Metal halide perovskites(MHPs)are an emerging class of semiconductors that have demonstrated their promise at various energy frontiers.Especially,perovskite-based solar cells(PSCs)are considered as a disruptive photov...Metal halide perovskites(MHPs)are an emerging class of semiconductors that have demonstrated their promise at various energy frontiers.Especially,perovskite-based solar cells(PSCs)are considered as a disruptive photovoltaic technology with their power conversion efficiency rapidly climbing to certified 25.7%[1].展开更多
Recent advances in bone regeneration have introduced the concept of four-dimensional(4D)scaffolds that can undergo morphological and functional changes in response to external stimuli.While several studies have propos...Recent advances in bone regeneration have introduced the concept of four-dimensional(4D)scaffolds that can undergo morphological and functional changes in response to external stimuli.While several studies have proposed patient-specific designs for defect sites,they often fail to adequately distinguish the advantages of 4D scaffolds over conventional 3D counterparts.This study aimed to investigate the potential benefits of 4D scaffolds in clinically challenging scenarios involving curved defects,where fixation is difficult.We proposed the use of Shape-Memory Polymers(SMPs)as a solution to address critical issues in personalized scaffold fabrication,including dimensional accuracy,measurement error,and manufacturing imprecision.Experimental results demonstrated that the Curved-Layer Fused Deposition Modeling(CLFDM)scaffold,which offers superior conformability to curved defects,achieved significantly higher interfacial contact with the defect area compared to traditional Fused Deposition Modeling(FDM)scaffolds.Specifically,the CLFDM scaffold facilitated bone regeneration of 25.59±4.72 mm^(3),which is more than twice the 9.37±1.36 mm^(3)observed with the 3D FDM scaffold.Furthermore,the 4D CLFDM scaffold achieved 75.38±11.65 mm^(3)of new bone formation after four weeks,approximately three times greater than that of the 3D CLFDM scaffold,regardless of surface micro-roughness.These results underscore that improved geometrical conformity between the scaffold and the defect site enhances cellular infiltration and contributes to more effective bone regeneration.The findings also highlight the promise of 4D scaffolds as a compelling strategy to overcome geometric and dimensional mismatches in the design of patient-specific scaffolds.展开更多
To elucidate the underlying corrosion mechanism of selective laser melting(SLM)WE43 alloys,a detailed comparative analysis was conducted on the micro structure and corrosion behavior of WE43 Mg alloy in extruded,SLM,a...To elucidate the underlying corrosion mechanism of selective laser melting(SLM)WE43 alloys,a detailed comparative analysis was conducted on the micro structure and corrosion behavior of WE43 Mg alloy in extruded,SLM,and solution-treated states.The SLM WE43 alloy exhibits a mixed grain micro structure composed of columnar and equiaxed grains,with an average grain size of 3.64μm.Secondary phases are continuously distributed along melt track boundaries,and the dislocation density reaches up to 2.55 x 1014 m-2.SLM WE43 alloy,with a relative density of 99.47%,demonstrates the highest corrosion rate of 59.26 mm year-1,which decreases to 24.33 mm year-1 after solution treatment.In contrast,the extruded WE43 alloy exhibits the lowest corrosion rate of 6.26 mm year-1.While the extruded and solution-treated WE43 alloys primarily undergo pitting corrosion,the SLM WE43 alloy experiences 3D spatial corrosion due to microgalvanic corrosion of the secondary phases,high dislocation density,and rapid Cl-propagation in 3D defects,characterized by the corrosion products peeling off in successive layers.The study of the 3D spatial corrosion behavior of SLM WE43 alloy offers key insights into the rapid corrosion mechanisms of SLM-produced magnesium alloys.展开更多
基金startup grants,Initiation Grant-Faculty Niche Research Areas(IG-FNRA)2020/21Interdisciplinary Matching Scheme 2020/21 of the Hong Kong Baptist University(HKBU)+1 种基金the Early Career Scheme(No.22300221)from the Hong Kong Research Grant Councilthe support of the Hong Kong Ph.D.Fellowship Scheme。
文摘Metal halide perovskites(MHPs)are an emerging class of semiconductors that have demonstrated their promise at various energy frontiers.Especially,perovskite-based solar cells(PSCs)are considered as a disruptive photovoltaic technology with their power conversion efficiency rapidly climbing to certified 25.7%[1].
