Nature|大型汉族人群队列助力中国台湾精准医疗精准医学的发展依赖于大规模、具有深度表型和基因变异图谱数据的人群队列,然而这在非欧洲人群中数据仍严重不足。中国台湾精准医学计划(Taiwan Precision Medicine Initiative,TPMI)旨在...Nature|大型汉族人群队列助力中国台湾精准医疗精准医学的发展依赖于大规模、具有深度表型和基因变异图谱数据的人群队列,然而这在非欧洲人群中数据仍严重不足。中国台湾精准医学计划(Taiwan Precision Medicine Initiative,TPMI)旨在建立一个具有广泛代表性的中国台湾汉族人群队列,以支持大规模基因组与健康医学研究(2025年10月15日在线发表,doi:10.1038/s41586-025-09680-x)。展开更多
The Belt and Road Initiative and Xinjiang Editors:Foreign Affairs Office of the People’s Government of Xinjiang Uygur Autonomous Region&China Global Television Network of China Media Group Paperback,187 pages Pub...The Belt and Road Initiative and Xinjiang Editors:Foreign Affairs Office of the People’s Government of Xinjiang Uygur Autonomous Region&China Global Television Network of China Media Group Paperback,187 pages Published by Foreign Languages Press As a key junction along the ancient Silk Road,Xinjiang served as a vital crossroads for cultural exchanges between the Eastern and Western civilizations.Thanks to its unique geographic advantages,the region has been designated as a core area of the Belt and Road Initiative(BRI)and is playing a pivotal role in China’s westward opening-up.展开更多
Urbanization destroys wildlife habitats,fragmenting them into small patches with poor connectivity,leading to population declines in species sensitive to such chan ges.Escape is the most common anti-predator strategy ...Urbanization destroys wildlife habitats,fragmenting them into small patches with poor connectivity,leading to population declines in species sensitive to such chan ges.Escape is the most common anti-predator strategy adopted by birds,refuges in habitats reduce or eliminate predation risk.Therefore,creating habitats with suitable refuges for birds has significant implications for their conservation.However,there have been few studies on refuge selection in birds.This study examined the Eurasian Tree Sparrow(Passer montanus)and Oriental Magpie(Pica serica)in urban and rural areas of Chengde City,northern China by measuring their alert distance(AD),flight initiation distance(FID),an d distance fled(DF)and analyzed their refuge selection characteristics after escaping.The FID/AD ratio was employed to assess the behavioral differences of birds in the risk trade-off.The results showed that the FID and FID/AD of both species were lower in urban areas than in rural areas and were negatively correlated with immediate human density.Sparrow FID was significantly affected by group size and landing substrate type.The FID of sparrows was positively correlated with the group size.The sparrows that fled to bushes escaped earlier.In urban and rural areas,sparrows exhibited significantly lower FID,DF,and FID/AD than magpies.The species adopted different refuge selection strategies,with magpies preferentially selecting trees with greater vertical height and sparrows selecting both trees and bushes.Further analysis indicated that the horizontal and vertical distances fled of both species were lower when fleeing to bushes.Urban planning and conservation areas construction should incorporate the ecological needs of local bird species to rationally configure their habitat structure,thereby optimizing the effect of avian conservation.展开更多
High-performance magnesium alloys are in great demand to meet the lightweight design requirements of aircraft.Grain size has long been recognized as a key factor influencing the mechanical properties of alloys.This st...High-performance magnesium alloys are in great demand to meet the lightweight design requirements of aircraft.Grain size has long been recognized as a key factor influencing the mechanical properties of alloys.This study investigates the effect of grain size,controlled by Zr addition,on the fatigue behavior of a recently developed low-cost Mg-2.6Nd-0.35Zn alloy,through systematic characterization and analysis of stress-life(S-N)curves,fatigue crack propagation,fracture surface morphology,stress intensity factor,and crack propagation threshold.The results show that after heat treatment(solution at 525±5℃ for 8 h and water quenching at 60-80℃,followed by aging at 250±5℃for 14 h and then air cooling),coarse-grained specimens(average grain size approximately 596μm)containing 0.12wt.%Zr exhibit greater resistance to fatigue crack propagation than fine-grained specimens(average grain size approximately 94μm)containing 0.46wt.%Zr.Coarse grains promote intergranular fracture,while fine grains favor transgranular fracture.In addition,coarse grains reduce the sensitivity of the crack tip to stress concentration.Furthermore,fine-grained samples demonstrate a longer total fatigue life,owing to their superior resistance to crack initiation,which significantly prolongs the crack initiation stage.These findings highlight the importance of optimizing grain size to achieve the best possible fatigue resistance in Mg-Nd-Zn-Zr alloys for practical engineering applications.展开更多
Coal-derived hard carbon(HC)represents a promising anode material for sodium-ion batteries owing to its cost-effectiveness and high carbon yield.However,conventional carbonization induces excessive graphitization,yiel...Coal-derived hard carbon(HC)represents a promising anode material for sodium-ion batteries owing to its cost-effectiveness and high carbon yield.However,conventional carbonization induces excessive graphitization,yielding insufficient interlayer spacing(d_(002)<0.37 nm)and underdeveloped closed pores.Herein,we propose a dynamic crystallization control strategy through carbothermal shock treatment(1300°C,30 s)that decouples thermodynamic and kinetic constraints.This method precisely modulates graphite domain ordering kinetics,producing short-range ordered structures with expanded interlayer spacing(d_(002)=0.385 nm)and homogeneously distributed closed nanopores.Through combined in situ characterization and first-principles calculations,we elucidate a three-stage crystallization mechanism:(i)amorphous carbon transformation,(ii)open-pore collapse,and(iii)pseudo-graphitic ordering.The optimized HC achieves record performance with 88.6%initial Coulombic efficiency and 204 mA h g^(−1)plateau capacity,while its optimal interlayer spacing lowers Na+diffusion barriers to enable exceptional rate capability(221 mA h g^(−1)at 0.5C after 300 cycles).Practical pouch cells maintain 85%capacity retention after 100 cycles at−20°C and deliver 284 Wh kg^(−1)energy density.This work establishes a kinetic regulation paradigm for graphitization-prone precursors,advancing the rational design of high-performance HC anodes.展开更多
