The development of high-voltage tandem thin-film supercapacitors(TFSCs)has been limited by the issues such as expensive electrode materials,indispensable commercial separators and metal current collectors,and complex ...The development of high-voltage tandem thin-film supercapacitors(TFSCs)has been limited by the issues such as expensive electrode materials,indispensable commercial separators and metal current collectors,and complex manufacturing processes.Herein,we develop a potentially scalable approach to address all these issues by using CO_(2) laser pyrolysis of polyimide(PI)paper into the three-dimensional(3D)morphology of graphene paper in air.The formation process and mechanism of PI to graphene were clarified by microstructure and chemical characterizations and reaction molecular dynamics.The influences of laser scan density,power,defocus,and scan speed on the sheet resistance,longitudinal resistance,Raman spectra,and electrochemical performance of graphene papers were systematically investigated.Results indicate that high-quality graphene papers with ultralow sheet resistance(4.88Ω·square^(-1))and longitudinal resistance(3.46Ω)and extra-large crystalline size(96.1 nm)were achieved under optimized process parameters.The graphene papers can simultaneously serve as active electrode materials,current collectors,and interconnectors.The active area of electrodes is defined by a PI mask,with the help of which a hydrogel electrolyte functions as a separator.The assembled graphene paper-based TFSCs demonstrate outstanding electrochemical performance and mechanical flexibility,with the areal capacitance of 54.5 mF·cm^(-2),energy density of 10.9µWh·cm^(-2),and cycle stability retention of 86.9%over 15000 cycles.Moreover,all the tandem metal-free TFSCs,ranging from 1 to 160 cells,show excellent performance uniformity.The output voltage increases linearly from 1.2 V to 200 V.Significantly,the 160-tandem TFSCs exhibit a high voltage density within a compact volume of∼3.8 cm^(3).This work provides an avenue for achieving tandem metal-free TFSCs in a simple and efficient manner.展开更多
Cleft lip and/or palate(CLP)are the most common craniofacial malformations in humans.Speech problems often persist even after cleft repair,such that follow-up articulation training is usually required.However,the neur...Cleft lip and/or palate(CLP)are the most common craniofacial malformations in humans.Speech problems often persist even after cleft repair,such that follow-up articulation training is usually required.However,the neural mechanism behind effective articulation training remains largely unknown.We used fMRI to investigate the differences in brain activation,functional connectivity,and effective connectivity across CLP patients with and without articulation training and matched normal participants.We found that training promoted task-related brain activation among the articulation-related brain networks,as well as the global attributes and nodal efficiency in the functional-connectivity-based graph of the network.Our results reveal the neural correlates of effective articulation training in CLP patients,and this could contribute to the future improvement of the post-repair articulation training program.展开更多
基金funded by the National Natural Science Foundation of China(Grant Nos.52205457 and 52422511)the National Key R&D Program of China(Grant No.2022YFB4701000)+3 种基金the Guangdong Basic and Applied Basic Research Foundation,China(Grant Nos.2024A1515010043,2025A1515010890 and 2022B1515120011)the Young Talent Support Project of Guangzhou Association for Science and Technology(Grant No.QT2024-010)the Guangzhou Basic and Applied Basic Research Foundation(Grant No.SL2024A04J01501)the State Key Laboratory of Precision Electronic Manufacturing Technology and Equipment(Grant No.JMDZ202303).
文摘The development of high-voltage tandem thin-film supercapacitors(TFSCs)has been limited by the issues such as expensive electrode materials,indispensable commercial separators and metal current collectors,and complex manufacturing processes.Herein,we develop a potentially scalable approach to address all these issues by using CO_(2) laser pyrolysis of polyimide(PI)paper into the three-dimensional(3D)morphology of graphene paper in air.The formation process and mechanism of PI to graphene were clarified by microstructure and chemical characterizations and reaction molecular dynamics.The influences of laser scan density,power,defocus,and scan speed on the sheet resistance,longitudinal resistance,Raman spectra,and electrochemical performance of graphene papers were systematically investigated.Results indicate that high-quality graphene papers with ultralow sheet resistance(4.88Ω·square^(-1))and longitudinal resistance(3.46Ω)and extra-large crystalline size(96.1 nm)were achieved under optimized process parameters.The graphene papers can simultaneously serve as active electrode materials,current collectors,and interconnectors.The active area of electrodes is defined by a PI mask,with the help of which a hydrogel electrolyte functions as a separator.The assembled graphene paper-based TFSCs demonstrate outstanding electrochemical performance and mechanical flexibility,with the areal capacitance of 54.5 mF·cm^(-2),energy density of 10.9µWh·cm^(-2),and cycle stability retention of 86.9%over 15000 cycles.Moreover,all the tandem metal-free TFSCs,ranging from 1 to 160 cells,show excellent performance uniformity.The output voltage increases linearly from 1.2 V to 200 V.Significantly,the 160-tandem TFSCs exhibit a high voltage density within a compact volume of∼3.8 cm^(3).This work provides an avenue for achieving tandem metal-free TFSCs in a simple and efficient manner.
基金We are grateful to all the patients and healthy controls for their generous participation in this study.This work was supported by grants from the National Natural Science Foundation of China(81771909,61701323,and 62171300)the Discipline Construction Foundation of Beijing Stomatological Hospital(19-09-24)+1 种基金the Capital Medical University Research and Development Fund(PYZ19081)Beijing Municipal Administration of Hospitals Clinical Medicine Development of Special Funding Support(XML201714).
文摘Cleft lip and/or palate(CLP)are the most common craniofacial malformations in humans.Speech problems often persist even after cleft repair,such that follow-up articulation training is usually required.However,the neural mechanism behind effective articulation training remains largely unknown.We used fMRI to investigate the differences in brain activation,functional connectivity,and effective connectivity across CLP patients with and without articulation training and matched normal participants.We found that training promoted task-related brain activation among the articulation-related brain networks,as well as the global attributes and nodal efficiency in the functional-connectivity-based graph of the network.Our results reveal the neural correlates of effective articulation training in CLP patients,and this could contribute to the future improvement of the post-repair articulation training program.
