At present,phase change materials(PCMs)with single function hardly meet the needs of advanced intelligent materials in practical applications,and the multifunction integration is the current trend.However,photo-cured ...At present,phase change materials(PCMs)with single function hardly meet the needs of advanced intelligent materials in practical applications,and the multifunction integration is the current trend.However,photo-cured multifunctional PCMs are hampered by insufficient transparency due to adding functional fillers,such as carbon and metal materials.The novel strategy is necessary to overcome this limitation.Here,a photo-cured multifunctional PCM is prepared by using the design of a lamellar structure composing the photo-cured phase change polymer layer and the functional fillers layer.The curing of the phase change polymer is realized by the photo-induced"thiol-ene"click reaction,and reversible dynamic disulfide bonds are introduced into the PCM,which not only gives the phase change crosslinked network reprocessability,but also strengthens the interface layer by the chain rearrangement to form a stable composite structure.The carboxylated multiwalled carbon nanotubes(CCNTs)and silver nanowires(AgNWs),as functional fillers,give the PCM photo-thermal conversion,self-cleaning and electromagnetic shielding(EMI SE)performances.Its phase change latent heat and photo-thermal conversion can reach 105.2 J/g and 78.5%,and the water contact angle is 142°with self-cleaning performance.In addition,due to the dense and well-developed conductive path formed by AgNWs layer on the PCM surface,the EMI SE effect can reach 39 dB with only 6.3%(in mass)filler content and 7.2%phase change latent heat loss.As far as we know,this is the first report about photo-cured PCMs with self-cleaning,photo-thermal conversion and EMI SE performances.展开更多
Pulsed eddy current （PEC） non-destructive test- ing and evaluation （NDT＆E） has been around for some time and it is still attracting extensive attention from researchers around the globe, which can be witnessed th...Pulsed eddy current （PEC） non-destructive test- ing and evaluation （NDT＆E） has been around for some time and it is still attracting extensive attention from researchers around the globe, which can be witnessed through the reports reviewed in this paper. Thanks to its richness of spectral components, various applications of this technique have been proposed and reported in the lit- erature covering both structural integrity inspection and material characterization in various industrial sectors. To support its development and for better understanding of the phenomena around the transient induced eddy currents, attempts for its modelling both analytically and numeri- cally have been made by researchers around the world. This review is an attempt to capture the state-of-the-art development and applications of PEC, especially in the last 15 years and it is not intended to be exhaustive. Future challenges and opportunities for PEC NDT＆E are also presented.展开更多
Taking into account the nonlinearity of vehicle dynamics and the variations of vehicle parameters,the integrated control strategy for active front steering(AFS)and direct yaw control(DYC)that can maintain the performa...Taking into account the nonlinearity of vehicle dynamics and the variations of vehicle parameters,the integrated control strategy for active front steering(AFS)and direct yaw control(DYC)that can maintain the performance and robustness is a key issue to be researched.Currently,the H∞method is widely applied to the integrated control of chassis dynamics,but it always sacrifices the performance in order to enhance the stability.The modified structure internal model robust control(MSIMC)obtained by modifying internal model control(IMC)structure is proposed for the integrated control of AFS and DYC to surmount the conflict between performance and robustness.Double lane change(DLC)simulation is developed to compare the performance and the stability of the MSIMC strategy,the PID controller based on the reference vehicle model and the H∞controller.Simulation results show that the PID controller may oscillate and go into instability in severe driving conditions because of large variations of tire parameters,the H∞controller sacrifices the performance in order to enhance the stability,and only the MSIMC controller can both ensure the robustness and the high performance of the integrated control of AFS and DYC.展开更多
文摘At present,phase change materials(PCMs)with single function hardly meet the needs of advanced intelligent materials in practical applications,and the multifunction integration is the current trend.However,photo-cured multifunctional PCMs are hampered by insufficient transparency due to adding functional fillers,such as carbon and metal materials.The novel strategy is necessary to overcome this limitation.Here,a photo-cured multifunctional PCM is prepared by using the design of a lamellar structure composing the photo-cured phase change polymer layer and the functional fillers layer.The curing of the phase change polymer is realized by the photo-induced"thiol-ene"click reaction,and reversible dynamic disulfide bonds are introduced into the PCM,which not only gives the phase change crosslinked network reprocessability,but also strengthens the interface layer by the chain rearrangement to form a stable composite structure.The carboxylated multiwalled carbon nanotubes(CCNTs)and silver nanowires(AgNWs),as functional fillers,give the PCM photo-thermal conversion,self-cleaning and electromagnetic shielding(EMI SE)performances.Its phase change latent heat and photo-thermal conversion can reach 105.2 J/g and 78.5%,and the water contact angle is 142°with self-cleaning performance.In addition,due to the dense and well-developed conductive path formed by AgNWs layer on the PCM surface,the EMI SE effect can reach 39 dB with only 6.3%(in mass)filler content and 7.2%phase change latent heat loss.As far as we know,this is the first report about photo-cured PCMs with self-cleaning,photo-thermal conversion and EMI SE performances.
基金Ministry of Higher Education of Malaysia for funding the project on PEC NDT at IIUM through the research grant FRGS16-059-0558supported by the National Natural Science Foundation of China under research grants 51677187 and 51307172
文摘Pulsed eddy current （PEC） non-destructive test- ing and evaluation （NDT＆E） has been around for some time and it is still attracting extensive attention from researchers around the globe, which can be witnessed through the reports reviewed in this paper. Thanks to its richness of spectral components, various applications of this technique have been proposed and reported in the lit- erature covering both structural integrity inspection and material characterization in various industrial sectors. To support its development and for better understanding of the phenomena around the transient induced eddy currents, attempts for its modelling both analytically and numeri- cally have been made by researchers around the world. This review is an attempt to capture the state-of-the-art development and applications of PEC, especially in the last 15 years and it is not intended to be exhaustive. Future challenges and opportunities for PEC NDT＆E are also presented.
基金supported by the National Natural Science Foundation of China(Grant No.51375009 and 11072106)
文摘Taking into account the nonlinearity of vehicle dynamics and the variations of vehicle parameters,the integrated control strategy for active front steering(AFS)and direct yaw control(DYC)that can maintain the performance and robustness is a key issue to be researched.Currently,the H∞method is widely applied to the integrated control of chassis dynamics,but it always sacrifices the performance in order to enhance the stability.The modified structure internal model robust control(MSIMC)obtained by modifying internal model control(IMC)structure is proposed for the integrated control of AFS and DYC to surmount the conflict between performance and robustness.Double lane change(DLC)simulation is developed to compare the performance and the stability of the MSIMC strategy,the PID controller based on the reference vehicle model and the H∞controller.Simulation results show that the PID controller may oscillate and go into instability in severe driving conditions because of large variations of tire parameters,the H∞controller sacrifices the performance in order to enhance the stability,and only the MSIMC controller can both ensure the robustness and the high performance of the integrated control of AFS and DYC.
