As carrier aircraft sortie frequency and flight deck operational density increase,autonomous dispatch trajectory planning for carrier-based vehicles demands efficient,safe,and kinematically feasible solutions.This pap...As carrier aircraft sortie frequency and flight deck operational density increase,autonomous dispatch trajectory planning for carrier-based vehicles demands efficient,safe,and kinematically feasible solutions.This paper presents an Iterative Safe Dispatch Corridor(iSDC)framework,addressing the suboptimality of the traditional SDC method caused by static corridor construction and redundant obstacle exploration.First,a Kinodynamic-Informed-Bidirectional Rapidly-exploring Random Tree Star(KIBRRT^(*))algorithm is proposed for the front-end coarse planning.By integrating bidirectional tree expansion,goal-biased elliptical sampling,and artificial potential field guidance,it reduces unnecessary exploration near concave obstacles and generates kinematically admissible paths.Secondly,the traditional SDC is implemented in an iterative manner,and the obtained trajectory in the current iteration is fed into the next iteration for corridor generation,thus progressively improving the quality of withincorridor constraints.For tractors,a reverse-motion penalty function is incorporated into the back-end optimizer to prioritize forward driving,aligning with mechanical constraints and human operational preferences.Numerical validations on the data of Gerald R.Ford-class carrier demonstrate that the KIBRRT^(*)reduces average computational time by 75%and expansion nodes by 25%compared to conventional RRT^(*)algorithms.Meanwhile,the iSDC framework yields more time-efficient trajectories for both carrier aircraft and tractors,with the dispatch time reduced by 31.3%and tractor reverse motion proportion decreased by 23.4%relative to traditional SDC.The presented framework offers a scalable solution for autonomous dispatch in confined and safety-critical environment,and an illustrative animation is available at bilibili.com/video/BV1tZ7Zz6Eyz.Moreover,the framework can be easily extended to three-dimension scenarios,and thus applicable for trajectory planning of aerial and underwater vehicles.展开更多
This study investigates in-station pressure drop mechanisms in a shale gas gathering system,providing a quantitative basis for flow system optimization.Computational fluid dynamics(CFD)simulations,based on field-measu...This study investigates in-station pressure drop mechanisms in a shale gas gathering system,providing a quantitative basis for flow system optimization.Computational fluid dynamics(CFD)simulations,based on field-measured parameters related to a representative case(a shale gas platform located in Sichuan,China)are conducted to analyze the flow characteristics of specific fittings and manifolds,and to quantify fitting resistance coefficients and manifold inlet interference.The resulting coefficients are integrated into a full-station gathering network model in PipeSim,which,combined with production data,enables evaluation of pressure losses and identification of equivalent pipeline blockages.The results indicate that the resistance coefficients,valid only for fittings under the studied field-specific geometries,are 0.21 for 90◦elbows in the fully open position,0.16 for gate valve passages in the fully open position,and 2.3 for globe valve passages.Manifold interference decreases with lower high-pressure inlet values,whereas inlets farther from the high-pressure side experience stronger disturbances.Interestingly,significant discrepancies between simulated and measured pressure drops reveal partial blockages,corresponding to effective diameter reductions of 65 mm,38 mm,44 mm,38 mm,and 28 mm for Wells 1#,3#,5#,and 6#,respectively.展开更多
Terahertz biotechnology has been increasingly applied in various biomedical fields and has especially shown great potential for application in brain sciences.In this article,we review the development of terahertz biot...Terahertz biotechnology has been increasingly applied in various biomedical fields and has especially shown great potential for application in brain sciences.In this article,we review the development of terahertz biotechnology and its applications in the field of neuropsychiatry.Available evidence indicates promising prospects for the use of terahertz spectroscopy and terahertz imaging techniques in the diagnosis of amyloid disease,cerebrovascular disease,glioma,psychiatric disease,traumatic brain injury,and myelin deficit.In vitro and animal experiments have also demonstrated the potential therapeutic value of terahertz technology in some neuropsychiatric diseases.Although the precise underlying mechanism of the interactions between terahertz electromagnetic waves and the biosystem is not yet fully understood,the research progress in this field shows great potential for biomedical noninvasive diagnostic and therapeutic applications.However,the biosafety of terahertz radiation requires further exploration regarding its two-sided efficacy in practical applications.This review demonstrates that terahertz biotechnology has the potential to be a promising method in the field of neuropsychiatry based on its unique advantages.展开更多
