreover,the strong adsorption of TGDE lying on the Zn(002)surface would induce Zn depositions along(002)together with the reduced exposed surface,further effectively inhibiting side reactions.Likewise,TGDE electrolyte induces the formation of such ZnF_(2)-ZnS dual-layer solid electrolyte interface(SEI)with superior chemical stability and ionic conductivity,thereby regulating Zn^(2+)flux with dendrite-free depositions.Based on this electrolyte,Zn‖Zn cells can be stably cycled for 1300 h at a limit of 10 mA cm^(-2) and 10 mAh cm^(-2).The assembled Zn‖V_(2)O_(5) full cells still maintain 99.9%capacity retention after 1000 cycles at 10 A g^(-1).This work provides a feasible approach for designing aqueous electrolytes to reconstruct the hydrogen-bond network and solvated structure,which can be extended to the applications of high-rate and high-temperature scenarios.
基金funded by the National Natural Science Foundation of China (No. 52372037)the Natural Science Foundation of Anhui Province (Nos. 2408085MB032)+1 种基金the Outstanding Scientific Research and Innovation Team Program of Higher Education Institutions of Anhui Province (No. 2023AH010015)support from the Anhui International Research Center of Energy Materials Green Manufacturing and Biotechnology
文摘Metal-organic framework(MOF)-derived porous carbon has attracted particular attention in the electrochemical energy storage field,of which the key is the design and preparation of electrode materials with adjustable porosity and defects for supercapacitors.Here,a novel strategy of coating ZIF-8 with coal tar pitch(CTP)is presented to tailor the porosity and defects of derived porous carbon,by which the inward contraction of ZIF-8 is prevented to enlarge the ultra-micropores,and the defects of ZIF-8-derived carbon are repaired to form a continuous conjugated network.The tradeoff between porosity and electrical conductivity endows this novel hard/soft carbon electrode with fast ion/electron diffusion,achieving high yet balanced capacitance and rate performance of a top-level specific area-normalized capacitance(40μF cm^(-2))and a capacitance retention of 52.1%at a 1000-fold increased current density.Meanwhile,the novel electrode realizes a high capacitance of 704 F g^(-1)at 1 A g^(-1)and capacitance retention of 91.9%after 50000 cycles in KOH+PPD electrolyte.This study provides an effective approach to designing novel hard/soft carbon with tuned porosity and carbon defects from MOFs and CTP for supercapacitors and other metal-ion batteries.
基金supported by the National Key Research and Development Plan(2023YFC30099000)the National Natural Science Foundation of China(52104197,52272396,52474233)+2 种基金the Major Basic Research Project of the Natural Science Foundation of the Jiangsu Higher Education Institutions(2020240521)the Open Fund of the State Key Laboratory of Fire Science(SKLFS)Program(HZ2025-KF03)the Postgraduate Research&Practice Innovation Program of Jiangsu Province(SJCX25_0595)。
文摘With the increasing application of lithium-ion batteries under high-rate operation,safety concerns such as thermal runaway(TR)and thermal runaway propagation(TRP)have become critical.In this study,the TRP action of batteries undergoing high-rate cycling is systematically investigated.Microanalysis results reveal that the crystallinity and I_((003))/I_((104))of the cathode are decreased by 32.95%and 13.01%after 4 C cycling,while the layered structure of the anode is seriously damaged.As revealed,the TR interval time(At)of batteries cycled at 4 C is decreased by 83.23%compared with that for batteries cycled at 1 C.Meanwhile,the maximum mass loss(ML)rate of Battery 2#is increased by 32.35%.We have further investigated the influence of battery spacing on TRP action.The maximum TR temperature of Battery2#at 1.5 cm spacing is reduced by 26.21%compared with the value at 0 cm spacing.When increasing the spacing from 0 to 1.5 cm,the ML of batteries is reduced by 20.73%.ML increases and decreases with the elevation of the charging rate and battery spacing,respectively.Compared with a battery cycled at1 C,a battery cycled at 4 C shows reduced heat required to trigger TR.The corresponding decreases can reach 68.28%,70.10%,76.88%,and 26.15%when setting the spacing at 0,0.6,1.5,and 2.1 cm,respectively.This indicates that Battery 2#can enter TR with much lower heat after high-rate cycling.Overall,high-rate cycling and low spacing accelerate the TRP of the battery and aggravate the TR severity of the battery.This work can provide insights for the practical safety design of energy storage systems.
