Hydrogen energy has gained widespread recognition for its environmentally friendly nature,high energy density and abundant resources,making it a promising energy carrier for a sustainable and clean energy society.Howe...Hydrogen energy has gained widespread recognition for its environmentally friendly nature,high energy density and abundant resources,making it a promising energy carrier for a sustainable and clean energy society.However,safe and efficient hydrogen storage remains a significant challenge due to its inherent leakiness and flammability.To overcome these challenges,alloys featuring body-centered cubic(BCC)structures have emerged as compelling candidates for hydrogen storage,owing to their exceptional capacity to achieve high-density hydrogen storage up to 3.8 wt%at ambient temperatures.Nonetheless,their practical application faces limited dehydriding capacity,complex activation processes,high costs and poor cyclic stability.Various modification strategies have been explored to overcome these limitations,including lattice regulation,element substitution,rare earth doping and heat treatment.This progress report presents an overview of the previous advancements to enhance five crucial aspects(high-V,medium-V,low-V,V-free and high-entropy alloys)in composition design and hydrogen storage properties within BCC-structured alloys.Subsequently,an in-depth analysis is conducted to examine the relationship between crystal structures and hydrogen storage properties specific to BCC-structured alloys,covering aspects such as composition,crystal structure,hydrogen storage capacity,enthalpy and entropy.Furthermore,this review explores current challenges in this field and outlines directions for future research.These insights provide valuable guidance for the design of innovative and cost-effective hydrogen storage alloys.展开更多
The equiatomic and equimass TiHfMo,TiHfMoNb and TiHfMoNbZr alloys were prepared,and their microstructure,mechanical properties and bio-corrosion behaviors were systematically investigated.The results demonstrated that...The equiatomic and equimass TiHfMo,TiHfMoNb and TiHfMoNbZr alloys were prepared,and their microstructure,mechanical properties and bio-corrosion behaviors were systematically investigated.The results demonstrated that all the multi-principal element alloys(MPEAs)had a single BCC phase structure without any intermetallic compounds.Moreover,the Young’s moduli and hardness of the MPEAs were respectively within the range of 95−126 GPa and 5.5−6.4 GPa,respectively.In simulated body fluids,the MPEAs had excellent resistance to chloride ion attack due to the fact that the passive films consisted of multiple oxides and the surface possessed large contact angles.Compared with CP-Ti and Ti6Al4V alloy,equiatomic TiHfMo and TiHfMoNb alloys had a desirable combination of pitting and corrosion resistance,wettability,and wear resistance,and can be utilized as potential candidates for biomedical metallic implants.展开更多
Magnesium hydride(MgH_(2))has garnered significant attention as a promising material for high-capacity hydrogen storage.However,its commercial application remains challenging due to the high operating temperature and ...Magnesium hydride(MgH_(2))has garnered significant attention as a promising material for high-capacity hydrogen storage.However,its commercial application remains challenging due to the high operating temperature and slow reaction kinetics.In this study,melt-spun Ti_(45)Cr_(40)Nb_(15)(with a BCC phase)hydride(designated as TiCrNbH_(x-)MS)was synthesized and used to form a nano-multiphase composite to improve the de-/rehydrogenation properties of MgH_(2) through ball milling.The incorporation of TiCrNbH_(x-)MS was shown to significantly enhance the hydrogen de-/rehydrogenation properties of MgH_(2).The MgH_(2)+20 wt%TiCrNbH_(x-)MS composite exhibits an appealing initial dehydrogenation temperature of 163℃ and can absorb hydrogen at room temperature.Notably,it releases 5.8 wt% hydrogen in 700 s at 230℃ and recharges 4.3 wt%hydrogen in just 2 mins at 150℃.Even after 100 cycles,it retains a reversible hydrogen capacity of 4.98 wt%.Kinetic analysis revealed that the dehydrogenation rate follows the Chou surface penetration model.Microstructural analysis showed that the FCC phase of the melt-spun TiCrNbH_(x-)MS hydride reversibly transformed into the BCC phase during the de-/rehydrogenation process in the composite.Numerous phase interfaces were generated and uniformly dispersed on the MgH_(2) surface,providing additional hydrogen diffusion pathways and heterogeneous nucleation sites for Mg/MgH_(2),thereby further improving the hydrogen de-/rehydrogenation kinetics of the system.This study offers valuable insights into the use of multiphase composites to enhance MgH_(2) performance.展开更多
