Lithium-sulfur(Li-S)batteries with the merits of high theoretical capacity and high energy density have gained significant attention as the next-generation energy storage devices.Unfortunately,the main pressing issues...Lithium-sulfur(Li-S)batteries with the merits of high theoretical capacity and high energy density have gained significant attention as the next-generation energy storage devices.Unfortunately,the main pressing issues of sluggish reaction kinetics and severe shuttling of polysulfides hampered their practical application.To overcome these obstacles,various strategies adopting high-efficient electrocatalysts have been explored to enable the rapid polysulfide conversions and thereby suppressing the polysulfide shuttling.This review first summarizes the recent progress on electrocatalysts involved in hosts,interlayers,and protective layers.Then,these electrocatalysts in Li-S batteries are analyzed by listing representative works,from the viewpoints of design concepts,engineering strategies,working principles,and electrochemical performance.Finally,the remaining issues/challenges and future perspectives facing electrocatalysts are given and discussed.This review may provide new guidance for the future construction of electrocatalysts and their further utilizations in high-performance Li-S batteries.展开更多
In this paper,a class of slow reaction-diffusion equations with nonlocal source and inner absorption terms are studied.By using the technique of improved differential inequality,the lower bounds of blow up time for th...In this paper,a class of slow reaction-diffusion equations with nonlocal source and inner absorption terms are studied.By using the technique of improved differential inequality,the lower bounds of blow up time for the system under either homogeneous Dirichlet or nonhomogeneous Neumann boundary conditions are obtained.展开更多
Halide exchange offers a versatile way to modify the properties of halide perovskites,but it is particularly challenging to slow the reaction rate to restrain defect growth in the products.Herein,we propose a slow hal...Halide exchange offers a versatile way to modify the properties of halide perovskites,but it is particularly challenging to slow the reaction rate to restrain defect growth in the products.Herein,we propose a slow halide exchange strategy to simultaneously fine-tune the optical and microstructural characteristics of CsPbIBr_(2) films by physically pairing CsPbIBr_(2) and CH_(3)NH_(3)PbI_(3) films.Once a proper heating treatment is applied,halide exchange of Br^(-)and I^(-)ions between the films is activated,and the reaction rate can be well-controlled by the heating recipe,in which a high temperature can accelerate the exchange reaction,while a low temperature slows or stops it.By using an optimal halide exchange temperature(110℃)and time(2 h),the parent CsPbIBr_(2) film was transformed into high-quality CsPbI_(1+x)Br_(2-x) film,featuring an extended absorption onset from 590 to 625 nm,coarsened grains,improved crystallinity,reduced surface roughness,suppressed halide phase segregation,and identical stability to the pristine film.Accordingly,the efficiency of a carbon-based,all-inorganic perovskite solar cell(PSC)was boosted to 10.94%,which was much higher than that of the pristine CsPbIBr_(2) film(8.21%).The CsPbI_(1+x)Br_(2-x) PSC also possessed excellent tolerance against heat and moisture stresses.展开更多
Objective: To investigate the electrophysiology effects and mechanism of iron overload on the slow response autorhythmic cells in the left ventricular outflow tract of guinea pigs.Methods: Standard microelectrode cell...Objective: To investigate the electrophysiology effects and mechanism of iron overload on the slow response autorhythmic cells in the left ventricular outflow tract of guinea pigs.Methods: Standard microelectrode cell recording techniques were adopted to observe the electrophysiological effects of different concentrations of Fe^(2+)(100 μmol/L, 200 μmol/L) on the left ventricular outflow tract autorhythmic cells.Heart tissues were perfused with FeSO_4(200 μmol/L) combing with CaCl_2(4.2 mmol/L), Verapamil,(1 μmol/L), and nickel chloride(200μmol/L) respectively to observe the influences of these contents on electrophysiology of FeSO_4(200μmol/L) on the left ventricular outflow tract autorhythmic cells.Results: Fe^(2+)at both 100 μmol/L and 200 μmol/L could change the electrophysiological parameters of the slow response autorhythmic cells of the left ventricular outflow tract in a concentrationdependent manner resulting into decrease in Vmax, APA and MDP, slower RPF and VDD, and prolonged APD_(50) and APD_(90)(P all <0.05).Besides, perfusion of increased Ca^(2+) concentration could partially offset the electrophysiological effects of Fe^(2+)(200 μmol/L).The L-type calcium channel(LTCC) blocker Verapamil(1 μmol/L) could block the electrophysiological effects of Fe^(2+)(200 μmol/L).But the T-type calcium channel(TTCC) blocker nickel chloride(NiCl_2, 200 μmol/L) could not block the electrophysiological effects of Fe^(2+)(200 μmol/L).Conclusions: Fe^(2+) can directly change the electrophysiological characteristics of the slow response autorhythmic cells of the left ventricular outflow tract probably through the L-type calcium channel.展开更多
基金supported by the Yong Scientific Foundation of Anhui University of Technology for Top Talent(No.DT2100000947)Natural Science Foundation of Anhui Province Education Commission(No.KJ2020A0269)+1 种基金the Scientific Research Foundation of Anhui University of Technology for Talent Introduction(No.DT19100069)the Yong Scientific Research Foundation of Anhui University of Technology(No.QZ202003).
