Potential high-temperature risks exist in heat-prone components of electric moped charging devices,such as sockets,interfaces,and controllers.Traditional detection methods have limitations in terms of real-time perfor...Potential high-temperature risks exist in heat-prone components of electric moped charging devices,such as sockets,interfaces,and controllers.Traditional detection methods have limitations in terms of real-time performance and monitoring scope.To address this,a temperature detection method based on infrared image processing has been proposed:utilizing the median filtering algorithm to denoise the original infrared image,then applying an image segmentation algorithm to divide the image.展开更多
Third-row transition-metal complexes remain a key component in the preparation of light-emitting layers for future OLED technology.Hence,it is of utmost importance to expand their emission peak wavelengths into the tr...Third-row transition-metal complexes remain a key component in the preparation of light-emitting layers for future OLED technology.Hence,it is of utmost importance to expand their emission peak wavelengths into the true-blue(~460–470 nm)and near-infrared(NIR)regions(~700–1000 nm).Stable true-blue phosphors are expected to excel in commercially available lighting luminaries and visual devices,such as displays and monitors,while efficient NIR emitters will enable new applications such as sensing,imaging,and optical communication.In theory,these advanced emitters can be assembled using transition metals such as iridium and platinum and judiciously designed chelates,as elaborated in this chemistry frontier article.展开更多
Organic-inorganic hybrid halide perovskites are widely used in optoelectronic devices,such as solar cells and light-emitting devices.Pursuing solutions to overcome the key problem of instability shown by most used MAP...Organic-inorganic hybrid halide perovskites are widely used in optoelectronic devices,such as solar cells and light-emitting devices.Pursuing solutions to overcome the key problem of instability shown by most used MAPbI_(3)materials,all-inorganic perovskites like CsPbI_(3)are attracting considerable attention.Unfortunately,CsPbI_(3)still suffers from significant issues relating to chemical instability and toxicity due to the presence of Pb atoms;therefore,it is necessary to carry out a profound review of the properties of all-inorganic perovskites to overcome these problems.Experimental laboratories cannot afford,in terms of money and time,to synthesize and characterize large numbers of compounds to rigorously assess the outcomes.Therefore,a systematic density functional theory study of the family of all-inorganic perovskites with the general formula CsPb1-bSnb(I1-xBrx)_(3)has been performed,covering the entire chemical composition range and elucidating the connections between composition and the structural,thermodynamic,and mechanical properties,in addition to any effects on stability.Our results allow us to gain significant insight in the search for new all-inorganic perovskites with tailored structural,thermodynamic,and mechanical properties via fine-tuning the chemical composition.展开更多
Inspired by the breakthrough of three-dimensional hybrid perovskite CH_(3)NH_(3)PbI_(3),two-dimensional(2D)layered organic-inorganic halide perovskites are emerging as another promising class of hybrid materials for o...Inspired by the breakthrough of three-dimensional hybrid perovskite CH_(3)NH_(3)PbI_(3),two-dimensional(2D)layered organic-inorganic halide perovskites are emerging as another promising class of hybrid materials for optoelectronic devices,such as photodetectors fabricated on lead halide perovskites.However,the majority of such 2D materials exhibit photosensitivity to visible light,while few candidates have been reported to exhibit visible-blind ultraviolet(UV)photoelectric response.Here,we present a new hybrid material,(1,4-butyldiammonium)CdBr_(4)(1),in which the corner-sharing CdBr_(6)octahedra construct the 2D perovskite-type inorganic frameworks.The optical bandgap(Eg)of 1 is estimated to be~3.45 eV.Particularly,1 shows spectral-selective photoconductivity,that is,it is sensitive to UV-light illumination below 360 nm but almost blind to the standard visible light(above 400 nm),disclosing the potential of 1 for visible-blind ultraviolet photodetection.Further theoretical analyses of its electronic structure and energy gap disclose that the inorganic perovskite architecture dominates the optical bandgap.It is believed that this work provides a potential route for the design and fabrication of new 2D hybrid perovskite materials with a UV photoelectric response.展开更多
Multifunctional molecular magnetic materials have promising potential for use as future molecular devices,such as for magneto-luminescence sensing,optical switching,information storage,etc.Lanthanide ions have been co...Multifunctional molecular magnetic materials have promising potential for use as future molecular devices,such as for magneto-luminescence sensing,optical switching,information storage,etc.Lanthanide ions have been considered as excellent candidates to construct molecular switches as they are very sensitive to the subtle changes of structure including the change of molecular geometry,bond distance,even crystal packing,etc,while for transition metal ions,in most cases,only the change of electronic configuration can cause a switch of magnetic properties.This review aims to summarize the effects of stimuli-induced structural transformations on the magnetic relaxation involving light-,solvato-,proton- and redox-switching of Ln-SMM behaviour.Emphasis is placed on the role played by external stimuli in reversibly modulating the magnetic properties realized in the systems with single-crystal-to-single-crystal structural transformation.展开更多
