Learning progressions divide the logical system of a subject into ordered and continuously developing levels that are suitable for the cognitive development level of students,which plays an important role in understan...Learning progressions divide the logical system of a subject into ordered and continuously developing levels that are suitable for the cognitive development level of students,which plays an important role in understanding students’learning process.This paper focuses on the theme of“kinetic energy”in high school physics as the research object.Firstly,the concept map was used to represent the relationship between knowledge,and then five core concepts were selected based on the opinions of high school teachers.Secondly,the test tools were compiled and tested based on the relevant test questions.Finally,the paper analyzed the results based on the Rasch model,clarified students’cognitive development level of“kinetic energy”and constructed the learning progressions of“kinetic energy”based on the logical order of subject knowledge.The research provides theoretical and methodological support for the study of other subjects and learning progressions,and provides a valuable reference for high school teachers to effectively carry out the instruction of“kinetic energy.”展开更多
Ruthenium(Ru)-based materials are considered significantly promising alternatives to supersede platinum(Pt)-based catalysts toward the hydrogen evolution reaction(HER),especially under alkaline conditions.Herein,we ad...Ruthenium(Ru)-based materials are considered significantly promising alternatives to supersede platinum(Pt)-based catalysts toward the hydrogen evolution reaction(HER),especially under alkaline conditions.Herein,we adopt a gradual substitute method to rationally design phosphorus and nitrogen co-doped carbon matrix-supported Ru nanoparticles with an anomalous dominated(100)index facet(Ru(100)/NPC)for the efficient alkaline hydrogen evolution reaction(HER).Experimental and theoretical analyses confirmed that the water dissociation process is drastically boosted by the strong water adsorption at Ru sites with eight-fold coordination in Ru(100),while the efficient hydrogen generation process is achieved through hydrogen spillover to transfer hydrogen from the Ru sites with eight-fold coordination to Ru sites with ten-fold coordination in Ru(100)that demonstrated remarkable hydrogen formation activity.Consequently,the obtained Ru(100)/NPC exhibits an ultralow overpotential(16 mV)at 10 mA cm^(-2),much better than the commercial benchmark Pt/C.This work provides a new opportunity for the development of an ideal electrocatalyst for HER in alkaline media.展开更多
基金Jilin Province Education Science“14th Five Year Plan”2021 Annual Project“Research on Middle School Physics Teaching Based on STEM Education Concept”(GH21032).
文摘Learning progressions divide the logical system of a subject into ordered and continuously developing levels that are suitable for the cognitive development level of students,which plays an important role in understanding students’learning process.This paper focuses on the theme of“kinetic energy”in high school physics as the research object.Firstly,the concept map was used to represent the relationship between knowledge,and then five core concepts were selected based on the opinions of high school teachers.Secondly,the test tools were compiled and tested based on the relevant test questions.Finally,the paper analyzed the results based on the Rasch model,clarified students’cognitive development level of“kinetic energy”and constructed the learning progressions of“kinetic energy”based on the logical order of subject knowledge.The research provides theoretical and methodological support for the study of other subjects and learning progressions,and provides a valuable reference for high school teachers to effectively carry out the instruction of“kinetic energy.”
基金the Taishan Scholar Program of Shandong Province,China(ts201712045)the Natural Science Foundation of Shandong Province of China(ZR2022QB100,ZR2022QB163).
文摘Ruthenium(Ru)-based materials are considered significantly promising alternatives to supersede platinum(Pt)-based catalysts toward the hydrogen evolution reaction(HER),especially under alkaline conditions.Herein,we adopt a gradual substitute method to rationally design phosphorus and nitrogen co-doped carbon matrix-supported Ru nanoparticles with an anomalous dominated(100)index facet(Ru(100)/NPC)for the efficient alkaline hydrogen evolution reaction(HER).Experimental and theoretical analyses confirmed that the water dissociation process is drastically boosted by the strong water adsorption at Ru sites with eight-fold coordination in Ru(100),while the efficient hydrogen generation process is achieved through hydrogen spillover to transfer hydrogen from the Ru sites with eight-fold coordination to Ru sites with ten-fold coordination in Ru(100)that demonstrated remarkable hydrogen formation activity.Consequently,the obtained Ru(100)/NPC exhibits an ultralow overpotential(16 mV)at 10 mA cm^(-2),much better than the commercial benchmark Pt/C.This work provides a new opportunity for the development of an ideal electrocatalyst for HER in alkaline media.
