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As an epoch of intelligent clothing is coming, soft body armor is required to possess not only improved mechanical performance but more functions, such as electronic conductivity, anti-ultraviolet capability, electrical heating property, etc. In this work, polypyrrole (PPy) is coated on Twaron fabrics to enhancing their stabbing resistance and simultaneously endowing them with multifunction. The resultant PPy-coated Twaron fabric exhibits better tensile strength. The strength of the PPy-coated fiber is increased by 12.03% and the maximum friction between the yarns in the PPy-coated fabric increases by 8.96 times. The quasi-static stab resistance of the PPy-coated fabric is also significantly improved in comparison with that of the neat counterpart. Furthermore, PPy-coated fabric exhibits anti-ultraviolet capability, high electrical conductivity, and stable electrical heating properties. The saturation temperature from the electrical heating is tunable by adjusting the applied voltage. These functions ensure that the treated fabrics can be applied in more areas and facilitate relieving the adverse effects from the external environment (rainstorm, blizzard, insolation, etc.) for the soft body armor. This study offers the potential of developing the novel generation of smart soft body armor with both excellent protective performance and intelligent wearable properties. [ABSTRACT FROM AUTHOR]

The co‐insertion of dual ions can often offer enhanced electrochemical performance for the aqueous zinc batteries. Although the insertion of non‐metallic ions has been achieved in aqueous zinc batteries, the co‐insertion chemistry of non‐metallic cations is still a challenge. Here, a reversible H+/NH4+ co‐insertion/extraction mechanism was developed in an aqueous Zn/MnO2 battery system. The synergistic effect between the dual cations endows the aqueous batteries with the fast kinetics of ion diffusion and the reversible structure evolution of MnO2. As a result, the Zn/MnO2 battery displays excellent rate capability and cycling performance. This work will pave the way toward the design of aqueous rechargeable batteries with non‐metallic ions. [ABSTRACT FROM AUTHOR]

Metallic zinc is a promising anode candidate of aqueous zinc‐ion batteries owing to its high theoretical capacity and low redox potential. However, Zn anodes usually suffer from dendrite and side reactions, which will degrade their cycle stability and reversibility. Herein, we developed an in situ spontaneously reducing/assembling strategy to assemble a ultrathin and uniform MXene layer on the surface of Zn anodes. The MXene layer endows the Zn anode with a lower Zn nucleation energy barrier and a more uniformly distributed electric field through the favorable charge redistribution effect in comparison with pure Zn. Therefore, MXene‐integrated Zn anode exhibits obviously low voltage hysteresis and excellent cycling stability with dendrite‐free behaviors, ensuring the high capacity retention and low polarization potential in zinc‐ion batteries. [ABSTRACT FROM AUTHOR]

The electrochemical performance of vanadium‐oxide‐based cathodes in aqueous zinc‐ion batteries (ZIBs) depends on their degree of crystallinity and composite state with carbon materials. An in situ electrochemical induction strategy was developed to fabricate a metal–organic‐framework‐derived composite of amorphous V2O5 and carbon materials (a‐V2O5@C) for the first time, where V2O5 is in an amorphous state and uniformly distributed in the carbon framework. The amorphous structure endows V2O5 with more isotropic Zn2+ diffusion routes and active sites, resulting in fast Zn2+ transport and high specific capacity. The porous carbon framework provides a continuous electron transport pathway and ion diffusion channels. As a result, the a‐V2O5@C composites display extraordinary electrochemical performance. This work will pave the way toward design of ZIB cathodes with superior rate performance. [ABSTRACT FROM AUTHOR]

In finite element (FE) modelling of ballistic performance of fabric, shear moduli of continuous yarn models are usually specified based on approximations and assumptions, despite their significant influence on energy absorption and yarn failure time in a ballistic impact event. This paper applies reverse engineering method for estimating shear modulus G 13 of a continuous multifilament yarn model for simulating the ballistic behaviour of the yarn or its fabric. A ballistic event of Dyneema® SK65 yarn model impacted by a projectile travelling at 477 m/s is used to illustrate the establishment of the methodology. The procedure starts by relating G 13 and transverse wave velocity (u t) through regression whose correlation factor R2 is 0.999. u t is calculated by the classical Smith equations. The regressed relation and the availability of u t value enable the calculation of G 13. The simulated results of the Dyneema® yarn model with such estimated G 13 show healthy agreements to the analytical and experimental counterparts in terms of u t and the slope angle of fabric deflection θ. The reverse engineering method has been used for obtaining G 13 successfully for yarn models of other materials, e.g. Kevlar KM2 and Zylon®, in simulating their transverse deflection behaviour under the ballistic impact. [ABSTRACT FROM AUTHOR]

The co-insertion of dual ions can often offer enhanced electrochemical performance for the aqueous zinc batteries. Although the insertion of non-metallic ions has been achieved in aqueous zinc batteries, the co-insertion chemistry of non-metallic cations is still a challenge. Here, a reversible H + /NH 4 + co-insertion/extraction mechanism was developed in an aqueous Zn/MnO 2 battery system. The synergistic effect between the dual cations endows the aqueous batteries with the fast kinetics of ion diffusion and the reversible structure evolution of MnO 2 . As a result, the Zn/MnO 2 battery displays excellent rate capability and cycling performance. This work will pave the way toward the design of aqueous rechargeable batteries with non-metallic ions., (© 2021 Wiley-VCH GmbH.)

The electrochemical performance of vanadium-oxide-based cathodes in aqueous zinc-ion batteries (ZIBs) depends on their degree of crystallinity and composite state with carbon materials. An in situ electrochemical induction strategy was developed to fabricate a metal-organic-framework-derived composite of amorphous V 2 O 5 and carbon materials (a-V 2 O 5 @C) for the first time, where V 2 O 5 is in an amorphous state and uniformly distributed in the carbon framework. The amorphous structure endows V 2 O 5 with more isotropic Zn 2+ diffusion routes and active sites, resulting in fast Zn 2+ transport and high specific capacity. The porous carbon framework provides a continuous electron transport pathway and ion diffusion channels. As a result, the a-V 2 O 5 @C composites display extraordinary electrochemical performance. This work will pave the way toward design of ZIB cathodes with superior rate performance., (© 2020 Wiley-VCH GmbH.)