In this work,we developed plasmonic photocatalyst composed of Cu Pd alloy nanoparticles supported on Ti N,the optimized Cu_(3)Pd_(2)/Ti N catalyst shows excellent conversion(>96%)and selectivity(>99%)for Heck re...In this work,we developed plasmonic photocatalyst composed of Cu Pd alloy nanoparticles supported on Ti N,the optimized Cu_(3)Pd_(2)/Ti N catalyst shows excellent conversion(>96%)and selectivity(>99%)for Heck reaction at 50℃ under visible light irradiation.By in-situ spectroscopic investigations,we find that visible light excitation could achieve stable metallic Cu species on the surface of Cu Pd alloy nanoparticles,thereby eliminating the inevitable surface oxides of Cu based catalyst.The in-situ formed metallic Cu species under irradiation take advantage of the strong interactions of Cu with visible light,and manifest in the localized surface plasmon resonances(LSPR)photoexcitation.Visible light excitation could further promote the charge transfer between catalytic Pd component and the support Ti N,resulting in electron-rich Pd sites on Cu Pd/Ti N.Moreover,light excitation on Cu Pd/Ti N generates strong chemisorption of iodobenzene and styrene,favoring the activation of reactants for Heck reaction.DFT calculations suggest that electron-rich Cu Pd sites ideally lower the activation energy barrier for the coupling reaction.This work provides valuable insights for mechanistic understanding of plasmonic photocatalysis.展开更多
Dielectric capacitors,serving as the indispensable components in advanced high-power energy storage devices,have attracted ever-increasing attention with the rapid development of science and technology.Among various d...Dielectric capacitors,serving as the indispensable components in advanced high-power energy storage devices,have attracted ever-increasing attention with the rapid development of science and technology.Among various dielectric capacitors,ceramic capacitors with perovskite structures show unique advantages in actual application,e.g.,excellent adaptability in high-temperature environments.And the optimization of their energy storage performance has become a hot research topic recently.This review presents the basic principles of energy storage in dielectric ceramics and introduces multi-scale synergic optimization strategies according to the key factors for superior energy storage performance.By summarizing the common points in numerous works,several universal modification strategies are reviewed,and future research on fatigue fracture of ceramic capacitors under multi-field including but not limited to force,electric,and thermal coupling conditions is also anticipated.展开更多
In order to improve soil fertility and fertilizer utilization,a subsoiling variable rate fertilization machine based on conservation tillage and precision agriculture was designed and tested.The relationship between s...In order to improve soil fertility and fertilizer utilization,a subsoiling variable rate fertilization machine based on conservation tillage and precision agriculture was designed and tested.The relationship between suspension parameters and penetrating distance was analyzed,and a matching model between fertilizing quantity and penetrating distance was established.The variable rate fertilization control machine was developed based on an Advantech PCM-9363 industrial control mainboard.The machine operates under two patterns:DGPS-based positioning and straight-line path positioning based on a planar coordinate system.This machine can perform on-demand fertilization according to the spatial differences in soil nutrients and the prescription maps pre-set before the operation.Field experiments showed the machine has a subsoiling stability of 92.5%,a soil breaking rate of 61.1%,a maximum positioning relative error of 2.68%and a maximum variable rate fertilization error of 3.89%.The subsoiling performance and variable rate fertilization indices of this machine satisfy the requirements of GB/T24675.2-2009.The tested indices meet the national and industrial standards and satisfy the design requirements.The findings of the research can be used as the structural design of the subsoiling variable rate fertilization machine.展开更多
基金supported by Shanghai Pujiang Program(No.21PJ1400400)the Research Start-up Fund at Donghua University+2 种基金the Foundation of State Key Laboratory of Coal Combustion(No.FSKLCCA2309)the National Natural Science Foundation of China(No.22302109)the Australian Research Council(No.DP230102740)。
文摘In this work,we developed plasmonic photocatalyst composed of Cu Pd alloy nanoparticles supported on Ti N,the optimized Cu_(3)Pd_(2)/Ti N catalyst shows excellent conversion(>96%)and selectivity(>99%)for Heck reaction at 50℃ under visible light irradiation.By in-situ spectroscopic investigations,we find that visible light excitation could achieve stable metallic Cu species on the surface of Cu Pd alloy nanoparticles,thereby eliminating the inevitable surface oxides of Cu based catalyst.The in-situ formed metallic Cu species under irradiation take advantage of the strong interactions of Cu with visible light,and manifest in the localized surface plasmon resonances(LSPR)photoexcitation.Visible light excitation could further promote the charge transfer between catalytic Pd component and the support Ti N,resulting in electron-rich Pd sites on Cu Pd/Ti N.Moreover,light excitation on Cu Pd/Ti N generates strong chemisorption of iodobenzene and styrene,favoring the activation of reactants for Heck reaction.DFT calculations suggest that electron-rich Cu Pd sites ideally lower the activation energy barrier for the coupling reaction.This work provides valuable insights for mechanistic understanding of plasmonic photocatalysis.
基金supported by the National Natural Science Foundation of China(52073144 and 12004181)the Natural Science Foundation of Jiangsu Province(BK20201301 and BK20200473)+2 种基金State Key Laboratory of New Ceramics and Fine Processing,Tsinghua University(KF202114)the Research Fund of State Key Laboratory of Mechanics and Control of Mechanical Structures,Nanjing University of Aeronautics and Astronautics(MCMS-I-0522G02)a Project Funded by a project of the Priority Academic Program Development(PAPD)of Jiangsu Higher Education Institutions.
文摘Dielectric capacitors,serving as the indispensable components in advanced high-power energy storage devices,have attracted ever-increasing attention with the rapid development of science and technology.Among various dielectric capacitors,ceramic capacitors with perovskite structures show unique advantages in actual application,e.g.,excellent adaptability in high-temperature environments.And the optimization of their energy storage performance has become a hot research topic recently.This review presents the basic principles of energy storage in dielectric ceramics and introduces multi-scale synergic optimization strategies according to the key factors for superior energy storage performance.By summarizing the common points in numerous works,several universal modification strategies are reviewed,and future research on fatigue fracture of ceramic capacitors under multi-field including but not limited to force,electric,and thermal coupling conditions is also anticipated.
基金The authors acknowledge that this work was financially supported by the National Natural Science Foundation of China(No.31401284)the National Key Technology Research and Development Program of the Ministry of Science and Technology of China(No.2014BAD06B03).
文摘In order to improve soil fertility and fertilizer utilization,a subsoiling variable rate fertilization machine based on conservation tillage and precision agriculture was designed and tested.The relationship between suspension parameters and penetrating distance was analyzed,and a matching model between fertilizing quantity and penetrating distance was established.The variable rate fertilization control machine was developed based on an Advantech PCM-9363 industrial control mainboard.The machine operates under two patterns:DGPS-based positioning and straight-line path positioning based on a planar coordinate system.This machine can perform on-demand fertilization according to the spatial differences in soil nutrients and the prescription maps pre-set before the operation.Field experiments showed the machine has a subsoiling stability of 92.5%,a soil breaking rate of 61.1%,a maximum positioning relative error of 2.68%and a maximum variable rate fertilization error of 3.89%.The subsoiling performance and variable rate fertilization indices of this machine satisfy the requirements of GB/T24675.2-2009.The tested indices meet the national and industrial standards and satisfy the design requirements.The findings of the research can be used as the structural design of the subsoiling variable rate fertilization machine.