In deep coal mining,surrounding rock is subjected to both high in-situ stress and intense mining disturbances,leading to significant time-dependent behavior.Accurately capturing this behavior is essential for predicti...In deep coal mining,surrounding rock is subjected to both high in-situ stress and intense mining disturbances,leading to significant time-dependent behavior.Accurately capturing this behavior is essential for predicting long-term roadway stability,necessitating the development of a reliable constitutive creep model and numerical simulation approach.In this study,creep experiments were conducted on pre-damaged rock with varying initial damage levels to investigate the time-dependent mechanical properties.Based on the experimental results,an accelerated-creep criterion was proposed,and an elastic-viscoplastic creep damage model(EVPCD)was established that simultaneously considers the effects of time-dependent damage and instantaneous damage caused by stress disturbances on rock creep behavior.Subsequently,the effectiveness of the proposed creep model was verified using experimental data,and the secondary development of the EVPCD model was completed based on the FLAC3D platform.Following this,a long-term stability analysis method of deep surrounding rock that accounts for excavation-and mining-induced disturbances was proposed.Using the main roadway of Xutuan Coal Mine as a case study,numerical simulations were carried out to investigate the time-dependent deformation and failure characteristics of the surrounding rock following excavation and mining disturbance.Combined with on-site monitoring of the surrounding rock damage areas,the results indicate that the EVPCD outperforms the CVISC and Nishihara models in predicting the time-dependent behavior of deep surrounding rock.展开更多
The interrupted fatigue test method was utilized to investigate the damage evolution mechanism of the notch high-cycle fatigue(NHCF)in Ti-55531 alloy with a multilevel lamellar microstructure.The results reveal that s...The interrupted fatigue test method was utilized to investigate the damage evolution mechanism of the notch high-cycle fatigue(NHCF)in Ti-55531 alloy with a multilevel lamellar microstructure.The results reveal that significant microvoids and microcracks predominantly initiate at α/β interfaces under various notch root radii(R).Notably,even under larger R(0.75 mm),mutual interactions of stacking faults(SFs)−deformation twins,twins−twins,and SFs−SFs are observed.Furthermore,with decreasing R(0.34 and 0.14 mm),the volume fraction of SFs escalates significantly and twins are almost absent.Moreover,activated prismatic slip system decreases with a decrease in Schmidt factor and with the further decrease in R.Finally,strain localization near α/β interfaces contributes to the initiation of fatigue microcracks.展开更多
In Xujiadai,a small village in east China,baseball,a niche sport in the country,has become an engine for rural growth.To date,the village,located in Jiaxing City,Zhejiang Province,has hosted over ioo baseball and soft...In Xujiadai,a small village in east China,baseball,a niche sport in the country,has become an engine for rural growth.To date,the village,located in Jiaxing City,Zhejiang Province,has hosted over ioo baseball and softball tournaments,earning it the title of China's No.I Baseball Village.A decade ago,most villagers in Xujiadai were engaged in pig farming.In recent years,as China advanced nationwide rural environmental improvement efforts,the village also undertook cleanup initiatives.展开更多
The operational Tropical Regional Atmospheric Model System(TRAMS)often underestimates initial typhoon intensity when using the global analysis field as the initial condition.The TRAMS tropical cyclone(TC)initializatio...The operational Tropical Regional Atmospheric Model System(TRAMS)often underestimates initial typhoon intensity when using the global analysis field as the initial condition.The TRAMS tropical cyclone(TC)initialization scheme,developed based on the incremental analysis updates(IAU)technique,effectively reduces initial bias.However,the original IAU-based TC initialization scheme only adjusts the wind field at the analysis moment,with other variables adjusted implicitly under the model's constraints according to a gradually inserted wind increment(named“univariate adjustment scheme”hereafter).The univariate adjustment scheme requires approximately 3 h to reach a dynamic equilibrium state,which constrains the assimilation of hourly TC observations and causes excessive dissipation of meaningful short-wave information in adjustment increments.To address this limitation,this study develops a multivariate adjustment IAU-based TC initialization scheme that incorporates gradient wind balance and hydrostatic balance as its largescale constraints.Numerical experiments with TC Hato(2017)demonstrate that the multivariate adjustment scheme reduces the IAU relaxation time to 1 h while marginally improving forecast skill.These findings are consistently replicated across 12 additional TC cases.The development of the IAU-based multivariate adjustment initialization scheme establishes a foundation for 4-D initialization using hourly TC observations.展开更多
Stanbic Bank Zimbabwe is strategically positioning itself as a critical bridge for Zimbabwe’s local businesses,seeking to navigate the vast and complex Chinese market.