基金supported by the National Research Foundation of Korea(NRF)grant funded by the Korean government(MSIT)(No.NRF-2022R1A4A1028747 and RS-2024-00344151).
文摘Recent advances in bone regeneration have introduced the concept of four-dimensional(4D)scaffolds that can undergo morphological and functional changes in response to external stimuli.While several studies have proposed patient-specific designs for defect sites,they often fail to adequately distinguish the advantages of 4D scaffolds over conventional 3D counterparts.This study aimed to investigate the potential benefits of 4D scaffolds in clinically challenging scenarios involving curved defects,where fixation is difficult.We proposed the use of Shape-Memory Polymers(SMPs)as a solution to address critical issues in personalized scaffold fabrication,including dimensional accuracy,measurement error,and manufacturing imprecision.Experimental results demonstrated that the Curved-Layer Fused Deposition Modeling(CLFDM)scaffold,which offers superior conformability to curved defects,achieved significantly higher interfacial contact with the defect area compared to traditional Fused Deposition Modeling(FDM)scaffolds.Specifically,the CLFDM scaffold facilitated bone regeneration of 25.59±4.72 mm^(3),which is more than twice the 9.37±1.36 mm^(3)observed with the 3D FDM scaffold.Furthermore,the 4D CLFDM scaffold achieved 75.38±11.65 mm^(3)of new bone formation after four weeks,approximately three times greater than that of the 3D CLFDM scaffold,regardless of surface micro-roughness.These results underscore that improved geometrical conformity between the scaffold and the defect site enhances cellular infiltration and contributes to more effective bone regeneration.The findings also highlight the promise of 4D scaffolds as a compelling strategy to overcome geometric and dimensional mismatches in the design of patient-specific scaffolds.
基金financially supported by the National Key Research and Development Program of China(No.2022YFC2406000)the National Natural Science Foundation of China(No.52375370)+6 种基金Guangdong Provincial Key R&D Program(No.2023B0909020004)Guangdong Basic and Applied Basic Research Foundation(Nos.2024A1515011024 and 2022B1515250004)Guangzhou Science and Technology Project(No.2024A04J4943)Guangdong Academy of Sciences Development Special Fund Project(No.2022GDASZH-2022010107)Guangdong province Science and Technology Plan Projects(Nos.2023B1212120008,2023B1212060045)Special Support Foundation of Guangdong Province(No.2023TQ07Z559)Shanxi Zhejiang University New Materials and Chemical Research Institute scientific research project(No.2022SX-TD025)
文摘To elucidate the underlying corrosion mechanism of selective laser melting(SLM)WE43 alloys,a detailed comparative analysis was conducted on the micro structure and corrosion behavior of WE43 Mg alloy in extruded,SLM,and solution-treated states.The SLM WE43 alloy exhibits a mixed grain micro structure composed of columnar and equiaxed grains,with an average grain size of 3.64μm.Secondary phases are continuously distributed along melt track boundaries,and the dislocation density reaches up to 2.55 x 1014 m-2.SLM WE43 alloy,with a relative density of 99.47%,demonstrates the highest corrosion rate of 59.26 mm year-1,which decreases to 24.33 mm year-1 after solution treatment.In contrast,the extruded WE43 alloy exhibits the lowest corrosion rate of 6.26 mm year-1.While the extruded and solution-treated WE43 alloys primarily undergo pitting corrosion,the SLM WE43 alloy experiences 3D spatial corrosion due to microgalvanic corrosion of the secondary phases,high dislocation density,and rapid Cl-propagation in 3D defects,characterized by the corrosion products peeling off in successive layers.The study of the 3D spatial corrosion behavior of SLM WE43 alloy offers key insights into the rapid corrosion mechanisms of SLM-produced magnesium alloys.