This study investigated the effect of konjac glucomannan(KGM)on the flotation separation of calcite and scheelite.Micro-flotation tests showed that under the action of 50 mg/L KGM,the floatability of calcite notably d...This study investigated the effect of konjac glucomannan(KGM)on the flotation separation of calcite and scheelite.Micro-flotation tests showed that under the action of 50 mg/L KGM,the floatability of calcite notably decreased,while the impact on scheelite was negligible,resulting in a recovery difference of 82.53%.Fourier transform infrared(FTIR)spectroscopy and atomic force micro-scopy(AFM)analyses indicated the selective adsorption of KGM on the calcite surface.Test results of the zeta potential and UV-visible absorption spectroscopy revealed that KGM prevented the adsorption of sodium oleate on the calcite surface.X-ray photoelectron spec-troscopy(XPS)analysis further confirmed the chemical adsorption of KGM on the calcite surface and the formation of Ca(OH)_(2).The density functional theory(DFT)simulation results were consistent with the flotation tests,demonstrating the strong adsorption perform-ance of KGM on the calcite surface.This study offers a pathway for highly sustainable and cost-effective mineral processing by utilizing the unique properties of biopolymers such as KGM to separate valuable minerals from gangue minerals.展开更多
When a perpendicular magnetic field penetrates a thin slab of a type-Ⅱ superconductor it produces vortices,with one vortex per flux quantum,h/2e.The vortices interact repulsively and form an ordered array(Abrikosov l...When a perpendicular magnetic field penetrates a thin slab of a type-Ⅱ superconductor it produces vortices,with one vortex per flux quantum,h/2e.The vortices interact repulsively and form an ordered array(Abrikosov lattice)in clean systems,while strong disorder changes the lattice into a vortex glass.The collective vortex dynamics is extremely vulnerable to external perturbations.Consequently,although of great importance,experimental observation is limited.Here we investigate type-Ⅱ superconducting films(PdBi_(2)and NbSe_(2))with surface acoustic waves(SAWs)at mK temperature.When sweeping the magnetic field at an extremely slow rate,we observe a series of spikes in the attenuation and velocity of the SAW,on average separated in field by approximately Hc1.We propose the following scenario:The vortex-free region at the edges of the film produces an edge barrier across which the vortices can enter or leave.When the applied field changes,the induced supercurrents flowing along this edge region lowers this barrier until there is an instability.At that point,vortices avalanche into(or out of)the bulk and change the vortex crystal,suggested by the sharp jump in each such spike.The vortices then gradually relax to a new stable pinned configuration,leading to a~30 s relaxation after the jump.Our observation enriches the limited experimental evidence on the important topic of real-time vortex dynamics in superconductors.展开更多
A promising way to realize controlled nuclear fusion involves the use of magnetic fields to control and confine the hot plasma configuration.This approach requires superconductor magnets operating above 15 T for the n...A promising way to realize controlled nuclear fusion involves the use of magnetic fields to control and confine the hot plasma configuration.This approach requires superconductor magnets operating above 15 T for the next generation of fusion devices.Due to their high in-field transport current capacity,rare-Earth barium copper oxide(REBCO)coated conductors are promising materials for manufacturing of cable-in-conduit conductors(CICCs)for fusion.However,the high-aspect-ratio geometry makes it difficult to find a multi-tape CICC configuration that fulfills the high engineering current density requirements while retaining enough flexibility for winding large-scale magnets.Moreover,the multilayer structure