Glass-compatible and self-powered temperature alarm system by temperature-responsive organic manganese halides via backward energy transfer process

A pioneering glass-compatible transparent temperature alarm system self-powered by luminescent solar concentrators(LSCs) is reported.Single green-emitted organic manganese halides(OMHs) of PEA_(2)MnBr_(2)I_(2),which has a unique temperature-dependent backward energy transfer process from selftrapped state to^(4)T_(1)energy level of Mn,is used for triggering the temperature alarm.The LSC with redemitted CsPbI_(3)perovskite-polymer composite films on the glass substrate is used for power supply.The spectrally separated nature between the green-emitted OMHs for temperature alarm and red-emitted CsPbI3in LSC for power supply allows for probing the signal light of temperature-responsive OMHs without the interference of LSCs,making it possible to calibrate the temperature visually just by a self-powered brightness detection circuit with LED indicators.Taking advantage of LSC without hot spot effects plaguing the solar cells,as-prepared temperature alarm system can operate well on both sunny and cloudy day.

Damage alarming of long-span suspension bridge based on GPS-RTK monitoring

Structure damage identification and alarming of long-span bridge were conducted with three-dimensional dynamic displacement data collected by GPS subsystem of health monitoring system on Runyang Suspension Bridge.First,the effects of temperature on the main girder spatial position coordinates were analyzed from the transverse,longitudinal and vertical directions of bridge,and the correlation regression models were built between temperature and the position coordinates of main girder in the longitudinal and vertical directions;then the alarming indices of coordinate residuals were conducted,and the mean-value control chart was applied to making statistical pattern identification for abnormal changes of girder dynamic coordinates;and finally,the structural damage alarming method of main girder was established.Analysis results show that temperature has remarkable correlation with position coordinates in the longitudinal and vertical directions of bridge,and has weak correlation with the transverse coordinates.The 3%abnormal change of the longitudinal coordinates and 5%abnormal change of the vertical ones caused by structural damage are respectively identified by the mean-value control chart method based on GPS dynamic monitoring data and hence the structural abnormalities state identification and damage alarming for main girder of long-span suspension bridge can be realized in multiple directions.

Hydrophobic,Hemostatic and Durable Nanofiber Composites with a Screw‑Like Surface Architecture for Multifunctional Sensing Electronics

MXene-decorated textile composites have attracted tremendous attention,due to their possible applications in wearable sensing electronics.However,the easy oxidation,low strain sensitivity and poor water-proof performance restrict the applications of MXene-based smart textiles.Here,we developed a flexible and hydrophobic polymer nanofibrous composite with a screw-like structure by assembling MXene nanosheets onto a prestretched polyurethane(PU)nanofiber surface and subsequent fluorination treatment.The thin hydrophobic fluorosilane layer can greatly prevent the MXene shell from being oxidized and simultaneously endow the nanofiber composite with good hemostatic performance.The wrinkled MXene shell with the screw-like structure enhances the sensitivity of MXene@PU nanofiber composite(HMPU)toward strain,and the hydrophobic strain sensor exhibits a high gauge factor(324.4 in the strain range of 85–100%),and can detect different human movements.In virtue of its excellent water-proof performance,HMPU can function normally in corrosive and underwater conditions.In addition,the resistance of HMPU exhibits a negative temperature coefficient;thus,HMPU shows potential for monitoring temperature and providing a temperature alarm.The multifunctional HMPU shows broad application prospects in smart wearable electronics.