基金Supported by Basic Scientific Research Project of the Liaoning Provincial Department of Education Has Been Unveiled to Facilitate Local Project Funding (JYTMS20230835)Enhanced Scientific Research Project Funded by the Departmentof Higher Education in Liaoning Province (General program)(JYTMS20230852)。
文摘The adsorptive denitrification performance of MIL-101(Cr)-0.5 toward pyridine,aniline or quinoline in simulated fuels with basic nitrogen content of 1732μg/g was evaluated separately.Furthermore,the effects of adsorption temperature,adsorption time and adsorbent dosage on their adsorptive denitrification performance were systematically investigated.The experimental results demonstrated that under a fixed adsorbent dosage of 0.05 g and a simulated fuel volume of 10 mL,the optimal removal efficiency for aniline was achieved at 30℃ within 30 min,whereas higher temperatures and longer times(40℃and 40 min)were required for effective removal of pyridine and quinoline.Density Functional Theory(DFT)calculations were conducted via Materials Studio(MS)software to study the adsorptive denitrification mechanism of MIL-101(Cr)toward these three basic nitrogen-containing compounds.The simulation calculation results revealed that the interaction between pyridine and MIL-101(Cr)primarily involved coordination adsorption.In contrast,the interaction between aniline or quinoline and MIL-101(Cr)proceeded mainly through coordination,with additional contributions fromπ-complexation and hydrogen bonding.The overall adsorption strength order is pyridine>aniline>quinoline.During the adsorption process,pyridine and quinoline transfer electrons to the MIL-101(Cr)surface through the H→C→N→Cr^(3+)pathway,while aniline transfers electrons to the MIL-101(Cr)surface through various pathways,including N→Cr^(3+),N→C→Cr^(3+)and N→H→O.Furthermore,adsorption kinetics studies indicated that the adsorption processes for all three basic nitrogen-containing compounds followed the quasi second order kinetic models.The experimental results on the effect of benzene on the adsorptive denitrification performance of MIL-101(Cr)-0.5 demonstrated that benzene exerted a more significant impact on the adsorption of aniline and quinoline.Finally,the adsorbent was regenerated using ethanol washing.It was found that MIL-101(Cr)-0.5 retained stable denitrification performance after two regeneration cycles.
基金supported by the Basic Scientific Funding of the Institute of Geology,China Earthquake Administration(No.IGCEA2120)the National Natural Science Foundation of China(Nos.U2139202 and 42104007)the Innovation Fund Project for College Teachers of Gansu Provincial Education Department(No.2025A-041)。
文摘Seismic intensity is critical for post-earthquake hazard assessment and response,but is often delayed because field surveys are required.Here,we propose a simple scheme for quick prediction of earthquake ground shaking intensity using high-rate Global Navigation Satellite System(GNSS)data.In the scheme,high-rate GNSS displacement waveforms and static GNSS coseismic offsets are first used to invert the fault rupture process based on a one-fault model.The kinematic slip model is then employed as input for kinematic forward simulation to predict strong ground motion,which is subsequently convert into seismic intensities according to the China seismic intensity scale(GB/T 17742–2020).We take the 2021 Mw 7.3 Maduo Earthquake as a case study to illustrate the feasibility of this scheme.Our results show that the seismic intensity produced by the one-fault model is consistent with that from field investigations,especially in meizoseismal zones,suggesting that the scheme may serve as a potential solution for quick prediction of seismic intensity,which helps to disaster relief efforts after strong earthquakes.
基金Supported by the Science and Technology Cooperation and Exchange special project of Cooperation of Shanxi Province(202404041101014)the Fundamental Research Program of Shanxi Province(202403021212333)+3 种基金the Joint Funds of the National Natural Science Foundation of China(U24A20555)the Lvliang Key R&D of University-Local Cooperation(2023XDHZ10)the Initiation Fund for Doctoral Research of Taiyuan University of Science and Technology(20242026)the Outstanding Doctor Funding Award of Shanxi Province(20242080).