and inherent brittleness make the REBCO tapes susceptible to degradation during CICC manufacturing and operation.For more than a decade,the development of a reliable REBCO-based CICC that can sustain the huge combined mechanical,thermal,and Lorentz loads without degradation has been ongoing,albeit with limited progress.In this paper,we report on a prototype REBCO CICC that can withstand an applied cyclic Lorentz load of at least 830 kN·m^(-1),corresponding to a transport current of 80 kA at 10.85 T and 4.5 K.To our knowledge,this is the highest load achieved to date.The CICC uses 288 tapes wound into six strengthened sub-cables,making it capable of having a current sharing temperature,Tcs,of around 39 and 20 K when operated under 10.85 T with a current of 40 and 80 kA,respectively.Scaled to a 20-T peak field and 46.5-kA transport current,this provides a temperature margin of over 10 K with respect to an operating temperature of 4.5 K.In addition,no perceptible transport current performance degradation was observed after cyclic Lorentz loading,cyclic warm-up/cool-down(WUCD),and quench campaigns.The proposed REBCO CICC is a milestone in the development of high-temperature superconductors for large-scale and high-field magnet applications.展开更多
Grassland degradation presents overwhelming challenges to biodiversity,ecosystem services,and the socioeconomic sustainability of dependent communities.However,a comprehensive synthesis of global knowledge on the fron...Grassland degradation presents overwhelming challenges to biodiversity,ecosystem services,and the socioeconomic sustainability of dependent communities.However,a comprehensive synthesis of global knowledge on the frontiers and key areas of grassland degradation research has not been achieved due to the limitations of traditional scientometrics methods.The present synthesis of information employed BERTopic,an advanced natural language processing tool,to analyze the extensive ecological literature on grassland degradation.We compiled a dataset of 4,504 publications from the Web of Science core collection database and used it to evaluate the geographic distribution and temporal evolution of different grassland types and available knowledge on the subject.Our analysis identified key topics in the global grassland degradation research domain,including the effects of grassland degradation on ecosystem functions,grassland ecological restoration and biodiversity conservation,erosion processes and hydrological models in grasslands,and others.The BERTopic analysis significantly outperforms traditional methods in identifying complex and evolving topics in large datasets of literature.Compared to traditional scientometrics analysis,BERTopic provides a more comprehensive perspective on the research areas,revealing not only popular topics but also emerging research areas that traditional methods may overlook,although scientometrics offers more specificity and detail.Therefore,we argue for the simultaneous use of both approaches to achieve more systematic and comprehensive assessments of specific research areas.This study represents an emerging application of BERTopic algorithms in ecological research,particularly in the critical research focused on global grassland degradation.It also highlights the need for integrating advanced computational methods in ecological research in this era of data explosion.Tools like the BERTopic algorithm are essential for enhancing our understanding of complex environmental problems,and it marks an important stride towards more sophisticated,data-driven analysis in ecology.展开更多
Molecular dynamics(MD)simulation is employed to investigate the deformation behavior under various loading paths and strain rates of nanocrystalline magnesium(NC Mg)with[0001]texture.Atomic-scale structural evolution ...Molecular dynamics(MD)simulation is employed to investigate the deformation behavior under various loading paths and strain rates of nanocrystalline magnesium(NC Mg)with[0001]texture.Atomic-scale structural evolution of NC Mg was performed under uniaxial and biaxial loadings.In tension process,compression twins and basal slip dominate,while the compression process is dominated by tension twins.The activation mechanism of twinning is highly sensitive to the loading path and grain orientation.Meanwhile,the effect of strain rate on the structural evolution of NC Mg was investigated.It is found that the effect of strain rate on the plastic deformation of NC Mg is reflected through the plasticity delays and the way to release the stress.As the strain rate decreases,the plastic deformation mechanism gradually changes from intragranular to grain boundary.Some significant potential deformation mechanisms in the loading process were studied.It is observed that{1121}twins nucleated inside the grains,and the thickening process is completed by basal〈a〉slip of the twin boundary.The strain compatibility between twins is automatically optimized with loading.Moreover,the detwinning mechanism caused by the interaction between twins and basal stacking faults is clarified.展开更多