文章以新疆机场集团为研究对象,选取2013~2023年间的16个机场作为效率分析的目标,运用数据包络分析(DEA)方法,结合BCC模型以及Malmquist指数,从静态和动态两个维度对机场集团的运营效率进行了全面评估。研究结果表明:(1) 乌鲁木齐地窝...文章以新疆机场集团为研究对象,选取2013~2023年间的16个机场作为效率分析的目标,运用数据包络分析(DEA)方法,结合BCC模型以及Malmquist指数,从静态和动态两个维度对机场集团的运营效率进行了全面评估。研究结果表明:(1) 乌鲁木齐地窝堡国际机场(URC)和库尔勒机场(KRL)作为核心枢纽,其综合效率、技术效率和规模效率均表现优异。(2) 塔什库尔干机场(HQL)和奇台机场(JBK)等支线机场的效率值较低,表明其在资源配置、技术水平和规模匹配方面存在较大提升空间。(3) 技术进步(TC)是效率提升的主要驱动力,尤其是在博乐机场(BPL)和阿勒泰机场(AAT)中表现显著,而乌鲁木齐地窝堡国际机场(URC)和喀什机场(KHG)的效率下降则可能与规模过大、资源配置不合理或区域经济波动有关。This paper takes Xinjiang Airport Group as the research object, selects 16 airports from 2013 to 2023 as the efficiency analysis targets, uses data enveloping analysis (DEA) method, combines BCC model and Malmquist index, and comprehensively evaluates the operational efficiency of the airport group from both static and dynamic dimensions. The results show that: (1) Urumqi Diwopu International Airport (URC) and Korla Airport (KRL), as the core hubs, have excellent performance in comprehensive efficiency, technical efficiency and scale efficiency. (2) The efficiency values of regional airports such as Tashkourgan Airport (HQL) and Qitai Airport (JBK) are low, indicating that there is a large room for improvement in terms of resource allocation, technical level and scale matching. (3) Technological progress (TC) is the main driving force of efficiency improvement, especially in BPL and Altai Airports (AAT), while the efficiency decline of Urumqi Diwopu International Airport (URC) and Kashgar Airport (KHG) may be related to excessive scale, unreasonable resource allocation or regional economic fluctuations.展开更多
Basal cell carcinoma(BCC)is the most prevalent form of skin cancer in the world,primarily affecting sun-exposed areas,including the periocular region.When BCC occurs near the eyes,surgical treatment becomes uniquely c...Basal cell carcinoma(BCC)is the most prevalent form of skin cancer in the world,primarily affecting sun-exposed areas,including the periocular region.When BCC occurs near the eyes,surgical treatment becomes uniquely complex.Excess excisions may cause detrimental effects to eyelid function and undesirable aesthetic outcomes.Conversely,adequate resection must occur to prevent further disease progression.Mohs micrographic surgery(MMS),a technique offering high remission rates,is often employed for periocular BCC.This method allows for precise cancer removal while preserving as much healthy tissue as possible,balancing the need for both effective treatment and aesthetic and functional preservation.Following Mohs surgery of periocular BCC,reconstruction methods vary and can be tailored based on the size of the resection and the functional requirements of the affected tissue.Amongst these methods,primary closure with and without secondary intentions,direct margin repair,local flap closure and advance flap,Tenzel flap,tarso-conjunctival flap,periocular skin grafting,and structural grafting are commonly utilized and each has its advantages and limitations.In the future,advancements in synthetic flaps and stabilizing glues in the periocular region may provide additional tools for post-Mohs reconstruction.However,these emerging techniques require further research to establish efficacy and safety,especially in more complex and sensitive regions like the periocular tissues.The primary purpose of this review is to provide a comprehensive analysis of periocular reconstructive techniques following Mohs surgery,comparing their efficacy,functional outcomes,and aesthetic considerations while addressing recent advancements such as synthetic flaps and stabilizing glues to guide clinical decision-making.展开更多
基金supported by the National Key R&D Program of China(No.2022YFB3504700)the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDA0400304)the Research Fund of Key Laboratory of Rare Earths,Chinese Academy of Sciences(No.E32PF00116).
