Multi-layer riveted structures are widely applied to aircraft.During the service,cracks may appear within these structures due to stress concentration of the riveted holes.The guided wave monitoring has been proved to...Multi-layer riveted structures are widely applied to aircraft.During the service,cracks may appear within these structures due to stress concentration of the riveted holes.The guided wave monitoring has been proved to be an effective tool to deal with this problem.However,there is a lack of understanding of the wave propagation process across such kinds of structures.This study proposes a piezoelectric guided wave simulation method to reveal the propagation of guided waves in multi-layer riveted structures.Effects of pretension force,friction coefficient,and cracks that might influence wave characteristics are studied.The guided wave simulation data is compared with the experimental results and the results verify the simulation model.Then the guided wave propagation in a more complex long-beam butt joint structure is further simulated.展开更多
The development of high-energy-density Na-ion batteries(SIBs)is hindered by the lack of a high-capacity anode with fast Na-ion reaction kinetics due to the large Na^(+)radius and slow Na^(+)diffusion kinetics.Herein,a...The development of high-energy-density Na-ion batteries(SIBs)is hindered by the lack of a high-capacity anode with fast Na-ion reaction kinetics due to the large Na^(+)radius and slow Na^(+)diffusion kinetics.Herein,a high specific capacity anode is designed by constructing a double vanadium-based compound(VS_(4)–V_(2)CT_(x))heterostructure composite.The strong rivet structure bridged according to the S–V–C bonding interaction between VS_(4) and V_(2)CT_(x) unblocks the three-dimensional channel of electron transport and synergistically promotes ion diffusion and charge transport.In addition,the electrochemical reaction kinetics can be enhanced by adjusting the ratio of the vanadium valence state to facilitate electrocatalytic activity at the VS_(4)–V_(2)CT_(x) heterojunction interface.When used as a SIB anode,the VS_(4)–V_(2)CT_(x) composite exhibits excellent ultra-long cycling performance,with a specific discharge capacity of 322 mA h g^(−1) after 4000 cycles at a large current density of 10 A g^(−1).All-vanadium SIBs(Na_(3)V_(2)(PO_(4))_(3)@C//VS_(4)–V_(2)CT_(x))are also assembled and showed excellent sodium storage performance with a high reversible capacity of 234 mA h g^(−1) at 3 A g^(−1),indicating broad application prospects for vanadium-based sodium storage devices.展开更多
文摘Multi-layer riveted structures are widely applied to aircraft.During the service,cracks may appear within these structures due to stress concentration of the riveted holes.The guided wave monitoring has been proved to be an effective tool to deal with this problem.However,there is a lack of understanding of the wave propagation process across such kinds of structures.This study proposes a piezoelectric guided wave simulation method to reveal the propagation of guided waves in multi-layer riveted structures.Effects of pretension force,friction coefficient,and cracks that might influence wave characteristics are studied.The guided wave simulation data is compared with the experimental results and the results verify the simulation model.Then the guided wave propagation in a more complex long-beam butt joint structure is further simulated.
基金supported by the National Natural Science Foundation of China(Grant No.52072322,51604250)the Sichuan Science and Technology Program(No.2022YFG0294,2019-GH02-00052-HZ).
文摘The development of high-energy-density Na-ion batteries(SIBs)is hindered by the lack of a high-capacity anode with fast Na-ion reaction kinetics due to the large Na^(+)radius and slow Na^(+)diffusion kinetics.Herein,a high specific capacity anode is designed by constructing a double vanadium-based compound(VS_(4)–V_(2)CT_(x))heterostructure composite.The strong rivet structure bridged according to the S–V–C bonding interaction between VS_(4) and V_(2)CT_(x) unblocks the three-dimensional channel of electron transport and synergistically promotes ion diffusion and charge transport.In addition,the electrochemical reaction kinetics can be enhanced by adjusting the ratio of the vanadium valence state to facilitate electrocatalytic activity at the VS_(4)–V_(2)CT_(x) heterojunction interface.When used as a SIB anode,the VS_(4)–V_(2)CT_(x) composite exhibits excellent ultra-long cycling performance,with a specific discharge capacity of 322 mA h g^(−1) after 4000 cycles at a large current density of 10 A g^(−1).All-vanadium SIBs(Na_(3)V_(2)(PO_(4))_(3)@C//VS_(4)–V_(2)CT_(x))are also assembled and showed excellent sodium storage performance with a high reversible capacity of 234 mA h g^(−1) at 3 A g^(−1),indicating broad application prospects for vanadium-based sodium storage devices.
