The application of ionic liquids in perovskite has attracted wide-spread attention for its astounding performance improvement of perovskite solar cells(PSCs).However,the detailed mechanisms behind the improvement rema...The application of ionic liquids in perovskite has attracted wide-spread attention for its astounding performance improvement of perovskite solar cells(PSCs).However,the detailed mechanisms behind the improvement remain mysterious.Herein,a series of imidazolium-based ionic liquids(IILs)with different cations and anions is systematically investigated to elucidate the passivation mechanism of IILs on inorganic perovskites.It is found that IILs display the following advantages:(1)They form ionic bonds with Cs^(+)and Pb^(2+)cations on the surface and at the grain boundaries of perovskite films,which could effectively heal/reduce the Cs^(+)/I−vacancies and Pb-related defects;(2)They serve as a bridge between the perovskite and the hole-transport-layer for effective charge extraction and transfer;and(3)They increase the hydrophobicity of the perovskite surface to further improve the stability of the CsPbI_(2)Br PSCs.The combination of the above effects results in suppressed non-radiative recombination loss in CsPbI_(2)Br PSCs and an impressive power conversion efficiency of 17.02%.Additionally,the CsPbI_(2)Br PSCs with IILs surface modification exhibited improved ambient and light illumination stability.Our results provide guidance for an indepth understanding of the passivation mechanism of IILs in inorganic perovskites.展开更多
It is widely believed that the matter created in p-p collisions exhibits a similar collective behavior as that formed in heavy ion collisions. In this paper, by taking into account the effects of thermal motion, the t...It is widely believed that the matter created in p-p collisions exhibits a similar collective behavior as that formed in heavy ion collisions. In this paper, by taking into account the effects of thermal motion, the transverse momentum distributions of identified charged particles are discussed in the scope of the hydrodynamic model including phase transition. The theoretical model gives a good description to the data collected in p-p collisions at LHC energies for the transverse momentum up to about .展开更多
The lower-limb robotic prostheses can provide assistance for amputees’daily activities by restoring the biomechanical functions of missing limb(s).To set proper control strategies and develop the corresponding contro...The lower-limb robotic prostheses can provide assistance for amputees’daily activities by restoring the biomechanical functions of missing limb(s).To set proper control strategies and develop the corresponding controller for robotic prosthesis,a prosthesis user’s intent must be acquired in time,which is still a major challenge and has attracted intensive attentions.This work focuses on the robotic prosthesis user’s locomotion intent recognition based on the noninvasive sensing methods from the recognition task perspective(locomotion mode recognition,gait event detection,and continuous gait phase estimation)and reviews the state-ofthe-art intent recognition techniques in a lower-limb prosthesis scope.The current research status,including recognition approach,progress,challenges,and future prospects in the human’s intent recognition,has been reviewed.In particular for the recognition approach,the paper analyzes the recent studies and discusses the role of each element in locomotion intent recognition.This work summarizes the existing research results and problems and contributes a general framework for the intent recognition based on lower-limb prosthesis.展开更多
Hydroformylation is an atom-economic and highly efficient transformation from readily available olefins to various synthetically important carbonyl compounds[1].By using this transformation,the largest amount of fine ...Hydroformylation is an atom-economic and highly efficient transformation from readily available olefins to various synthetically important carbonyl compounds[1].By using this transformation,the largest amount of fine chemicals have been produced in the global chemical industry every year.展开更多
基金support from the National Natural Science Foundation of China(62074095)the National Key Research and Development Program of China(2016YFA0202403)+3 种基金the Fundamental Research Funds for the Central Universities(GK202002001)the 111 Project(Grant No.B21005)the DNL Cooperation Fund CAS(DNL180311)the support of H2 cluster in Xi’an Jiaotong University.
文摘The application of ionic liquids in perovskite has attracted wide-spread attention for its astounding performance improvement of perovskite solar cells(PSCs).However,the detailed mechanisms behind the improvement remain mysterious.Herein,a series of imidazolium-based ionic liquids(IILs)with different cations and anions is systematically investigated to elucidate the passivation mechanism of IILs on inorganic perovskites.It is found that IILs display the following advantages:(1)They form ionic bonds with Cs^(+)and Pb^(2+)cations on the surface and at the grain boundaries of perovskite films,which could effectively heal/reduce the Cs^(+)/I−vacancies and Pb-related defects;(2)They serve as a bridge between the perovskite and the hole-transport-layer for effective charge extraction and transfer;and(3)They increase the hydrophobicity of the perovskite surface to further improve the stability of the CsPbI_(2)Br PSCs.The combination of the above effects results in suppressed non-radiative recombination loss in CsPbI_(2)Br PSCs and an impressive power conversion efficiency of 17.02%.Additionally,the CsPbI_(2)Br PSCs with IILs surface modification exhibited improved ambient and light illumination stability.Our results provide guidance for an indepth understanding of the passivation mechanism of IILs in inorganic perovskites.
文摘It is widely believed that the matter created in p-p collisions exhibits a similar collective behavior as that formed in heavy ion collisions. In this paper, by taking into account the effects of thermal motion, the transverse momentum distributions of identified charged particles are discussed in the scope of the hydrodynamic model including phase transition. The theoretical model gives a good description to the data collected in p-p collisions at LHC energies for the transverse momentum up to about .
基金supported by the National Key R&D Program of China(Nos.2018YFB1307302,2018YFF0300606),the National Natural Science Foundation of China(No.91648207)the Beijing Natural Science Foundation(No.L182001)the Beijing Municipal Science and Technology Project(No.Z181100009218007).
文摘The lower-limb robotic prostheses can provide assistance for amputees’daily activities by restoring the biomechanical functions of missing limb(s).To set proper control strategies and develop the corresponding controller for robotic prosthesis,a prosthesis user’s intent must be acquired in time,which is still a major challenge and has attracted intensive attentions.This work focuses on the robotic prosthesis user’s locomotion intent recognition based on the noninvasive sensing methods from the recognition task perspective(locomotion mode recognition,gait event detection,and continuous gait phase estimation)and reviews the state-ofthe-art intent recognition techniques in a lower-limb prosthesis scope.The current research status,including recognition approach,progress,challenges,and future prospects in the human’s intent recognition,has been reviewed.In particular for the recognition approach,the paper analyzes the recent studies and discusses the role of each element in locomotion intent recognition.This work summarizes the existing research results and problems and contributes a general framework for the intent recognition based on lower-limb prosthesis.
文摘Hydroformylation is an atom-economic and highly efficient transformation from readily available olefins to various synthetically important carbonyl compounds[1].By using this transformation,the largest amount of fine chemicals have been produced in the global chemical industry every year.