Lithium-sulfur(Li–S)battery has become one of the most promising next-generation electrical storage systems because of its exceptional energy density of 2600 Wh kg1.However,their commercialization is hindered by seve...Lithium-sulfur(Li–S)battery has become one of the most promising next-generation electrical storage systems because of its exceptional energy density of 2600 Wh kg1.However,their commercialization is hindered by several key obstacles,notably the polysulfide shuttle effect,poor electrical conductance of sulfur,and considerable volumetric change during cycling.This review addresses current advancements in microstructural innovations aimed at improving Li–S battery performance,focusing on modifying cathode materials.The strategies discussed primarily revolve around enhancing the conductivity of sulfur and effectively confining polysulfides to reduce the dissolving of lithium polysulfides in organic electrolytes.Key findings highlight the effectiveness of porous carbon structures and metal compounds in stabilizing polysulfides and enhancing electrochemical performances.Additionally,the roles of advanced synthesis techniques that facilitate the creation of hybrid cathodes with superior mechanical properties and cycling stability are summarized.By addressing the inherent limitations of traditional Li–S battery designs,these innovations pave the way for more efficient and reliable energy storage systems,positioning Li–S technology as a viable alternative to conventional lithium-ion batteries in future applications.展开更多
基金support of the National Key Research and Development Plan(Grant No.2021YFB3302501)the financial support of the National Science Foundation of China(Grant No.12161076)the financial support of the Fundamental Research Funds for the Central Universities(Grant No.DUT24LAB129).
文摘As carrier aircraft sortie frequency and flight deck operational density increase,autonomous dispatch trajectory planning for carrier-based vehicles demands efficient,safe,and kinematically feasible solutions.This paper presents an Iterative Safe Dispatch Corridor(iSDC)framework,addressing the suboptimality of the traditional SDC method caused by static corridor construction and redundant obstacle exploration.First,a Kinodynamic-Informed-Bidirectional Rapidly-exploring Random Tree Star(KIBRRT^(*))algorithm is proposed for the front-end coarse planning.By integrating bidirectional tree expansion,goal-biased elliptical sampling,and artificial potential field guidance,it reduces unnecessary exploration near concave obstacles and generates kinematically admissible paths.Secondly,the traditional SDC is implemented in an iterative manner,and the obtained trajectory in the current iteration is fed into the next iteration for corridor generation,thus progressively improving the quality of withincorridor constraints.For tractors,a reverse-motion penalty function is incorporated into the back-end optimizer to prioritize forward driving,aligning with mechanical constraints and human operational preferences.Numerical validations on the data of Gerald R.Ford-class carrier demonstrate that the KIBRRT^(*)reduces average computational time by 75%and expansion nodes by 25%compared to conventional RRT^(*)algorithms.Meanwhile,the iSDC framework yields more time-efficient trajectories for both carrier aircraft and tractors,with the dispatch time reduced by 31.3%and tractor reverse motion proportion decreased by 23.4%relative to traditional SDC.The presented framework offers a scalable solution for autonomous dispatch in confined and safety-critical environment,and an illustrative animation is available at bilibili.com/video/BV1tZ7Zz6Eyz.Moreover,the framework can be easily extended to three-dimension scenarios,and thus applicable for trajectory planning of aerial and underwater vehicles.
基金the National Natural Science Foundation of China under Grant 52441411,52325402 and 52274057Deep Earth Probe and Mineral Resources Exploration-National Science and Technology Major Project under Grant 2024ZD1004302-04the National Key R&D Program of China under Grant 2023YFB4104200.