As we enter the year 2026,the international system continues to receive shocks from Donald Trump,arguably the 21st century’s most disruptive US leader.His return to the White House in 2025 coincided with the 80th ann...As we enter the year 2026,the international system continues to receive shocks from Donald Trump,arguably the 21st century’s most disruptive US leader.His return to the White House in 2025 coincided with the 80th anniversary of the defeat of fascism and the establishment of the United Nations,the multilateral platform that carried the world’s hope for peace,restraint and collective security.The coincidence was unsettling.A world order designed to limit power now confronts a moment in which power is exercised openly,transactionally and unapologetically.展开更多
To investigate the long-term stability of soft-hard interbedded rock masses with initial damage induced by earthquakes and periodic drying and wetting,this study prepared samples with different initial damage through ...To investigate the long-term stability of soft-hard interbedded rock masses with initial damage induced by earthquakes and periodic drying and wetting,this study prepared samples with different initial damage through cyclic loading and unloading(CLU)experiments followed by cyclic drying and wetting(CDW)experiments,and finally conducted creep experiments.The study analyzed the effects of initial damage on creep mechanical behavior,crack evolution,and explored failure precursor information,revealing the damage failure mechanisms.The results show that the structural characteristics of the rock mass control its macroscopic failure mode.Initial damage promotes microcrack development,influences the fracture mode,and increases the proportion of high-frequency(200−280 kHz)acoustic emission events during creep.Meanwhile,initial damage exacerbates creep characteristics,increasing the creep rate,shortening total creep failure time,and reducing long-term strength.The damage failure is attributed to:the generation of internal cracks and pores in the rock caused by CLU;mineral hydrolysis and expansion-contraction due to CDW,resulting in weakened intergranular cementation;and full development of cracks and pores under creep stress.Additionally,the deformation difference coefficient and the coefficient of variation of RA/AF values can serve as precursor indicators for creep failure.展开更多
The influence of different solution and aging conditions on the microstructure,impact toughness,and crack initiation and propagation mechanisms of the novel α+β titanium alloy Ti6422 was systematically investigated....The influence of different solution and aging conditions on the microstructure,impact toughness,and crack initiation and propagation mechanisms of the novel α+β titanium alloy Ti6422 was systematically investigated.By adjusting the furnace cooling time after solution treatment and the aging temperature,Ti6422 alloy samples were developed with a multi-level lamellar microstructure,in-cluding microscaleαcolonies and α_(p) lamellae,as well as nanoscale α_(s) phases.Extending the furnace cooling time after solution treatment at 920℃ for 1 h from 240 to 540 min,followed by aging at 600℃ for 6 h,increased the α_(p) lamella content,reduced the α_(s) phase content,expanded theαcolonies and α_(p) lamellae size,and improved the impact toughness from 22.7 to 53.8 J/cm^(2).Additionally,under the same solution treatment,raising the aging temperature from 500 to 700℃ resulted in a decrease in the α_(s) phase content and a growth in the thickness of the α_(p) lamella and α_(s) phase.The impact toughness increased significantly with these changes.Samples with high α_(p) lamellae content or large α_(s) phase size exhibited high crack initiation and propagation energies.Impact deformation caused severe kinking of the α_(p) lamellae in crack initiation and propagation areas,leading to a uniform and high-density kernel average misorientation(KAM)distribu-tion,enhancing plastic deformation coordination and uniformity.Moreover,the multidirectional arrangement of coarserαcolonies and α_(p) lamellae continuously deflect the crack propagation direction,inhibiting crack propagation.展开更多
April 23,global celebration&webcastInternational Girls in ICT Day has been a flagship ITU initiative since 2011,aimed at encouraging girls and young women to pursue studies and careers in information and communica...April 23,global celebration&webcastInternational Girls in ICT Day has been a flagship ITU initiative since 2011,aimed at encouraging girls and young women to pursue studies and careers in information and communication technologies (ICT).It focuses on awareness raising on the opportunities that ICT can provide for educational and socio-economic empowerment of girls and young women.展开更多
The stability of rock slopes is frequently controlled by the initiation and propagation of inherent dominant cracks.This study systematically investigated these processes in valley slopes by combining fracture-mechani...The stability of rock slopes is frequently controlled by the initiation and propagation of inherent dominant cracks.This study systematically investigated these processes in valley slopes by combining fracture-mechanics analysis with transparent soil model tests.An analytical expression for the stress field at the dominant crack tip was derived from the slope stress distribution by superposing the corresponding stress intensity factors(SIFs).The theoretical predictions were then validated against observations from transparent soil model tests.The influences of slope angle(β),crack inclination angle(α),crack position parameter(b),and crack length parameter(h)on crack initiation and propagation were quantified.The results indicated that:(1)cracks at the slope crest tended to propagate in shear mode,and the shear crack initiation angle(θ_(s))was approximately 8°.Cracks at the slope toe might propagate in either tensile or shear mode.(2)θ_(s) at the slope crest increased withβ,b,and l,and decreased withα.The maximum change inθ_(s) induced by the considered parameters was approximately 30°.(3)The tensile crack initiation angle(θ_(t))at the slop toe decreased withβ,α,and l,while the influence of b was comparatively minor.The maximum change inθ_(t) caused by individual parameters ranged approximately from 25°to 60°.Predicted crack propagation modes and directions showed good agreement with experimental results.These findings provide theoretical guidance for stability assessments of valley slopes controlled by dominant crack propagation.展开更多