文摘To elucidate the effect of calcite-regulated activated carbon(AC)structure on low-temperature denitrification performance of SCR catalysts,this work prepared a series of Mn-Ce/De-AC-xCaCO_(3)(x is the calcite content in coal)catalysts were prepared by the incipient wetness impregnation method,followed by acid washing to remove calcium-containing minerals.Comprehensive characterization and low-temperature denitrification tests revealed that calcite-induced structural modulation of coal-derived AC significantly enhances catalytic activity.Specifically,NO conversion increased from 88.3%of Mn-Ce/De-AC to 91.7%of Mn-Ce/De-AC-1CaCO_(3)(210℃).The improved SCR denitrification activity results from the enhancement of physicochemical properties including higher Mn^(4+)content and Ce^(4+)/Ce^(3+)ratio,an abundance of chemisorbed oxygen and acidic sites,which could strengthen the SCR reaction pathways(richer NH_(3)activated species and bidentate nitrate active species).Therefore,NO removal is enhanced.
基金National Key R&D Program of China under Grant No.2024YFD1600404。
文摘Severe failures of nonstructural components have occurred during previous earthquakes.Claddings are one of the most widely used nonstructural component and are installed in many modern buildings;therefore,an evaluation of their seismic performance is important and cannot be ignored.To investigate the seismic performance of large-sized high performance concrete cladding(HPCC),a series of full-scale experimental tests were conducted using a unidirectional shaking table.A steel supporting frame was used to install the HPCCs and reproduce the effects of the building under earthquake.The tests were divided into two parts:in-plane(IP)testing and out-plane(OP)testing.Three recorded accelerograms,one artificial accelerogram,and one sinusoidal accelerogram were used to conduct the shaking table tests.The results show that the maximum recorded IP responses of acceleration and interstory drift ratio were 1.04 g and 1/97,while the OP responses were 1.02 g and 1/51.The HPCCs functioned well throughout the entire experimental protocol.The fundamental frequency of the HPCCs systems rarely changed after the tests.
文摘Purpose:ATLAS is a cross-sectional study aiming to investigate environmental and genetic determinants of athletic performance in healthy Greek competitive athletes(CA).This article presents the study design,investigates the muscle strength performance(MSP)of 289 adult and teenage CA,exercisers,and physically inactive individuals(PI),and proposes predictive models of MSP for adults.Methods:Muscle maximal,speed,and explosive strength(MMS/MSS/MES)at unilateral maximal concentric flexion and extension contraction(FC/EC)were evaluated using Biodex System 3 PRO^(TM)at 60°/s,180°/s,and 300°/s,while additional performance markers were assessed through field ergometric testing.Participants were interviewed about their lifestyle,dietary habits,physical activity,injury,and medical history.Body composition was assessed via bioelectrical impedance.gDNA was extracted from biochemical samples and then genotyped.Statistical analysis was conducted using IBM SPSS Statistics v21.0 and R.Results:Age,fitness,and sex impacted correlations of MSP with body composition and anthropometric measurements(p<0.05).Among CA,females outperformed males in accuracy(p<0.001)while,males outperformed females in anaerobic power,MSP,speed,and endurance(p<0.001).Adult CA outperformed exercisers and PI in MMS,MSS,and MES(p<0.05).Multiple linear regression models,with predictors age,FFM,body extremity,training load explained the majority of variation in MMS(R^(2)_(adj):71.4%–88.9%),MSS(R^(2)_(adj):64.8%–78.4%),and MES(R^(2)_(adj):52.7%–68.4%)at EC,FC,and their mean(p<0.001).Conclusions:Muscle-strengthening strategies should be customized according to individual fitness levels,body composition,and anthropometric measurements.The innovative sex-specific regression models assessing MMS,MSS,and MES at EC and FC provide a framework for personalizing rehabilitation and skill-specific training strategies.
基金funded by the National Natural Science Foundation of China(No.U2330207)the presidential foundation of China Academy of Engineering Physics(No.YZJJZQ2024004).