文摘This study investigates in-station pressure drop mechanisms in a shale gas gathering system,providing a quantitative basis for flow system optimization.Computational fluid dynamics(CFD)simulations,based on field-measured parameters related to a representative case(a shale gas platform located in Sichuan,China)are conducted to analyze the flow characteristics of specific fittings and manifolds,and to quantify fitting resistance coefficients and manifold inlet interference.The resulting coefficients are integrated into a full-station gathering network model in PipeSim,which,combined with production data,enables evaluation of pressure losses and identification of equivalent pipeline blockages.The results indicate that the resistance coefficients,valid only for fittings under the studied field-specific geometries,are 0.21 for 90◦elbows in the fully open position,0.16 for gate valve passages in the fully open position,and 2.3 for globe valve passages.Manifold interference decreases with lower high-pressure inlet values,whereas inlets farther from the high-pressure side experience stronger disturbances.Interestingly,significant discrepancies between simulated and measured pressure drops reveal partial blockages,corresponding to effective diameter reductions of 65 mm,38 mm,44 mm,38 mm,and 28 mm for Wells 1#,3#,5#,and 6#,respectively.
基金supported by grants from the National Key R&D Program of China,No.2017YFC0909200(to DC)the National Natural Science Foundation of China,No.62075225(to HZ)+1 种基金Zhejiang Provincial Medical Health Science and Technology Project,No.2023XY053(to ZP)Zhejiang Provincial Traditional Chinese Medical Science and Technology Project,No.2023ZL703(to ZP).
文摘Terahertz biotechnology has been increasingly applied in various biomedical fields and has especially shown great potential for application in brain sciences.In this article,we review the development of terahertz biotechnology and its applications in the field of neuropsychiatry.Available evidence indicates promising prospects for the use of terahertz spectroscopy and terahertz imaging techniques in the diagnosis of amyloid disease,cerebrovascular disease,glioma,psychiatric disease,traumatic brain injury,and myelin deficit.In vitro and animal experiments have also demonstrated the potential therapeutic value of terahertz technology in some neuropsychiatric diseases.Although the precise underlying mechanism of the interactions between terahertz electromagnetic waves and the biosystem is not yet fully understood,the research progress in this field shows great potential for biomedical noninvasive diagnostic and therapeutic applications.However,the biosafety of terahertz radiation requires further exploration regarding its two-sided efficacy in practical applications.This review demonstrates that terahertz biotechnology has the potential to be a promising method in the field of neuropsychiatry based on its unique advantages.
基金supported by the National Natural Science Foundation of China(No.52164022).
文摘This study investigated the effect of konjac glucomannan(KGM)on the flotation separation of calcite and scheelite.Micro-flotation tests showed that under the action of 50 mg/L KGM,the floatability of calcite notably decreased,while the impact on scheelite was negligible,resulting in a recovery difference of 82.53%.Fourier transform infrared(FTIR)spectroscopy and atomic force micro-scopy(AFM)analyses indicated the selective adsorption of KGM on the calcite surface.Test results of the zeta potential and UV-visible absorption spectroscopy revealed that KGM prevented the adsorption of sodium oleate on the calcite surface.X-ray photoelectron spec-troscopy(XPS)analysis further confirmed the chemical adsorption of KGM on the calcite surface and the formation of Ca(OH)_(2).The density functional theory(DFT)simulation results were consistent with the flotation tests,demonstrating the strong adsorption perform-ance of KGM on the calcite surface.This study offers a pathway for highly sustainable and cost-effective mineral processing by utilizing the unique properties of biopolymers such as KGM to separate valuable minerals from gangue minerals.
基金supported by the National Key Research Program of China(Grant Nos.2021YFA1401900,2022YFA1403300,and 2020YFA0309100)the Innovation Program for Quantum Science and Technology(Grant Nos.2021ZD0302602 and 2024ZD0300103)+1 种基金the National Natural Science Foundation of China(Grant No.12074073)for samplefabrication and measurementthe support by the The Basic Research Program of the Chinese Academy of Sciences Based on Major Scientific Infrastructures(Grant No.JZHKYPT-2021-08).