The design and preparation of highly efficient and durable electrocatalysts for the oxygen reduction reaction(ORR)and the oxygen evolution reaction(OER)is essential due to their applications in many green energy conve...The design and preparation of highly efficient and durable electrocatalysts for the oxygen reduction reaction(ORR)and the oxygen evolution reaction(OER)is essential due to their applications in many green energy conversion devices,such as fuel cells and rechargeable metal–air batteries.Herein,we report a Co/Co9S8 composite catalyst,which is coupled with reduced graphene oxide(rGO)and multi-walled carbon nanotubes(MWCNTs)via a combined hydrothermal reaction with a calcination method.Benefiting from the unique porous scaffold structures and synergistic interactions between rGO/MWCNT and Co/Co9S8,the electrocatalyst(Co/Co9S8/rGO/MWCNT-800)exhibits high electrochemical activity for the ORR,showing a four-electron oxygen reduction pathway with an onset potential of 0.946 V(vs.RHE)in alkaline medium.Meanwhile,the electrocatalyst shows high electrochemical stability,excellent selectivity and methanol tolerance over the commercial Pt/C.It also exhibits good overall oxygen electrode activity(ΔE=EOER,10−EORR,1/2 of 890 mV).The present work highlights a potential general strategy for developing carbon-based transition metal sulfide nanocomposites as cathodes with better performance in the ORR/OER.展开更多
Wearable technology has revolutionized personalized healthcare and human–machine interfaces[1,2].While conventional devices,such as watches,rings,and chest straps,demonstrate utility in localized physiological monito...Wearable technology has revolutionized personalized healthcare and human–machine interfaces[1,2].While conventional devices,such as watches,rings,and chest straps,demonstrate utility in localized physiological monitoring,they exhibit inherent limitations in mechanical compliance and ergonomic adaptability.These systems fundamentally lack the capability to capture the body’s spatially distributed,multimodal biosignals(biopotential,optical,thermal,and mechanical)with precision due to their single-node measurement paradigm.展开更多
The concept of gait synergy provides novel human-machine interfaces and has been applied to the control of lower limb assistive devices,such as powered prostheses and exoskeletons.Specifically,on the basis of gait syn...The concept of gait synergy provides novel human-machine interfaces and has been applied to the control of lower limb assistive devices,such as powered prostheses and exoskeletons.Specifically,on the basis of gait synergy,the assistive device can generate/predict the appropriate reference trajectories precisely for the affected or missing parts from the motions of sound parts of the patients.Optimal modeling for gait synergy methods that involves optimal combinations of features(inputs)is required to achieve synergic trajectories that improve human–machine interaction.However,previous studies lack thorough discussions on the optimal methods for synergy modeling.In addition,feature selection(FS)that is crucial for reducing data dimensionality and improving modeling quality has often been neglected in previous studies.Here,we comprehensively investigated modeling methods and FS using 4 up-to-date neural networks:sequence-to-sequence(Seq2Seq),long short-term memory(LSTM),recurrent neural network(RNN),and gated recurrent unit(GRU).We also conducted complete FS using 3 commonly used methods:random forest,information gain,and Pearson correlation.Our findings reveal that Seq2Seq(mean absolute error:0.404°and 0.596°,respectively)outperforms LSTM,RNN,and GRU for both interlimb and intralimb synergy modeling.Furthermore,FS is proven to significantly improve Seq2Seq’s modeling performance(P<0.05).FS-Seq2Seq even outperforms methods used in existing studies.Therefore,we propose FSSeq2Seq as a 2-stage strategy for gait synergy modeling in lower limb assistive devices with the aim of achieving synergic and user-adaptive trajectories that improve human-machine interactions.展开更多
基金supported by the National Key Research and Development Project of China(No.2023YFB3709605)the National Natural Science Foundation of China(No.62073193)the National College Student Innovation Training Program(No.202310422122)。
文摘Potential high-temperature risks exist in heat-prone components of electric moped charging devices,such as sockets,interfaces,and controllers.Traditional detection methods have limitations in terms of real-time performance and monitoring scope.To address this,a temperature detection method based on infrared image processing has been proposed:utilizing the median filtering algorithm to denoise the original infrared image,then applying an image segmentation algorithm to divide the image.