文摘Hydrogen energy has gained widespread recognition for its environmentally friendly nature,high energy density and abundant resources,making it a promising energy carrier for a sustainable and clean energy society.However,safe and efficient hydrogen storage remains a significant challenge due to its inherent leakiness and flammability.To overcome these challenges,alloys featuring body-centered cubic(BCC)structures have emerged as compelling candidates for hydrogen storage,owing to their exceptional capacity to achieve high-density hydrogen storage up to 3.8 wt%at ambient temperatures.Nonetheless,their practical application faces limited dehydriding capacity,complex activation processes,high costs and poor cyclic stability.Various modification strategies have been explored to overcome these limitations,including lattice regulation,element substitution,rare earth doping and heat treatment.This progress report presents an overview of the previous advancements to enhance five crucial aspects(high-V,medium-V,low-V,V-free and high-entropy alloys)in composition design and hydrogen storage properties within BCC-structured alloys.Subsequently,an in-depth analysis is conducted to examine the relationship between crystal structures and hydrogen storage properties specific to BCC-structured alloys,covering aspects such as composition,crystal structure,hydrogen storage capacity,enthalpy and entropy.Furthermore,this review explores current challenges in this field and outlines directions for future research.These insights provide valuable guidance for the design of innovative and cost-effective hydrogen storage alloys.
基金the financial supports from the National Key Research and Development Program of China(No.2022YFB3707501)the National Natural Science Foundation of China(No.51701083)+2 种基金GDAS’Project of Science and Technology Development,China(Nos.2022GDASZH-2022010103,2022GDASZH-2022010107,2020GDASYL-20200102030)the financial support from the National Natural Science Foundation of China(No.52001137)the Basic and Applied Basic Research Foundation of Guangzhou,China(No.202201010206)。
文摘The equiatomic and equimass TiHfMo,TiHfMoNb and TiHfMoNbZr alloys were prepared,and their microstructure,mechanical properties and bio-corrosion behaviors were systematically investigated.The results demonstrated that all the multi-principal element alloys(MPEAs)had a single BCC phase structure without any intermetallic compounds.Moreover,the Young’s moduli and hardness of the MPEAs were respectively within the range of 95−126 GPa and 5.5−6.4 GPa,respectively.In simulated body fluids,the MPEAs had excellent resistance to chloride ion attack due to the fact that the passive films consisted of multiple oxides and the surface possessed large contact angles.Compared with CP-Ti and Ti6Al4V alloy,equiatomic TiHfMo and TiHfMoNb alloys had a desirable combination of pitting and corrosion resistance,wettability,and wear resistance,and can be utilized as potential candidates for biomedical metallic implants.
基金financially supported by the National Key Research and Development program of China(2022YFB3504700)the National Natural Science Foundation of China(U23A20128)+1 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences(XDA0400304)the Research Projects of Ganjiang Innovation Academy,Chinese Academy of Sciences(No.E355B0020).
文摘Magnesium hydride(MgH_(2))has garnered significant attention as a promising material for high-capacity hydrogen storage.However,its commercial application remains challenging due to the high operating temperature and slow reaction kinetics.In this study,melt-spun Ti_(45)Cr_(40)Nb_(15)(with a BCC phase)hydride(designated as TiCrNbH_(x-)MS)was synthesized and used to form a nano-multiphase composite to improve the de-/rehydrogenation properties of MgH_(2) through ball milling.The incorporation of TiCrNbH_(x-)MS was shown to significantly enhance the hydrogen de-/rehydrogenation properties of MgH_(2).The MgH_(2)+20 wt%TiCrNbH_(x-)MS composite exhibits an appealing initial dehydrogenation temperature of 163℃ and can absorb hydrogen at room temperature.Notably,it releases 5.8 wt% hydrogen in 700 s at 230℃ and recharges 4.3 wt%hydrogen in just 2 mins at 150℃.Even after 100 cycles,it retains a reversible hydrogen capacity of 4.98 wt%.Kinetic analysis revealed that the dehydrogenation rate follows the Chou surface penetration model.Microstructural analysis showed that the FCC phase of the melt-spun TiCrNbH_(x-)MS hydride reversibly transformed into the BCC phase during the de-/rehydrogenation process in the composite.Numerous phase interfaces were generated and uniformly dispersed on the MgH_(2) surface,providing additional hydrogen diffusion pathways and heterogeneous nucleation sites for Mg/MgH_(2),thereby further improving the hydrogen de-/rehydrogenation kinetics of the system.This study offers valuable insights into the use of multiphase composites to enhance MgH_(2) performance.