文摘Lithium-sulfur(Li-S)batteries with the merits of high theoretical capacity and high energy density have gained significant attention as the next-generation energy storage devices.Unfortunately,the main pressing issues of sluggish reaction kinetics and severe shuttling of polysulfides hampered their practical application.To overcome these obstacles,various strategies adopting high-efficient electrocatalysts have been explored to enable the rapid polysulfide conversions and thereby suppressing the polysulfide shuttling.This review first summarizes the recent progress on electrocatalysts involved in hosts,interlayers,and protective layers.Then,these electrocatalysts in Li-S batteries are analyzed by listing representative works,from the viewpoints of design concepts,engineering strategies,working principles,and electrochemical performance.Finally,the remaining issues/challenges and future perspectives facing electrocatalysts are given and discussed.This review may provide new guidance for the future construction of electrocatalysts and their further utilizations in high-performance Li-S batteries.
基金Supported by the Natural Science Foundation of Shaanxi Province(2019JM-534)the Youth Innovation Team of Shaanxi Universities+7 种基金the 14th Five Year Plan for Educational Science in Shaanxi Province(SGH21Y0308)Key Topic of China Higher Education Association(21DFD04)Higher Education Teaching Reform Project of Xi’an International University(2023B03)2022 Annual Planning Project of China Association of Private Education(School Development)(CANFZG22222)Project of Department of Education of Shaanxi Provincethe 2022 Annual Topic of the"14th Five-Year Plan"of Shaanxi Provincial Educational Science(SGH22Y1885)Project of Qi Fang Education Research Institute of Xi’an International University(23mjy10)Special Project of the Shaanxi Provincial Social Science Found in 2023(2023SJ12,2023LS04)。
文摘In this paper,a class of slow reaction-diffusion equations with nonlocal source and inner absorption terms are studied.By using the technique of improved differential inequality,the lower bounds of blow up time for the system under either homogeneous Dirichlet or nonhomogeneous Neumann boundary conditions are obtained.
基金financially supported by the National Natural Science Foundation of China (61804113, 61874083 and 61704128)the Innovative Postdocs Supporting Program (BX20190261)+1 种基金the China Postdoctoral Science Foundation (2019M663628)the Natural Science Foundation of Shaanxi Province (2018ZDCXL-GY-0802-02 and 2017JM6049)
文摘Halide exchange offers a versatile way to modify the properties of halide perovskites,but it is particularly challenging to slow the reaction rate to restrain defect growth in the products.Herein,we propose a slow halide exchange strategy to simultaneously fine-tune the optical and microstructural characteristics of CsPbIBr_(2) films by physically pairing CsPbIBr_(2) and CH_(3)NH_(3)PbI_(3) films.Once a proper heating treatment is applied,halide exchange of Br^(-)and I^(-)ions between the films is activated,and the reaction rate can be well-controlled by the heating recipe,in which a high temperature can accelerate the exchange reaction,while a low temperature slows or stops it.By using an optimal halide exchange temperature(110℃)and time(2 h),the parent CsPbIBr_(2) film was transformed into high-quality CsPbI_(1+x)Br_(2-x) film,featuring an extended absorption onset from 590 to 625 nm,coarsened grains,improved crystallinity,reduced surface roughness,suppressed halide phase segregation,and identical stability to the pristine film.Accordingly,the efficiency of a carbon-based,all-inorganic perovskite solar cell(PSC)was boosted to 10.94%,which was much higher than that of the pristine CsPbIBr_(2) film(8.21%).The CsPbI_(1+x)Br_(2-x) PSC also possessed excellent tolerance against heat and moisture stresses.
基金supported by Zhangjiakou Project of Science and Technology Studies and Development Planning(Grand No.1321078D)
文摘Objective: To investigate the electrophysiology effects and mechanism of iron overload on the slow response autorhythmic cells in the left ventricular outflow tract of guinea pigs.Methods: Standard microelectrode cell recording techniques were adopted to observe the electrophysiological effects of different concentrations of Fe^(2+)(100 μmol/L, 200 μmol/L) on the left ventricular outflow tract autorhythmic cells.Heart tissues were perfused with FeSO_4(200 μmol/L) combing with CaCl_2(4.2 mmol/L), Verapamil,(1 μmol/L), and nickel chloride(200μmol/L) respectively to observe the influences of these contents on electrophysiology of FeSO_4(200μmol/L) on the left ventricular outflow tract autorhythmic cells.Results: Fe^(2+)at both 100 μmol/L and 200 μmol/L could change the electrophysiological parameters of the slow response autorhythmic cells of the left ventricular outflow tract in a concentrationdependent manner resulting into decrease in Vmax, APA and MDP, slower RPF and VDD, and prolonged APD_(50) and APD_(90)(P all <0.05).Besides, perfusion of increased Ca^(2+) concentration could partially offset the electrophysiological effects of Fe^(2+)(200 μmol/L).The L-type calcium channel(LTCC) blocker Verapamil(1 μmol/L) could block the electrophysiological effects of Fe^(2+)(200 μmol/L).But the T-type calcium channel(TTCC) blocker nickel chloride(NiCl_2, 200 μmol/L) could not block the electrophysiological effects of Fe^(2+)(200 μmol/L).Conclusions: Fe^(2+) can directly change the electrophysiological characteristics of the slow response autorhythmic cells of the left ventricular outflow tract probably through the L-type calcium channel.
