The movement speed of Typhoon In-Fa(2021)was notably slow,at 10 km h-1or less,for over 20 hours following its landfall in Zhejiang,China,in contrast to other typhoons that have made landfall.This study examines the fa...The movement speed of Typhoon In-Fa(2021)was notably slow,at 10 km h-1or less,for over 20 hours following its landfall in Zhejiang,China,in contrast to other typhoons that have made landfall.This study examines the factors contributing to the slow movement of Typhoon In-Fa,including the steering flow,diabatic heating,vertical wind shear(VWS),and surface synoptic situation,by comparing it with Typhoons Yagi(2018)and Rumbia(2018)which followed similar tracks.The findings reveal that the movement speed of Typhoons Yagi and Rumbia is most closely associated with their respective 500 h Pa environmental winds,with a steering flow of 10^(-12)m s^(-1).In contrast,Typhoon InFa’s movement speed is most strongly correlated with the 850 h Pa environmental wind field,with a steering flow speed of only 2 m s^(-1).Furthermore,as Typhoon In-Fa moves northwest after landfall,its intensity is slightly greater than that of Typhoons Yagi and Rumbia,and the pressure gradient in front of Typhoon In-Fa is notably smaller,leading to its slow movement.Additionally,the precipitation distribution of Typhoon In-Fa differs from that of the other two typhoons,resulting in a weak asymmetry of wavenumber-1 diabatic heating,which indirectly affects its movement speed.Further analysis indicates that VWS can alter the typhoon’s structure,weaken its intensity,and ultimately impact its movement.展开更多
A novel melting infiltration by ultrasonic vibration was investigated and applied to fabricate Ti6Al4V(TC4)lattice structure-reinforced Mg-10Gd-2Y-1Zn-xZr(refer to VW92 hereafter,x=0,0.5 wt%)alloy matrix composites.Th...A novel melting infiltration by ultrasonic vibration was investigated and applied to fabricate Ti6Al4V(TC4)lattice structure-reinforced Mg-10Gd-2Y-1Zn-xZr(refer to VW92 hereafter,x=0,0.5 wt%)alloy matrix composites.The edge-to-edge matching model indicates that the well-matching and possible orientation relationships(ORs)between theα-Mg andα-Ti,[10-10]_(α-Mg)//[11-23]_(α-Ti) in(0002)_(α-Mg)//(10-10)_(α-Ti) possesses the smallest misfit of 0.4%(f_(r)),and thus theα-Mg grains can nucleate on the TC4 lattice structure.Interfacial reaction occurred in the TC4/VW92+0.5 wt%Zr composites,and the reaction product was confirmed to be Al_(2)Zr_(3),AlZr_(2) andα-Ti(Zr)particles formed by continuous solution of Zr-Ti.Among the interfacial products,the AlZr_(2) phase is a brittle phase with high-volume fraction,which is not conducive to the load transfer.But generally speaking,theα-Ti(Zr)and theα-Mg tend to form a coherent interface,which is beneficial for improving the interfacial bonding strength of composites.展开更多
基金Natural Science Foundation of Shandong Province(ZR2021MD012)CMA Special Fund for Innovation and Development(CXFZ2023J015)。
文摘The movement speed of Typhoon In-Fa(2021)was notably slow,at 10 km h-1or less,for over 20 hours following its landfall in Zhejiang,China,in contrast to other typhoons that have made landfall.This study examines the factors contributing to the slow movement of Typhoon In-Fa,including the steering flow,diabatic heating,vertical wind shear(VWS),and surface synoptic situation,by comparing it with Typhoons Yagi(2018)and Rumbia(2018)which followed similar tracks.The findings reveal that the movement speed of Typhoons Yagi and Rumbia is most closely associated with their respective 500 h Pa environmental winds,with a steering flow of 10^(-12)m s^(-1).In contrast,Typhoon InFa’s movement speed is most strongly correlated with the 850 h Pa environmental wind field,with a steering flow speed of only 2 m s^(-1).Furthermore,as Typhoon In-Fa moves northwest after landfall,its intensity is slightly greater than that of Typhoons Yagi and Rumbia,and the pressure gradient in front of Typhoon In-Fa is notably smaller,leading to its slow movement.Additionally,the precipitation distribution of Typhoon In-Fa differs from that of the other two typhoons,resulting in a weak asymmetry of wavenumber-1 diabatic heating,which indirectly affects its movement speed.Further analysis indicates that VWS can alter the typhoon’s structure,weaken its intensity,and ultimately impact its movement.
基金supported by the Guangdong Major Project of Basic and Applied Basic Research (2020B0301030006)the National Natural Science Foundation of China (52225101)+2 种基金the Scientific Research Foundation of Chongqing University of Technology (2020ZDZ006)the Science and Technology Research Program of the Chongqing Municipal Education Commission (KJZD-K202201108)the University Innovation Research Group of Chongqing (CXQT20023).
文摘A novel melting infiltration by ultrasonic vibration was investigated and applied to fabricate Ti6Al4V(TC4)lattice structure-reinforced Mg-10Gd-2Y-1Zn-xZr(refer to VW92 hereafter,x=0,0.5 wt%)alloy matrix composites.The edge-to-edge matching model indicates that the well-matching and possible orientation relationships(ORs)between theα-Mg andα-Ti,[10-10]_(α-Mg)//[11-23]_(α-Ti) in(0002)_(α-Mg)//(10-10)_(α-Ti) possesses the smallest misfit of 0.4%(f_(r)),and thus theα-Mg grains can nucleate on the TC4 lattice structure.Interfacial reaction occurred in the TC4/VW92+0.5 wt%Zr composites,and the reaction product was confirmed to be Al_(2)Zr_(3),AlZr_(2) andα-Ti(Zr)particles formed by continuous solution of Zr-Ti.Among the interfacial products,the AlZr_(2) phase is a brittle phase with high-volume fraction,which is not conducive to the load transfer.But generally speaking,theα-Ti(Zr)and theα-Mg tend to form a coherent interface,which is beneficial for improving the interfacial bonding strength of composites.