文摘This study presents the development of high-performance,solvent-free polyurethane-urea(PU)elastomeric coatings engineered for rapid curing and precise sprayability.Utilizing polyoxytetramethylene glycol(PTMG)as the primary polyol and a static-mixing spraying technique,the formulations were systematically optimized.It was found that a soft-segment content of 64% yields optimalmechanical properties,achieving a remarkable tensile strength exceeding 30 MPa.Crucially,the incorporation of an ultra-low concentration(0.002 wt%)of dibutyltin dilaurate catalyst was sufficient to enhance curing completeness and mechanical performance while effectively eliminating moisture-induced foaming,a common challenge in solvent-free spray applications.The gel and tack-free times were successfully reduced to the order of minutes through strategic formulation with the chain extender dimethylsulfidetoluene diamine,minimizing reliance on high catalyst loadings.Theresultant PTMG-based coatings exhibit exceptional comprehensive properties,including a tensile strength>30 MPa,elongation at break>400%,and a tear strength of 66 N/mm,significantly surpassing conventional polypropylene-diamine-based polyurea systems.Furthermore,the coatings demonstrated superior low-temperature flexibility,evidenced by a glass transition temperature of-53℃,and suppressed soft-segment crystallinity.The solvent-free nature and tunable curing kinetics of this system enable precise spraying on complex geometries,effectively overcoming thickness-control limitations for small-object applications.This work establishes a sustainable and high-performance coating solution ideal for demanding impact-and corrosionresistant protective layers.
文摘The pursuit of symmetry has long shaped discussions in sports science,particularly in sprinting,where every fraction of a second counts.Yet,the human body is inherently asymmetrical–our hearts are slightly left,most favour one hand or foot,and limb lengths or joint flexibilities are rarely identical.This begs the question:Why do we insist that symmetry is essential for peak sprint performance?
基金supported by the National Key R&D Project from the Minister of Science and Technology(2024YFA1211500)the National Natural Science Foundation of China(Grant Nos.62304130,62405158 and 62574123)+1 种基金the Shanghai youth science and technology star project(24QA2702800)Shanghai Key Laboratory of Chips and Systems for Intelligent Connected Vehicle。
文摘Memristors have emerged as a transformative technology in the realm of electronic devices,offering unique advantages such as fast switching speeds,low power consumption,and the ability to sensor-memory-compute.The applications span across non-volatile memory,neuromorphic computing,hardware security,and beyond,prompting memristors to become a versatile solution for next-generation computing and data storage systems.Despite enormous potential of memristors,the transition from laboratory prototypes to large-scale applications is challenging in terms of material stability,device reproducibility,and array scalability.This review systematically explores recent advancements in high-performance memristor technologies,focusing on performance enhancement strategies through material engineering,structural design,pulse protocol optimization,and algorithm control.We provide an in-depth analysis of key performance metrics tailored to specific applications,including non-volatile memory,neuromorphic computing,and hardware security.Furthermore,we propose a co-design framework that integrates device-level optimizations with operational-level improvements,aiming to bridge the gap between theoretical models and practical implementations.
基金the National Natural Science Foundation of China(Grant No.U2441263)for financial support of this work。
文摘In composite solid propellants with high aluminum(Al)content and low burning rate,incomplete combustion of the Al powder may occur.In this study,varying lithium(Li)content in Al-Li alloy powder was utilized instead of pure aluminum particles to mitigate agglomeration and enhance the combustion efficiency of solid propellants(Combustion efficiency herein refers to the completeness of metallic fuel oxidation,quantified as the ratio of actual-to-theoretical energy released during combustion)with high Al content and low burning rates.The impact of Al-Li alloy with different Li contents on combustion and agglomeration of solid propellant was investigated using explosion heat,combustion heat,differential thermal analysis(DTA),thermos-gravimetric analysis(TG),dynamic high-pressure combustion test,ignition experiment of small solid rocket motor(SRM)tests,condensation combustion product collection,and X-ray diffraction techniques(XRD).Compared with pure Al,Al-Li alloys exhibit higher combustion heat,which contributes to improved combustion efficiency in Al-Li alloy-containing propellants.DTA and TG analyses demonstrated higher reactivity and lower ignition temperatures for Al-Li alloys.High-pressure combustion experiments at 5 MPa showed that Al-Li alloy fuel significantly decreases combustion agglomeration.The results from theφ75 mm andφ165 mm SRM and XRD tests further support this finding.This study provides novel insights into the combustion and agglomeration behaviors of high-Al,low-burning-rate composite solid propellants and supports the potential application of Al-Li alloys in advanced propellant formulations.