文摘When a perpendicular magnetic field penetrates a thin slab of a type-Ⅱ superconductor it produces vortices,with one vortex per flux quantum,h/2e.The vortices interact repulsively and form an ordered array(Abrikosov lattice)in clean systems,while strong disorder changes the lattice into a vortex glass.The collective vortex dynamics is extremely vulnerable to external perturbations.Consequently,although of great importance,experimental observation is limited.Here we investigate type-Ⅱ superconducting films(PdBi_(2)and NbSe_(2))with surface acoustic waves(SAWs)at mK temperature.When sweeping the magnetic field at an extremely slow rate,we observe a series of spikes in the attenuation and velocity of the SAW,on average separated in field by approximately Hc1.We propose the following scenario:The vortex-free region at the edges of the film produces an edge barrier across which the vortices can enter or leave.When the applied field changes,the induced supercurrents flowing along this edge region lowers this barrier until there is an instability.At that point,vortices avalanche into(or out of)the bulk and change the vortex crystal,suggested by the sharp jump in each such spike.The vortices then gradually relax to a new stable pinned configuration,leading to a~30 s relaxation after the jump.Our observation enriches the limited experimental evidence on the important topic of real-time vortex dynamics in superconductors.
基金supported by the Comprehensive Research Facility for the Fusion Technology Program of China(2018-000052-73-01-001228)the National Key Research and Development Program of China(2022YFE03150200)+3 种基金the Institute of Energy,Hefei Comprehensive National Science Center(21KZS207)the National Natural Science Foundation of China(52077212)the Youth Innovation Promotion Association of the Chinese Academy of Sciences(2021444)the European–China collaboration program on the FUSION magnet.
文摘A promising way to realize controlled nuclear fusion involves the use of magnetic fields to control and confine the hot plasma configuration.This approach requires superconductor magnets operating above 15 T for the next generation of fusion devices.Due to their high in-field transport current capacity,rare-Earth barium copper oxide(REBCO)coated conductors are promising materials for manufacturing of cable-in-conduit conductors(CICCs)for fusion.However,the high-aspect-ratio geometry makes it difficult to find a multi-tape CICC configuration that fulfills the high engineering current density requirements while retaining enough flexibility for winding large-scale magnets.Moreover,the multilayer structure and inherent brittleness make the REBCO tapes susceptible to degradation during CICC manufacturing and operation.For more than a decade,the development of a reliable REBCO-based CICC that can sustain the huge combined mechanical,thermal,and Lorentz loads without degradation has been ongoing,albeit with limited progress.In this paper,we report on a prototype REBCO CICC that can withstand an applied cyclic Lorentz load of at least 830 kN·m^(-1),corresponding to a transport current of 80 kA at 10.85 T and 4.5 K.To our knowledge,this is the highest load achieved to date.The CICC uses 288 tapes wound into six strengthened sub-cables,making it capable of having a current sharing temperature,Tcs,of around 39 and 20 K when operated under 10.85 T with a current of 40 and 80 kA,respectively.Scaled to a 20-T peak field and 46.5-kA transport current,this provides a temperature margin of over 10 K with respect to an operating temperature of 4.5 K.In addition,no perceptible transport current performance degradation was observed after cyclic Lorentz loading,cyclic warm-up/cool-down(WUCD),and quench campaigns.The proposed REBCO CICC is a milestone in the development of high-temperature superconductors for large-scale and high-field magnet applications.