The cemented tailings backfill(CTB)with initial defects is more prone to destabilization damage under the influence of various unfavorable factors during the mining process.In order to investigate its influence on the...The cemented tailings backfill(CTB)with initial defects is more prone to destabilization damage under the influence of various unfavorable factors during the mining process.In order to investigate its influence on the stability of underground mining engineering,this paper simulates the generation of different degrees of initial defects inside the CTB by adding different contents of air-entraining agent(AEA),investigates the acoustic emission RA/AF eigenvalues of CTB with different contents of AEA under uniaxial compression,and adopts various denoising algorithms(e.g.,moving average smoothing,median filtering,and outlier detection)to improve the accuracy of the data.The variance and autocorrelation coefficients of RA/AF parameters were analyzed in conjunction with the critical slowing down(CSD)theory.The results show that the acoustic emission RA/AF values can be used to characterize the progressive damage evolution of CTB.The denoising algorithm processed the AE signals to reduce the effects of extraneous noise and anomalous spikes.Changes in the variance curves provide clear precursor information,while abrupt changes in the autocorrelation coefficient can be used as an auxiliary localization warning signal.The phenomenon of dramatic increase in the variance and autocorrelation coefficient curves during the compression-tightening stage,which is influenced by the initial defects,can lead to false warnings.As the initial defects of the CTB increase,its instability precursor time and instability time are prolonged,the peak stress decreases,and the time difference between the CTB and the instability damage is smaller.The results provide a new method for real-time monitoring and early warning of CTB instability damage.展开更多
Amyloid-β(Aβ)and tau,the two hallmark proteins associated with Alzheimer’s disease(AD),exhibit distinct toxic effects but also interact synergistically within the disease pathology.The prevailing theory in AD patho...Amyloid-β(Aβ)and tau,the two hallmark proteins associated with Alzheimer’s disease(AD),exhibit distinct toxic effects but also interact synergistically within the disease pathology.The prevailing theory in AD pathology-the amyloid cascade hypothesis-highlights the pivotal role of increased processing of the amyloid precursor protein(APP).Initially cleaved by the majorβ-secretase(β-amyloid cleaving enzyme-1,BACE1)in the brain,then undergoes further cleavage by theγ-secretase complex,resulting in the production of Aβ_(40-42)and a set of intracellular C-terminal peptides known as Aβand APP intracellular domain(β-AICDs)and soluble amyloid precursor proteinβ(sAPPβ)(Orobets and Karamyshev,2023).展开更多
The effects of initial spin orientation on the final electron beam polarization in laser wakefield acceleration in a pre-polarized plasma are investigated theoretically and numerically.From the results of variation of...The effects of initial spin orientation on the final electron beam polarization in laser wakefield acceleration in a pre-polarized plasma are investigated theoretically and numerically.From the results of variation of the initial spin direction,the spin dynamics of the electron beam are found to depend on the self-injection mechanism.The effects of wakefields and laser fields are studied using test particle dynamics and particle-in-cell simulations based on the Thomas-Bargmann-Michel-Telegdi equation.Compared with transverse injection,longitudinal injection is found to be preferable for obtaining a highly polarized electron beam.展开更多
The NSC-34 cell line is a widely recognized motor neuron model and various neuronal differentiation protocols have been exploited. Under previously reported experimental conditions, only part of the cells resemble dif...The NSC-34 cell line is a widely recognized motor neuron model and various neuronal differentiation protocols have been exploited. Under previously reported experimental conditions, only part of the cells resemble differentiated neurons;however, they do not exhibit extensive and time-prolonged neuritogenesis, and maintain their duplication capacity in culture. The aim of the present work was to facilitate long-term and more homogeneous neuronal differentiation in motor neuron–like NSC-34 cells. We found that the antimitotic drug cytosine arabinoside promoted robust and persistent neuronal differentiation in the entire cell population. Long and interconnecting neuronal processes with abundant growth cones were homogeneously induced and were durable for up to at least 6 weeks in culture. Moreover, cytosine arabinoside was permissive, dispensable, and mostly irreversible in priming NSC-34 cells for neurite initiation and regeneration after mechanical dislodgement. Finally, the expression of the cell proliferation antigen Ki67 was inhibited by cytosine arabinoside, whereas the expression levels of neuronal growth associated protein 43, vimentin, and motor neuron–specific p75, Islet2, homeobox 9 markers were upregulated, as confirmed by western blot and/or confocal immunofluorescence analysis. Overall, these findings support the use of NSC-34 cells as a motor neuron model for properly investigating neurodegenerative mechanisms and prospectively identifying neuroprotective strategies.展开更多
In an era of profound changes to global trade,food security,and industrial organization,the ChinaIndonesia“Two Countries,Twin Parks”initiative has emerged as a strategic experiment with farreaching implications.Anch...In an era of profound changes to global trade,food security,and industrial organization,the ChinaIndonesia“Two Countries,Twin Parks”initiative has emerged as a strategic experiment with farreaching implications.Anchored in marine protein processing and advanced food manufacturing,this collaboration reflects not only a convergence of economic interests but also a deliberate rethinking of how China engages with global resources,technology,and partners.展开更多
文摘Nature|大型汉族人群队列助力中国台湾精准医疗精准医学的发展依赖于大规模、具有深度表型和基因变异图谱数据的人群队列,然而这在非欧洲人群中数据仍严重不足。中国台湾精准医学计划(Taiwan Precision Medicine Initiative,TPMI)旨在建立一个具有广泛代表性的中国台湾汉族人群队列,以支持大规模基因组与健康医学研究(2025年10月15日在线发表,doi:10.1038/s41586-025-09680-x)。
文摘The Belt and Road Initiative and Xinjiang Editors:Foreign Affairs Office of the People’s Government of Xinjiang Uygur Autonomous Region&China Global Television Network of China Media Group Paperback,187 pages Published by Foreign Languages Press As a key junction along the ancient Silk Road,Xinjiang served as a vital crossroads for cultural exchanges between the Eastern and Western civilizations.Thanks to its unique geographic advantages,the region has been designated as a core area of the Belt and Road Initiative(BRI)and is playing a pivotal role in China’s westward opening-up.
