Exploding foil initiator(EFI)is a kind of advanced device for initiating explosives,but its function is unstable when it comes to directly igniting pyrotechnics.To solve the problem,this research aims to reveal the ig...Exploding foil initiator(EFI)is a kind of advanced device for initiating explosives,but its function is unstable when it comes to directly igniting pyrotechnics.To solve the problem,this research aims to reveal the ignition mechanism of EFIs directly igniting pyrotechnics.An oscilloscope,a photon Doppler velocimetry,and a plasma spectrum measurement system were employed to obtain information of electric characteristics,impact pressure,and plasma temperature.The results of the electric characteristics and the impact pressure were inconsistent with ignition results.The only thing that the ignition success tests had in common was that their plasma all had a relatively long period of high-temperature duration(HTD).It eventually concludes that the ignition mechanism in this research is the microconvection heat transfer rather than the shock initiation,which differs from that of exploding foil initiators detonating explosives.Furthermore,the methods for evaluating the ignition success of semiconductor bridge initiators are not entirely applicable to the tests mentioned in this paper.The HTD is the critical parameter for judging the ignition success,and it is influenced by two factors:the late time discharge and the energy of the electric explosion.The longer time of the late time discharge and the more energy of the electric explosion,the easier it is to expand the HTD,which improves the probability of the ignition success.展开更多
Wearable electronics are advancing towards miniaturization and flexibility.However,traditional energy supply methods have largely hindered their development.An effective solution to this problem is to convert human me...Wearable electronics are advancing towards miniaturization and flexibility.However,traditional energy supply methods have largely hindered their development.An effective solution to this problem is to convert human mechanical energy into electricity to power wearable electronic devices.Therefore,it is greatly attractive to design flexible,foldable and even stretchable energy harvesting devices.Herein,we use the electrospinning and kirigami approach to develop a type of highly stretchable kirigami-patterned nanofiber-based triboelectric nanogenerator(K-TENG).Due to its innovative structural design,the K-TENG can achieve a tensile strain of 220%,independent of the tensile properties of the material itself.When a person swings their arms,the K-TENG fixed to the clothing can convert mechanical energy from human movement into electrical energy.The produced electricity can directly drive 50 LED lights and a digital watch,or be stored in a lithium battery to charge the smartwatch and smartphone,respectively.This study employs a new method to fabricate a stretchable triboelectric nanogenerator and demonstrates its promising applications in wearable power technology.展开更多
Textile-based electronic devices have attracted increasing interest in recent years due to their wearability,breathability,comfort.Among them,textile-based triboelectric nanogenerators(T-TENGs)exhibit remarkable advan...Textile-based electronic devices have attracted increasing interest in recent years due to their wearability,breathability,comfort.Among them,textile-based triboelectric nanogenerators(T-TENGs)exhibit remarkable advantages in mechanical energy harvesting and self-powered sensing.However,there are still some key challenges to the development and application of triboelectric fibers(the basic unit of T-TENG).Scalable production and large-scale integration are still significant factors hindering its application.At the same time,there are some difficulties to overcome in the manufacturing process,such as achieving good stretchability and a quick production,overcoming incompatibility between conductive and triboelectric materials.In this study,triboelectric fibers are produced continuously by one-step coaxial wet spinning.They are only 0.18 mm in diameter and consist of liquid metal(LM)core and polyurethane(PU)sheath.Due to the good mechanical properties between them,there is no interface incompatibility of the triboelectric fibers.In addition,triboelectric fibers can be made into large areas of T-TENG by means of digital embroidery and plain weave.The T-TENGs can be used for energy harvesting and self-powered sensing.When they are fixed on the forearm can monitor various strokes in badminton.This work provides a promising strategy for the large-scale fabrication and large-area integration of triboelectric fibers,promotes the development of wearable T-TENGs.展开更多
文摘Exploding foil initiator(EFI)is a kind of advanced device for initiating explosives,but its function is unstable when it comes to directly igniting pyrotechnics.To solve the problem,this research aims to reveal the ignition mechanism of EFIs directly igniting pyrotechnics.An oscilloscope,a photon Doppler velocimetry,and a plasma spectrum measurement system were employed to obtain information of electric characteristics,impact pressure,and plasma temperature.The results of the electric characteristics and the impact pressure were inconsistent with ignition results.The only thing that the ignition success tests had in common was that their plasma all had a relatively long period of high-temperature duration(HTD).It eventually concludes that the ignition mechanism in this research is the microconvection heat transfer rather than the shock initiation,which differs from that of exploding foil initiators detonating explosives.Furthermore,the methods for evaluating the ignition success of semiconductor bridge initiators are not entirely applicable to the tests mentioned in this paper.The HTD is the critical parameter for judging the ignition success,and it is influenced by two factors:the late time discharge and the energy of the electric explosion.The longer time of the late time discharge and the more energy of the electric explosion,the easier it is to expand the HTD,which improves the probability of the ignition success.
基金the China Postdoctoral Science Foundation(Grant No.2023TQ0316)the National Natural Science Foundation of China(Grant No.52273046).
文摘Wearable electronics are advancing towards miniaturization and flexibility.However,traditional energy supply methods have largely hindered their development.An effective solution to this problem is to convert human mechanical energy into electricity to power wearable electronic devices.Therefore,it is greatly attractive to design flexible,foldable and even stretchable energy harvesting devices.Herein,we use the electrospinning and kirigami approach to develop a type of highly stretchable kirigami-patterned nanofiber-based triboelectric nanogenerator(K-TENG).Due to its innovative structural design,the K-TENG can achieve a tensile strain of 220%,independent of the tensile properties of the material itself.When a person swings their arms,the K-TENG fixed to the clothing can convert mechanical energy from human movement into electrical energy.The produced electricity can directly drive 50 LED lights and a digital watch,or be stored in a lithium battery to charge the smartwatch and smartphone,respectively.This study employs a new method to fabricate a stretchable triboelectric nanogenerator and demonstrates its promising applications in wearable power technology.
基金the National Natural Science Foundation of China(No.22109012)Natural Science Foundation of the Beijing Municipality(Nos.L222037 and 2212052)the Fundamental Research Funds for the Central Universities(No.E1E46805).
文摘Textile-based electronic devices have attracted increasing interest in recent years due to their wearability,breathability,comfort.Among them,textile-based triboelectric nanogenerators(T-TENGs)exhibit remarkable advantages in mechanical energy harvesting and self-powered sensing.However,there are still some key challenges to the development and application of triboelectric fibers(the basic unit of T-TENG).Scalable production and large-scale integration are still significant factors hindering its application.At the same time,there are some difficulties to overcome in the manufacturing process,such as achieving good stretchability and a quick production,overcoming incompatibility between conductive and triboelectric materials.In this study,triboelectric fibers are produced continuously by one-step coaxial wet spinning.They are only 0.18 mm in diameter and consist of liquid metal(LM)core and polyurethane(PU)sheath.Due to the good mechanical properties between them,there is no interface incompatibility of the triboelectric fibers.In addition,triboelectric fibers can be made into large areas of T-TENG by means of digital embroidery and plain weave.The T-TENGs can be used for energy harvesting and self-powered sensing.When they are fixed on the forearm can monitor various strokes in badminton.This work provides a promising strategy for the large-scale fabrication and large-area integration of triboelectric fibers,promotes the development of wearable T-TENGs.