基金financially supported by the First-Class Curriculum Program at the School of Economics and Management,University of the Chinese Academy of Sciencesthe National Natural Science Foundation of China(42041005)the National Social Science Foundation of China(23BTQ054)。
文摘Grassland degradation presents overwhelming challenges to biodiversity,ecosystem services,and the socioeconomic sustainability of dependent communities.However,a comprehensive synthesis of global knowledge on the frontiers and key areas of grassland degradation research has not been achieved due to the limitations of traditional scientometrics methods.The present synthesis of information employed BERTopic,an advanced natural language processing tool,to analyze the extensive ecological literature on grassland degradation.We compiled a dataset of 4,504 publications from the Web of Science core collection database and used it to evaluate the geographic distribution and temporal evolution of different grassland types and available knowledge on the subject.Our analysis identified key topics in the global grassland degradation research domain,including the effects of grassland degradation on ecosystem functions,grassland ecological restoration and biodiversity conservation,erosion processes and hydrological models in grasslands,and others.The BERTopic analysis significantly outperforms traditional methods in identifying complex and evolving topics in large datasets of literature.Compared to traditional scientometrics analysis,BERTopic provides a more comprehensive perspective on the research areas,revealing not only popular topics but also emerging research areas that traditional methods may overlook,although scientometrics offers more specificity and detail.Therefore,we argue for the simultaneous use of both approaches to achieve more systematic and comprehensive assessments of specific research areas.This study represents an emerging application of BERTopic algorithms in ecological research,particularly in the critical research focused on global grassland degradation.It also highlights the need for integrating advanced computational methods in ecological research in this era of data explosion.Tools like the BERTopic algorithm are essential for enhancing our understanding of complex environmental problems,and it marks an important stride towards more sophisticated,data-driven analysis in ecology.
基金supports from the projects by the NSFC[51771166]the Hebei Natural Science Foundation[E2019203452,E2021203011]+3 种基金the key project of department of education of Hebei province[ZD2021107]project of the central government guiding local science and technology development[216Z1001G]Cultivation Project for Basic Research and Innovation of Yanshan University[2021LGZD002]project of State Key Laboratory of Materials Processing and Die&Mould Technology[P2023-004]are gratefully acknowledged.
文摘Molecular dynamics(MD)simulation is employed to investigate the deformation behavior under various loading paths and strain rates of nanocrystalline magnesium(NC Mg)with[0001]texture.Atomic-scale structural evolution of NC Mg was performed under uniaxial and biaxial loadings.In tension process,compression twins and basal slip dominate,while the compression process is dominated by tension twins.The activation mechanism of twinning is highly sensitive to the loading path and grain orientation.Meanwhile,the effect of strain rate on the structural evolution of NC Mg was investigated.It is found that the effect of strain rate on the plastic deformation of NC Mg is reflected through the plasticity delays and the way to release the stress.As the strain rate decreases,the plastic deformation mechanism gradually changes from intragranular to grain boundary.Some significant potential deformation mechanisms in the loading process were studied.It is observed that{1121}twins nucleated inside the grains,and the thickening process is completed by basal〈a〉slip of the twin boundary.The strain compatibility between twins is automatically optimized with loading.Moreover,the detwinning mechanism caused by the interaction between twins and basal stacking faults is clarified.
基金Songshan Lake Materials Laboratory(2022SLABFN26)National Natural Science Foundation of China(21773024).
文摘Lithium-sulfur(Li–S)battery has become one of the most promising next-generation electrical storage systems because of its exceptional energy density of 2600 Wh kg1.However,their commercialization is hindered by several key obstacles,notably the polysulfide shuttle effect,poor electrical conductance of sulfur,and considerable volumetric change during cycling.This review addresses current advancements in microstructural innovations aimed at improving Li–S battery performance,focusing on modifying cathode materials.The strategies discussed primarily revolve around enhancing the conductivity of sulfur and effectively confining polysulfides to reduce the dissolving of lithium polysulfides in organic electrolytes.Key findings highlight the effectiveness of porous carbon structures and metal compounds in stabilizing polysulfides and enhancing electrochemical performances.Additionally,the roles of advanced synthesis techniques that facilitate the creation of hybrid cathodes with superior mechanical properties and cycling stability are summarized.By addressing the inherent limitations of traditional Li–S battery designs,these innovations pave the way for more efficient and reliable energy storage systems,positioning Li–S technology as a viable alternative to conventional lithium-ion batteries in future applications.