基金funded by the Natural Science Foundation of Hebei Province(C2025201032 to J.W.)High-Level Talents Research Start-Up Project of Hebei University(521100222044 to J.W.)+1 种基金the Huizhi Lead Innovation Space Project in High-tech Zone of Chengde City(HZLC202410 to L.M.)National Undergraduate Innovation and Entrepreneurship Training Program(202510098011 to H.Z.)。
文摘Urbanization destroys wildlife habitats,fragmenting them into small patches with poor connectivity,leading to population declines in species sensitive to such chan ges.Escape is the most common anti-predator strategy adopted by birds,refuges in habitats reduce or eliminate predation risk.Therefore,creating habitats with suitable refuges for birds has significant implications for their conservation.However,there have been few studies on refuge selection in birds.This study examined the Eurasian Tree Sparrow(Passer montanus)and Oriental Magpie(Pica serica)in urban and rural areas of Chengde City,northern China by measuring their alert distance(AD),flight initiation distance(FID),an d distance fled(DF)and analyzed their refuge selection characteristics after escaping.The FID/AD ratio was employed to assess the behavioral differences of birds in the risk trade-off.The results showed that the FID and FID/AD of both species were lower in urban areas than in rural areas and were negatively correlated with immediate human density.Sparrow FID was significantly affected by group size and landing substrate type.The FID of sparrows was positively correlated with the group size.The sparrows that fled to bushes escaped earlier.In urban and rural areas,sparrows exhibited significantly lower FID,DF,and FID/AD than magpies.The species adopted different refuge selection strategies,with magpies preferentially selecting trees with greater vertical height and sparrows selecting both trees and bushes.Further analysis indicated that the horizontal and vertical distances fled of both species were lower when fleeing to bushes.Urban planning and conservation areas construction should incorporate the ecological needs of local bird species to rationally configure their habitat structure,thereby optimizing the effect of avian conservation.
文摘High-performance magnesium alloys are in great demand to meet the lightweight design requirements of aircraft.Grain size has long been recognized as a key factor influencing the mechanical properties of alloys.This study investigates the effect of grain size,controlled by Zr addition,on the fatigue behavior of a recently developed low-cost Mg-2.6Nd-0.35Zn alloy,through systematic characterization and analysis of stress-life(S-N)curves,fatigue crack propagation,fracture surface morphology,stress intensity factor,and crack propagation threshold.The results show that after heat treatment(solution at 525±5℃ for 8 h and water quenching at 60-80℃,followed by aging at 250±5℃for 14 h and then air cooling),coarse-grained specimens(average grain size approximately 596μm)containing 0.12wt.%Zr exhibit greater resistance to fatigue crack propagation than fine-grained specimens(average grain size approximately 94μm)containing 0.46wt.%Zr.Coarse grains promote intergranular fracture,while fine grains favor transgranular fracture.In addition,coarse grains reduce the sensitivity of the crack tip to stress concentration.Furthermore,fine-grained samples demonstrate a longer total fatigue life,owing to their superior resistance to crack initiation,which significantly prolongs the crack initiation stage.These findings highlight the importance of optimizing grain size to achieve the best possible fatigue resistance in Mg-Nd-Zn-Zr alloys for practical engineering applications.
基金supported by the Key Laboratory of Sichuan Province for Lithium Resources Comprehensive Utilization and New Lithium Based Materials for Advanced Battery Technology(LRMKF202405)the National Natural Science Foundation of China(52402226)the Natural Science Foundation of Sichuan Province(2024NSFSC1016).