基金supported by research funds from Innovation and Technology Fund(ITS/196/20)Research Grant Council(CityU 11304221 and 11312722)City University of Hong Kong,Hong Kong SAR.
文摘Third-row transition-metal complexes remain a key component in the preparation of light-emitting layers for future OLED technology.Hence,it is of utmost importance to expand their emission peak wavelengths into the true-blue(~460–470 nm)and near-infrared(NIR)regions(~700–1000 nm).Stable true-blue phosphors are expected to excel in commercially available lighting luminaries and visual devices,such as displays and monitors,while efficient NIR emitters will enable new applications such as sensing,imaging,and optical communication.In theory,these advanced emitters can be assembled using transition metals such as iridium and platinum and judiciously designed chelates,as elaborated in this chemistry frontier article.
基金supported by the Ministerio de Ciencia e Innovación through the project BESTMAT-QC(PID2019-107137RB-C22).
文摘Organic-inorganic hybrid halide perovskites are widely used in optoelectronic devices,such as solar cells and light-emitting devices.Pursuing solutions to overcome the key problem of instability shown by most used MAPbI_(3)materials,all-inorganic perovskites like CsPbI_(3)are attracting considerable attention.Unfortunately,CsPbI_(3)still suffers from significant issues relating to chemical instability and toxicity due to the presence of Pb atoms;therefore,it is necessary to carry out a profound review of the properties of all-inorganic perovskites to overcome these problems.Experimental laboratories cannot afford,in terms of money and time,to synthesize and characterize large numbers of compounds to rigorously assess the outcomes.Therefore,a systematic density functional theory study of the family of all-inorganic perovskites with the general formula CsPb1-bSnb(I1-xBrx)_(3)has been performed,covering the entire chemical composition range and elucidating the connections between composition and the structural,thermodynamic,and mechanical properties,in addition to any effects on stability.Our results allow us to gain significant insight in the search for new all-inorganic perovskites with tailored structural,thermodynamic,and mechanical properties via fine-tuning the chemical composition.
基金supported by the NSFC(21525104,21833010,21622108,51502290,21601188)the NSF of Fujian Province(2015J05040)+1 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB20000000)the Youth Innovation Promotion of CAS(2014262 and 2015240).
文摘Inspired by the breakthrough of three-dimensional hybrid perovskite CH_(3)NH_(3)PbI_(3),two-dimensional(2D)layered organic-inorganic halide perovskites are emerging as another promising class of hybrid materials for optoelectronic devices,such as photodetectors fabricated on lead halide perovskites.However,the majority of such 2D materials exhibit photosensitivity to visible light,while few candidates have been reported to exhibit visible-blind ultraviolet(UV)photoelectric response.Here,we present a new hybrid material,(1,4-butyldiammonium)CdBr_(4)(1),in which the corner-sharing CdBr_(6)octahedra construct the 2D perovskite-type inorganic frameworks.The optical bandgap(Eg)of 1 is estimated to be~3.45 eV.Particularly,1 shows spectral-selective photoconductivity,that is,it is sensitive to UV-light illumination below 360 nm but almost blind to the standard visible light(above 400 nm),disclosing the potential of 1 for visible-blind ultraviolet photodetection.Further theoretical analyses of its electronic structure and energy gap disclose that the inorganic perovskite architecture dominates the optical bandgap.It is believed that this work provides a potential route for the design and fabrication of new 2D hybrid perovskite materials with a UV photoelectric response.
基金the National Natural Science Foundation of China(Grants 21525103 and 21871247)Key Research Program of Frontier Sciences,CAS(Grant ZDBS-LY-SLH023)for financial support.J.T.gratefully acknowledges support of the Royal Society-Newton Advanced Fellowship(NA160075)。
文摘Multifunctional molecular magnetic materials have promising potential for use as future molecular devices,such as for magneto-luminescence sensing,optical switching,information storage,etc.Lanthanide ions have been considered as excellent candidates to construct molecular switches as they are very sensitive to the subtle changes of structure including the change of molecular geometry,bond distance,even crystal packing,etc,while for transition metal ions,in most cases,only the change of electronic configuration can cause a switch of magnetic properties.This review aims to summarize the effects of stimuli-induced structural transformations on the magnetic relaxation involving light-,solvato-,proton- and redox-switching of Ln-SMM behaviour.Emphasis is placed on the role played by external stimuli in reversibly modulating the magnetic properties realized in the systems with single-crystal-to-single-crystal structural transformation.