基金financially supported by the National Science Fund for Distinguished Young Scholars,China(No.52025041)the National Natural Science Foundation of China(Nos.52450003,U2341267,and 52174294)+1 种基金the National Postdoctoral Program for Innovative Talents,China(No.BX20240437)the Fundamental Research Funds for the Central Universities,China(Nos.FRF-IDRY-23-037 and FRF-TP-20-02C2)。
文摘The rapid advancements in computer vision(CV)technology have transformed the traditional approaches to material microstructure analysis.This review outlines the history of CV and explores the applications of deep-learning(DL)-driven CV in four key areas of materials science:microstructure-based performance prediction,microstructure information generation,microstructure defect detection,and crystal structure-based property prediction.The CV has significantly reduced the cost of traditional experimental methods used in material performance prediction.Moreover,recent progress made in generating microstructure images and detecting microstructural defects using CV has led to increased efficiency and reliability in material performance assessments.The DL-driven CV models can accelerate the design of new materials with optimized performance by integrating predictions based on both crystal and microstructural data,thereby allowing for the discovery and innovation of next-generation materials.Finally,the review provides insights into the rapid interdisciplinary developments in the field of materials science and future prospects.
基金supported by the National NaturalScience Foundation of China(Nos.52301029 and 52274359)the Fundamental Research Funds for the CentralUniversities,China(No.06500165)+2 种基金the Guangdong Basicand Applied Basic Research Foundation,China(No.2022A1515140006)Young Elite Scientists Sponsorship Program by CAST(No.2023QNRC001)Beijing Young Elite Scientists Sponsorship Program by BMES,China.
文摘In the era of materials genome engineering,data-driven machine learning has become a powerful tool for accelerating the re-search and development of metallic materials.However,the predictive accuracy and generalization ability of traditional machine learning models are often limited by the scarcity and heterogeneity of available data,especially in small-sample scenarios.To address these chal-lenges,transfer learning has emerged as an effective strategy to leverage knowledge from related domains,thereby enhancing model per-formance with limited target data.This review systematically summarizes the fundamental concepts,methodologies,and representative applications of transfer learning in the prediction of metallic materials'properties.Transfer learning can be categorized into feature-based,instance-based,parameter-based,and knowledge-based methods.This work discusses their respective mechanisms,advantages,and limit-ations.Case studies demonstrate that transfer learning can significantly improve prediction accuracy,data efficiency,and model inter-pretability in tasks such as mechanical property prediction and alloy design.Furthermore,this work highlights emerging trends including hybrid,multi-task,meta,and adaptive transfer learning,which further expand the applicability of these techniques.Finally,this work out-lines future research directions,emphasizing the need for data standardization,algorithmic innovation,multimodal data fusion,and the in-tegration of physical principles to achieve robust,interpretable,and generalizable models.The perspectives presented aim to advance the intelligent design and discovery of metallic materials,promoting efficient knowledge transfer and collaborative innovation in materials science.
基金National Social Science Fund of China(18KXS009)the Sichuan Provincial Soft Science Program(22JDR0261)the Sichuan University“From 0 to 1”Innovation Research Program(2021CXC10)。
文摘In the context of the revolution in new technologies,a key question is whether the rapid growth of the digital economy,driven by digital technologies,has improved regional innovation performance.Using inter-provincial panel data from China(2012–2022)and adopting a business environment perspective,this study applies a Panel Extended Regression Model(PERM),a Panel Simultaneous Equation Model(PSEM),and a Tobit-IV model to analyze how the development of the digital economy influences regional innovation.The results reveal a pronounced U-shaped relationship between the digital economy and the regional innovation performance at the provincial level in China,with the business environment serving as a significant mediator in this relationship.Moreover,regional innovation performance in China exhibits a“ratchet effect,”with the impact of the digital economy varying markedly across regions.While the eastern and western regions have entered an upward phase,whereby the digital economy boosts innovation,the central region displays a weaker effect.Further analysis indicates that the synergy between the business environment and the digital economy in driving innovation remains suboptimal.These findings were supported by robust checks.This study offers theoretical insights and empirical evidence that support the coordinated development of digital government and the digital factor market,as well as business environment reforms that are in alignment with the innovation demands of the digital era.