文摘Coal-derived hard carbon(HC)represents a promising anode material for sodium-ion batteries owing to its cost-effectiveness and high carbon yield.However,conventional carbonization induces excessive graphitization,yielding insufficient interlayer spacing(d_(002)<0.37 nm)and underdeveloped closed pores.Herein,we propose a dynamic crystallization control strategy through carbothermal shock treatment(1300°C,30 s)that decouples thermodynamic and kinetic constraints.This method precisely modulates graphite domain ordering kinetics,producing short-range ordered structures with expanded interlayer spacing(d_(002)=0.385 nm)and homogeneously distributed closed nanopores.Through combined in situ characterization and first-principles calculations,we elucidate a three-stage crystallization mechanism:(i)amorphous carbon transformation,(ii)open-pore collapse,and(iii)pseudo-graphitic ordering.The optimized HC achieves record performance with 88.6%initial Coulombic efficiency and 204 mA h g^(−1)plateau capacity,while its optimal interlayer spacing lowers Na+diffusion barriers to enable exceptional rate capability(221 mA h g^(−1)at 0.5C after 300 cycles).Practical pouch cells maintain 85%capacity retention after 100 cycles at−20°C and deliver 284 Wh kg^(−1)energy density.This work establishes a kinetic regulation paradigm for graphitization-prone precursors,advancing the rational design of high-performance HC anodes.
基金funded by the National Natural Science Foundation of China(Nos.52004098,U24B2041,and 52274079)the Key Research and Development Program of Henan Province(No.251111320400)+1 种基金the Key Research Project Plan for Higher Education Institutions in Henan Province(Nos.24A570006 and 25A570002)the Scientific and Technological Research Project in Henan Province(No.242102320061).
文摘In deep coal mining,surrounding rock is subjected to both high in-situ stress and intense mining disturbances,leading to significant time-dependent behavior.Accurately capturing this behavior is essential for predicting long-term roadway stability,necessitating the development of a reliable constitutive creep model and numerical simulation approach.In this study,creep experiments were conducted on pre-damaged rock with varying initial damage levels to investigate the time-dependent mechanical properties.Based on the experimental results,an accelerated-creep criterion was proposed,and an elastic-viscoplastic creep damage model(EVPCD)was established that simultaneously considers the effects of time-dependent damage and instantaneous damage caused by stress disturbances on rock creep behavior.Subsequently,the effectiveness of the proposed creep model was verified using experimental data,and the secondary development of the EVPCD model was completed based on the FLAC3D platform.Following this,a long-term stability analysis method of deep surrounding rock that accounts for excavation-and mining-induced disturbances was proposed.Using the main roadway of Xutuan Coal Mine as a case study,numerical simulations were carried out to investigate the time-dependent deformation and failure characteristics of the surrounding rock following excavation and mining disturbance.Combined with on-site monitoring of the surrounding rock damage areas,the results indicate that the EVPCD outperforms the CVISC and Nishihara models in predicting the time-dependent behavior of deep surrounding rock.
基金supported by the National Natural Science Foundation of China(Nos.52061005,52261025)the Science and Technology Programs of Guizhou Province,China(Nos.YQK[2023]009,CXTD[2023]009)the Technology Innovation Leading Program of Shaanxi Province,China(No.2024ZCYYDP92)。
文摘The interrupted fatigue test method was utilized to investigate the damage evolution mechanism of the notch high-cycle fatigue(NHCF)in Ti-55531 alloy with a multilevel lamellar microstructure.The results reveal that significant microvoids and microcracks predominantly initiate at α/β interfaces under various notch root radii(R).Notably,even under larger R(0.75 mm),mutual interactions of stacking faults(SFs)−deformation twins,twins−twins,and SFs−SFs are observed.Furthermore,with decreasing R(0.34 and 0.14 mm),the volume fraction of SFs escalates significantly and twins are almost absent.Moreover,activated prismatic slip system decreases with a decrease in Schmidt factor and with the further decrease in R.Finally,strain localization near α/β interfaces contributes to the initiation of fatigue microcracks.
文摘In Xujiadai,a small village in east China,baseball,a niche sport in the country,has become an engine for rural growth.To date,the village,located in Jiaxing City,Zhejiang Province,has hosted over ioo baseball and softball tournaments,earning it the title of China's No.I Baseball Village.A decade ago,most villagers in Xujiadai were engaged in pig farming.In recent years,as China advanced nationwide rural environmental improvement efforts,the village also undertook cleanup initiatives.
基金supported by the National University of Defense Technology(NUDT)Research Initiation Funding for High-Level Scientific and Technological Innovative Talents(202402-YJRC-LJ-001)the National Natural Science Foundation of China(Grant No.U2142213)+1 种基金the Basic and Applied Basic Research Foundation of Guangdong Province(Grants 2025A1515011835,2022A1515011870)the National Natural Science Foundation of China(Grant No.42305167)。
文摘The operational Tropical Regional Atmospheric Model System(TRAMS)often underestimates initial typhoon intensity when using the global analysis field as the initial condition.The TRAMS tropical cyclone(TC)initialization scheme,developed based on the incremental analysis updates(IAU)technique,effectively reduces initial bias.However,the original IAU-based TC initialization scheme only adjusts the wind field at the analysis moment,with other variables adjusted implicitly under the model's constraints according to a gradually inserted wind increment(named“univariate adjustment scheme”hereafter).The univariate adjustment scheme requires approximately 3 h to reach a dynamic equilibrium state,which constrains the assimilation of hourly TC observations and causes excessive dissipation of meaningful short-wave information in adjustment increments.To address this limitation,this study develops a multivariate adjustment IAU-based TC initialization scheme that incorporates gradient wind balance and hydrostatic balance as its largescale constraints.Numerical experiments with TC Hato(2017)demonstrate that the multivariate adjustment scheme reduces the IAU relaxation time to 1 h while marginally improving forecast skill.These findings are consistently replicated across 12 additional TC cases.The development of the IAU-based multivariate adjustment initialization scheme establishes a foundation for 4-D initialization using hourly TC observations.