文摘文章以新疆机场集团为研究对象,选取2013~2023年间的16个机场作为效率分析的目标,运用数据包络分析(DEA)方法,结合BCC模型以及Malmquist指数,从静态和动态两个维度对机场集团的运营效率进行了全面评估。研究结果表明:(1) 乌鲁木齐地窝堡国际机场(URC)和库尔勒机场(KRL)作为核心枢纽,其综合效率、技术效率和规模效率均表现优异。(2) 塔什库尔干机场(HQL)和奇台机场(JBK)等支线机场的效率值较低,表明其在资源配置、技术水平和规模匹配方面存在较大提升空间。(3) 技术进步(TC)是效率提升的主要驱动力,尤其是在博乐机场(BPL)和阿勒泰机场(AAT)中表现显著,而乌鲁木齐地窝堡国际机场(URC)和喀什机场(KHG)的效率下降则可能与规模过大、资源配置不合理或区域经济波动有关。This paper takes Xinjiang Airport Group as the research object, selects 16 airports from 2013 to 2023 as the efficiency analysis targets, uses data enveloping analysis (DEA) method, combines BCC model and Malmquist index, and comprehensively evaluates the operational efficiency of the airport group from both static and dynamic dimensions. The results show that: (1) Urumqi Diwopu International Airport (URC) and Korla Airport (KRL), as the core hubs, have excellent performance in comprehensive efficiency, technical efficiency and scale efficiency. (2) The efficiency values of regional airports such as Tashkourgan Airport (HQL) and Qitai Airport (JBK) are low, indicating that there is a large room for improvement in terms of resource allocation, technical level and scale matching. (3) Technological progress (TC) is the main driving force of efficiency improvement, especially in BPL and Altai Airports (AAT), while the efficiency decline of Urumqi Diwopu International Airport (URC) and Kashgar Airport (KHG) may be related to excessive scale, unreasonable resource allocation or regional economic fluctuations.
文摘Basal cell carcinoma(BCC)is the most prevalent form of skin cancer in the world,primarily affecting sun-exposed areas,including the periocular region.When BCC occurs near the eyes,surgical treatment becomes uniquely complex.Excess excisions may cause detrimental effects to eyelid function and undesirable aesthetic outcomes.Conversely,adequate resection must occur to prevent further disease progression.Mohs micrographic surgery(MMS),a technique offering high remission rates,is often employed for periocular BCC.This method allows for precise cancer removal while preserving as much healthy tissue as possible,balancing the need for both effective treatment and aesthetic and functional preservation.Following Mohs surgery of periocular BCC,reconstruction methods vary and can be tailored based on the size of the resection and the functional requirements of the affected tissue.Amongst these methods,primary closure with and without secondary intentions,direct margin repair,local flap closure and advance flap,Tenzel flap,tarso-conjunctival flap,periocular skin grafting,and structural grafting are commonly utilized and each has its advantages and limitations.In the future,advancements in synthetic flaps and stabilizing glues in the periocular region may provide additional tools for post-Mohs reconstruction.However,these emerging techniques require further research to establish efficacy and safety,especially in more complex and sensitive regions like the periocular tissues.The primary purpose of this review is to provide a comprehensive analysis of periocular reconstructive techniques following Mohs surgery,comparing their efficacy,functional outcomes,and aesthetic considerations while addressing recent advancements such as synthetic flaps and stabilizing glues to guide clinical decision-making.