基金support from the National Natural Science Foundation of China(No.21673098 and No.21871042)the Joint Program of Jilin Province and Jilin University(SXGJQY2017-1)the Jilin Provincial Science&Technology Department(20190303039SF).
文摘The design and preparation of highly efficient and durable electrocatalysts for the oxygen reduction reaction(ORR)and the oxygen evolution reaction(OER)is essential due to their applications in many green energy conversion devices,such as fuel cells and rechargeable metal–air batteries.Herein,we report a Co/Co9S8 composite catalyst,which is coupled with reduced graphene oxide(rGO)and multi-walled carbon nanotubes(MWCNTs)via a combined hydrothermal reaction with a calcination method.Benefiting from the unique porous scaffold structures and synergistic interactions between rGO/MWCNT and Co/Co9S8,the electrocatalyst(Co/Co9S8/rGO/MWCNT-800)exhibits high electrochemical activity for the ORR,showing a four-electron oxygen reduction pathway with an onset potential of 0.946 V(vs.RHE)in alkaline medium.Meanwhile,the electrocatalyst shows high electrochemical stability,excellent selectivity and methanol tolerance over the commercial Pt/C.It also exhibits good overall oxygen electrode activity(ΔE=EOER,10−EORR,1/2 of 890 mV).The present work highlights a potential general strategy for developing carbon-based transition metal sulfide nanocomposites as cathodes with better performance in the ORR/OER.
基金supported by the National Natural Science Foundation of China(52125201)China Postdoctoral Science Foundation(2024M751716)+1 种基金the Postdoctoral Fellowship Program of CPSF(GZB20230328)the Shuimu Tsinghua Scholar Program.
文摘Wearable technology has revolutionized personalized healthcare and human–machine interfaces[1,2].While conventional devices,such as watches,rings,and chest straps,demonstrate utility in localized physiological monitoring,they exhibit inherent limitations in mechanical compliance and ergonomic adaptability.These systems fundamentally lack the capability to capture the body’s spatially distributed,multimodal biosignals(biopotential,optical,thermal,and mechanical)with precision due to their single-node measurement paradigm.
基金supported by the National Natural Science Foundation of China(nos.32360196,and 32160204)the Key R&D Project of Hainan Province(grant nos.ZDYF2022SHFZ302 and ZDYF2022SHFZ275)+6 种基金the Major Science and Technology Projects of Hainan Province(grant no.ZDKJ2021032)Hainan Province Clinical Medical Center(no.0202067)Science,Technology,and Innovation Commission of Shenzhen Municipality(STICproject no.SGDX20220530111005036)Basic and Applied Basic Research Fund of Guangdong Province:Regional Joint Fund Project Youth Fund(project no.2021A1515110356)Shenzhen Science and Technology Plan Project(project no.JCYJ20220818101407016)by the Project of Sanya Yazhou Bay Science and Technology City(no.SCKJJYRC-2023-27).
文摘The concept of gait synergy provides novel human-machine interfaces and has been applied to the control of lower limb assistive devices,such as powered prostheses and exoskeletons.Specifically,on the basis of gait synergy,the assistive device can generate/predict the appropriate reference trajectories precisely for the affected or missing parts from the motions of sound parts of the patients.Optimal modeling for gait synergy methods that involves optimal combinations of features(inputs)is required to achieve synergic trajectories that improve human–machine interaction.However,previous studies lack thorough discussions on the optimal methods for synergy modeling.In addition,feature selection(FS)that is crucial for reducing data dimensionality and improving modeling quality has often been neglected in previous studies.Here,we comprehensively investigated modeling methods and FS using 4 up-to-date neural networks:sequence-to-sequence(Seq2Seq),long short-term memory(LSTM),recurrent neural network(RNN),and gated recurrent unit(GRU).We also conducted complete FS using 3 commonly used methods:random forest,information gain,and Pearson correlation.Our findings reveal that Seq2Seq(mean absolute error:0.404°and 0.596°,respectively)outperforms LSTM,RNN,and GRU for both interlimb and intralimb synergy modeling.Furthermore,FS is proven to significantly improve Seq2Seq’s modeling performance(P<0.05).FS-Seq2Seq even outperforms methods used in existing studies.Therefore,we propose FSSeq2Seq as a 2-stage strategy for gait synergy modeling in lower limb assistive devices with the aim of achieving synergic and user-adaptive trajectories that improve human-machine interactions.