文摘Stanbic Bank Zimbabwe is strategically positioning itself as a critical bridge for Zimbabwe’s local businesses,seeking to navigate the vast and complex Chinese market.
文摘As we enter the year 2026,the international system continues to receive shocks from Donald Trump,arguably the 21st century’s most disruptive US leader.His return to the White House in 2025 coincided with the 80th anniversary of the defeat of fascism and the establishment of the United Nations,the multilateral platform that carried the world’s hope for peace,restraint and collective security.The coincidence was unsettling.A world order designed to limit power now confronts a moment in which power is exercised openly,transactionally and unapologetically.
基金Project(U22A20603)supported by the National Natural Science Foundation of ChinaProject(2023YFC3008300)supported by the National Key Research and Development Program of China。
文摘To investigate the long-term stability of soft-hard interbedded rock masses with initial damage induced by earthquakes and periodic drying and wetting,this study prepared samples with different initial damage through cyclic loading and unloading(CLU)experiments followed by cyclic drying and wetting(CDW)experiments,and finally conducted creep experiments.The study analyzed the effects of initial damage on creep mechanical behavior,crack evolution,and explored failure precursor information,revealing the damage failure mechanisms.The results show that the structural characteristics of the rock mass control its macroscopic failure mode.Initial damage promotes microcrack development,influences the fracture mode,and increases the proportion of high-frequency(200−280 kHz)acoustic emission events during creep.Meanwhile,initial damage exacerbates creep characteristics,increasing the creep rate,shortening total creep failure time,and reducing long-term strength.The damage failure is attributed to:the generation of internal cracks and pores in the rock caused by CLU;mineral hydrolysis and expansion-contraction due to CDW,resulting in weakened intergranular cementation;and full development of cracks and pores under creep stress.Additionally,the deformation difference coefficient and the coefficient of variation of RA/AF values can serve as precursor indicators for creep failure.
基金supported by the National Natural Science Foundation of China(No.52090041).
文摘The influence of different solution and aging conditions on the microstructure,impact toughness,and crack initiation and propagation mechanisms of the novel α+β titanium alloy Ti6422 was systematically investigated.By adjusting the furnace cooling time after solution treatment and the aging temperature,Ti6422 alloy samples were developed with a multi-level lamellar microstructure,in-cluding microscaleαcolonies and α_(p) lamellae,as well as nanoscale α_(s) phases.Extending the furnace cooling time after solution treatment at 920℃ for 1 h from 240 to 540 min,followed by aging at 600℃ for 6 h,increased the α_(p) lamella content,reduced the α_(s) phase content,expanded theαcolonies and α_(p) lamellae size,and improved the impact toughness from 22.7 to 53.8 J/cm^(2).Additionally,under the same solution treatment,raising the aging temperature from 500 to 700℃ resulted in a decrease in the α_(s) phase content and a growth in the thickness of the α_(p) lamella and α_(s) phase.The impact toughness increased significantly with these changes.Samples with high α_(p) lamellae content or large α_(s) phase size exhibited high crack initiation and propagation energies.Impact deformation caused severe kinking of the α_(p) lamellae in crack initiation and propagation areas,leading to a uniform and high-density kernel average misorientation(KAM)distribu-tion,enhancing plastic deformation coordination and uniformity.Moreover,the multidirectional arrangement of coarserαcolonies and α_(p) lamellae continuously deflect the crack propagation direction,inhibiting crack propagation.
文摘April 23,global celebration&webcastInternational Girls in ICT Day has been a flagship ITU initiative since 2011,aimed at encouraging girls and young women to pursue studies and careers in information and communication technologies (ICT).It focuses on awareness raising on the opportunities that ICT can provide for educational and socio-economic empowerment of girls and young women.
基金financially supported by the National Nature Science Foundation of China(Nos.52379110 and 42207222)the Key Technologies for Accurate Diagnosis and Intelligent Prevention and Control of Slope Hazards in Open Pit Mines,181 Major R&D projects of Metallurgical Corporation of China Ltd。
文摘The stability of rock slopes is frequently controlled by the initiation and propagation of inherent dominant cracks.This study systematically investigated these processes in valley slopes by combining fracture-mechanics analysis with transparent soil model tests.An analytical expression for the stress field at the dominant crack tip was derived from the slope stress distribution by superposing the corresponding stress intensity factors(SIFs).The theoretical predictions were then validated against observations from transparent soil model tests.The influences of slope angle(β),crack inclination angle(α),crack position parameter(b),and crack length parameter(h)on crack initiation and propagation were quantified.The results indicated that:(1)cracks at the slope crest tended to propagate in shear mode,and the shear crack initiation angle(θ_(s))was approximately 8°.Cracks at the slope toe might propagate in either tensile or shear mode.(2)θ_(s) at the slope crest increased withβ,b,and l,and decreased withα.The maximum change inθ_(s) induced by the considered parameters was approximately 30°.(3)The tensile crack initiation angle(θ_(t))at the slop toe decreased withβ,α,and l,while the influence of b was comparatively minor.The maximum change inθ_(t) caused by individual parameters ranged approximately from 25°to 60°.Predicted crack propagation modes and directions showed good agreement with experimental results.These findings provide theoretical guidance for stability assessments of valley slopes controlled by dominant crack propagation.
