Vanadium pentoxide(V_(2)O_(5))displays the characteristics of high theoretical specific capacity,high operating voltage,and adjustable layered structure,possessing the considerable potential as cathode in magnesium me...Vanadium pentoxide(V_(2)O_(5))displays the characteristics of high theoretical specific capacity,high operating voltage,and adjustable layered structure,possessing the considerable potential as cathode in magnesium metal batteries(MMBs).Nevertheless,the large charge-radius ratio of Mg^(2+)induces the strong interactions of Mg^(2+)with solvent molecules of electrolyte and anionic framework of cathode,resulting in a notable voltage polarization and structural deterioration during cycling process.Herein,an in-situ multi-scale structural engineering is proposed to activate the interlayer-expanded V_(2)O_(5)cathode(pillared by tetrabutylammonium cation)via adding hexadecyltrimethylammonium bromide(CTAB)additive into electrolyte.During cycling,the in-situ incorporation of CTA^(+)not only enhances the electrostatic shielding effect and Mg species migration,but also stabilizes the interlayer spacing.Besides,CTA^(+)is prone to be adsorbed on cathode surface and induces the loss-free pulverization and amorphization of electroactive grains,leading to the pronounced effect of intercalation pseudocapacitance.CTAB additive also enables to scissor the Mg^(2+)solvation sheath and tailor the insertion mode of Mg species,further endowing V_(2)O_(5)cathode with fast reaction kinetics.Based on these merits,the corresponding V2O5‖Mg full cells exhibit the remarkable rate performance with capacities as high as 317.6,274.4,201.1,and 132.7 mAh g^(-1)at the high current densities of 0.1,0.2,0.5,and 1 A g^(-1),respectively.Moreover,after 1000 cycles,the capacity is still preserved to be 90,4 mAh g^(-1)at 1 A g^(-1)with an average coulombic efficiency of~100%.Our strategy of synergetic modulations of cathode host and electrolyte solvation structures provides new guidance for the development of high-rate,large-capacity,and long-life MMBs.展开更多
Interacting with digital contents in 3 D is an essential task in various applications such as modeling packages, gaming, virtual reality, etc. Traditional interfaces using keyboard and mouse or trackball usually requi...Interacting with digital contents in 3 D is an essential task in various applications such as modeling packages, gaming, virtual reality, etc. Traditional interfaces using keyboard and mouse or trackball usually require a non-trivial amount of working space as well as a learning process. We present the design of EZ-Manipulator, a new 3 D manipulation interface using smartphones that supports mobile, fast, and ambiguity-free interaction with 3 D objects. Our system leverages the built-in multi-touch input and gyroscope sensor of smartphones to achieve 9 degrees-of-freedom axis-constrained manipulation and free-form rotation.Using EZ-Manipulator to manipulate objects in 3 D is easy. The user merely has to perform intuitive singleor two-finger gestures and rotate the hand-held device to perform manipulations at fine-grained and coarse levels respectively. We further investigate the ambiguity in manipulation introduced by indirect manipulations using a multi-touch interface, and propose a dynamic virtual camera adjustment to effectively resolve the ambiguity. A preliminary study shows that our system has significant lower task completion time compared to conventional use of a keyboard–mouse interface, and provides a positive user experience to both novices and experts.展开更多
基金supported by the National Natural Science Foundation of China(52372249)support by the Program of Shanghai Academic Research Leader(21XD1424400)。
文摘Vanadium pentoxide(V_(2)O_(5))displays the characteristics of high theoretical specific capacity,high operating voltage,and adjustable layered structure,possessing the considerable potential as cathode in magnesium metal batteries(MMBs).Nevertheless,the large charge-radius ratio of Mg^(2+)induces the strong interactions of Mg^(2+)with solvent molecules of electrolyte and anionic framework of cathode,resulting in a notable voltage polarization and structural deterioration during cycling process.Herein,an in-situ multi-scale structural engineering is proposed to activate the interlayer-expanded V_(2)O_(5)cathode(pillared by tetrabutylammonium cation)via adding hexadecyltrimethylammonium bromide(CTAB)additive into electrolyte.During cycling,the in-situ incorporation of CTA^(+)not only enhances the electrostatic shielding effect and Mg species migration,but also stabilizes the interlayer spacing.Besides,CTA^(+)is prone to be adsorbed on cathode surface and induces the loss-free pulverization and amorphization of electroactive grains,leading to the pronounced effect of intercalation pseudocapacitance.CTAB additive also enables to scissor the Mg^(2+)solvation sheath and tailor the insertion mode of Mg species,further endowing V_(2)O_(5)cathode with fast reaction kinetics.Based on these merits,the corresponding V2O5‖Mg full cells exhibit the remarkable rate performance with capacities as high as 317.6,274.4,201.1,and 132.7 mAh g^(-1)at the high current densities of 0.1,0.2,0.5,and 1 A g^(-1),respectively.Moreover,after 1000 cycles,the capacity is still preserved to be 90,4 mAh g^(-1)at 1 A g^(-1)with an average coulombic efficiency of~100%.Our strategy of synergetic modulations of cathode host and electrolyte solvation structures provides new guidance for the development of high-rate,large-capacity,and long-life MMBs.
文摘Interacting with digital contents in 3 D is an essential task in various applications such as modeling packages, gaming, virtual reality, etc. Traditional interfaces using keyboard and mouse or trackball usually require a non-trivial amount of working space as well as a learning process. We present the design of EZ-Manipulator, a new 3 D manipulation interface using smartphones that supports mobile, fast, and ambiguity-free interaction with 3 D objects. Our system leverages the built-in multi-touch input and gyroscope sensor of smartphones to achieve 9 degrees-of-freedom axis-constrained manipulation and free-form rotation.Using EZ-Manipulator to manipulate objects in 3 D is easy. The user merely has to perform intuitive singleor two-finger gestures and rotate the hand-held device to perform manipulations at fine-grained and coarse levels respectively. We further investigate the ambiguity in manipulation introduced by indirect manipulations using a multi-touch interface, and propose a dynamic virtual camera adjustment to effectively resolve the ambiguity. A preliminary study shows that our system has significant lower task completion time compared to conventional use of a keyboard–mouse interface, and provides a positive user experience to both novices and experts.