基金Projects(52374138,51764013)supported by the National Natural Science Foundation of ChinaProject(20204BCJ22005)supported by the Training Plan for Academic and Technical Leaders of Major Disciplines of Jiangxi Province,China+1 种基金Project(2019M652277)supported by the China Postdoctoral Science FoundationProject(20192ACBL21014)supported by the Natural Science Youth Foundation Key Projects of Jiangxi Province,China。
文摘The cemented tailings backfill(CTB)with initial defects is more prone to destabilization damage under the influence of various unfavorable factors during the mining process.In order to investigate its influence on the stability of underground mining engineering,this paper simulates the generation of different degrees of initial defects inside the CTB by adding different contents of air-entraining agent(AEA),investigates the acoustic emission RA/AF eigenvalues of CTB with different contents of AEA under uniaxial compression,and adopts various denoising algorithms(e.g.,moving average smoothing,median filtering,and outlier detection)to improve the accuracy of the data.The variance and autocorrelation coefficients of RA/AF parameters were analyzed in conjunction with the critical slowing down(CSD)theory.The results show that the acoustic emission RA/AF values can be used to characterize the progressive damage evolution of CTB.The denoising algorithm processed the AE signals to reduce the effects of extraneous noise and anomalous spikes.Changes in the variance curves provide clear precursor information,while abrupt changes in the autocorrelation coefficient can be used as an auxiliary localization warning signal.The phenomenon of dramatic increase in the variance and autocorrelation coefficient curves during the compression-tightening stage,which is influenced by the initial defects,can lead to false warnings.As the initial defects of the CTB increase,its instability precursor time and instability time are prolonged,the peak stress decreases,and the time difference between the CTB and the instability damage is smaller.The results provide a new method for real-time monitoring and early warning of CTB instability damage.
文摘Amyloid-β(Aβ)and tau,the two hallmark proteins associated with Alzheimer’s disease(AD),exhibit distinct toxic effects but also interact synergistically within the disease pathology.The prevailing theory in AD pathology-the amyloid cascade hypothesis-highlights the pivotal role of increased processing of the amyloid precursor protein(APP).Initially cleaved by the majorβ-secretase(β-amyloid cleaving enzyme-1,BACE1)in the brain,then undergoes further cleavage by theγ-secretase complex,resulting in the production of Aβ_(40-42)and a set of intracellular C-terminal peptides known as Aβand APP intracellular domain(β-AICDs)and soluble amyloid precursor proteinβ(sAPPβ)(Orobets and Karamyshev,2023).
基金supported by the National Natural Science Foundation of China(Grant Nos.11804348,11775056,11975154,12225505,and 12405281)the Science Challenge(Project No.TZ2018005)+2 种基金supported by the Shanghai Pujiang Program(Grant No.23PJ1414600)the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDB0890203)supported by the Accelerator Technology Helmholtz Infrastructure consortium ATHENA.
文摘The effects of initial spin orientation on the final electron beam polarization in laser wakefield acceleration in a pre-polarized plasma are investigated theoretically and numerically.From the results of variation of the initial spin direction,the spin dynamics of the electron beam are found to depend on the self-injection mechanism.The effects of wakefields and laser fields are studied using test particle dynamics and particle-in-cell simulations based on the Thomas-Bargmann-Michel-Telegdi equation.Compared with transverse injection,longitudinal injection is found to be preferable for obtaining a highly polarized electron beam.
基金supported by FATALSDrug Project [Progetti di Ricerca@CNR SAC.AD002.173.058] from National Research Council,Italy (to CV)。
文摘The NSC-34 cell line is a widely recognized motor neuron model and various neuronal differentiation protocols have been exploited. Under previously reported experimental conditions, only part of the cells resemble differentiated neurons;however, they do not exhibit extensive and time-prolonged neuritogenesis, and maintain their duplication capacity in culture. The aim of the present work was to facilitate long-term and more homogeneous neuronal differentiation in motor neuron–like NSC-34 cells. We found that the antimitotic drug cytosine arabinoside promoted robust and persistent neuronal differentiation in the entire cell population. Long and interconnecting neuronal processes with abundant growth cones were homogeneously induced and were durable for up to at least 6 weeks in culture. Moreover, cytosine arabinoside was permissive, dispensable, and mostly irreversible in priming NSC-34 cells for neurite initiation and regeneration after mechanical dislodgement. Finally, the expression of the cell proliferation antigen Ki67 was inhibited by cytosine arabinoside, whereas the expression levels of neuronal growth associated protein 43, vimentin, and motor neuron–specific p75, Islet2, homeobox 9 markers were upregulated, as confirmed by western blot and/or confocal immunofluorescence analysis. Overall, these findings support the use of NSC-34 cells as a motor neuron model for properly investigating neurodegenerative mechanisms and prospectively identifying neuroprotective strategies.
文摘In an era of profound changes to global trade,food security,and industrial organization,the ChinaIndonesia“Two Countries,Twin Parks”initiative has emerged as a strategic experiment with farreaching implications.Anchored in marine protein processing and advanced food manufacturing,this collaboration reflects not only a convergence of economic interests but also a deliberate rethinking of how China engages with global resources,technology,and partners.
