对青少年足球运动员使用课次主观疲劳度(Session-rating of perceived exertion,sRPE)的现状进行梳理,确定sRPE在青少年足球运动队中的适用范围,帮助青少年足球队进行便捷的科学化训练。方法:在PubMed、Web of Science、EBSCO、中国知...对青少年足球运动员使用课次主观疲劳度(Session-rating of perceived exertion,sRPE)的现状进行梳理,确定sRPE在青少年足球运动队中的适用范围,帮助青少年足球队进行便捷的科学化训练。方法:在PubMed、Web of Science、EBSCO、中国知网、万方等数据库以football、sRPE、youth等关键词检索文献,对纳入的队列研究、随机对照试验进行质量评价。结果:纳入41篇文献42项研究,随机对照研究3项,质量评价平均16分;队列研究39项,质量评价平均6.87分。目前针对青少年足球运动员使用sRPE的研究方向包括:检验sRPE的有效性;通过sRPE监控训练或比赛负荷;分析sRPE在恢复中的应用;比较sRPE与运动表现的关系;构建sRPE与伤病模型关联,确定二者潜在发生关系。结论:sRPE是一种简单、个性化的评估青少年训练内负荷的方式,可在训练后10~30 min通过Borg主观疲劳感知评估10或100量表(The Borg RPE Category Ratio CR-10/CR-100 Scale,Borg CR10/CR100)使用。对于青少年足球运动员,sRPE可用于:(1)监控训练内负荷,为教练员合理制定训练计划,为防止过度训练或伤病发生提供依据;(2)评估青少年足球运动员的疲劳和恢复状况;(3)青少年足球运动员有氧表现提升的训练计划制订;(4)sRPE无法准确对青少年足球运动员伤病进行预测。展开更多
Introduction Non-evaporable getter is now widely employed in many accelerators to mitigate the resistive-wall effect of the Ti-Zr-V getter coated vacuum chambers in the next generation accelerators.Methods and discuss...Introduction Non-evaporable getter is now widely employed in many accelerators to mitigate the resistive-wall effect of the Ti-Zr-V getter coated vacuum chambers in the next generation accelerators.Methods and discussions Quaternary Ti-Zr-V-Cu getter films were deposited by direct current(DC)magnetron sputtering.The DC/high frequency impedance and activation kinetics were investigated by four-probes/waveguide methods and in situ synchrotron radiation photoelectron spectroscopy(SRPES).Conclusions Compared to Ti-Zr-V films,Ti-Zr-V-Cu films showed better conductivity,which is beneficial to eliminate the resistive-wall effect.However,its initial activation temperature is above 200℃,and it needs to be activated at a higher temperature to achieve the required pumping performance.展开更多
监测运动负荷是运动训练、竞赛及康复训练的关键环节,是影响运动成绩和降低运动伤害的关键因素,也是训练规划的核心。训练负荷的监测通常是为了量化两个关联的联系:训练负荷—成绩关系(TL-P)和训练负荷—伤害关系(TL-I)。在对文献的系...监测运动负荷是运动训练、竞赛及康复训练的关键环节,是影响运动成绩和降低运动伤害的关键因素,也是训练规划的核心。训练负荷的监测通常是为了量化两个关联的联系:训练负荷—成绩关系(TL-P)和训练负荷—伤害关系(TL-I)。在对文献的系统回顾中,TL的主观测量,特别是session-RPE训练负荷量化方法(以下简称“sRPE”)的评分,被推荐为TL的主要测量方法。主观测量也可能比客观测量更敏感和一致,而且sRPE已被称为大多数运动中最常评估的TL变量。本研究运用文献资料、逻辑分析、对比分析等方法对知网、维普、web of science等国内外体育科学研究相关领域的数据库,通过综述sRPE训练负荷量化方法的概念和发展及应用于主观训练负荷监测的有效度、可靠性和局限性研究,总结该方法在当前体育科学研究中的相关研究成果和实践操作经验。展开更多
Broadly,the oxygen evolution reaction(OER)has been deeply understood as a significant part of energy conversion and storage.Nevertheless,the anions in the OER catalysts have been neglected for various reasons such as ...Broadly,the oxygen evolution reaction(OER)has been deeply understood as a significant part of energy conversion and storage.Nevertheless,the anions in the OER catalysts have been neglected for various reasons such as inactive sites,dissolution,and oxidation,amongst others.Herein,we applied a model catalyst s-Ni(OH)2 to track the anionic behavior in the catalyst during the electrochemical process to fill this gap.The advanced operando synchrotron radiation Fourier transform infrared(SR-FTIR)spectroscopy,synchrotron radiation photoelectron spectroscopy(SRPES)depth detection and differential X-ray absorption fine structure(D-XAFS)spectrum jointly point out that some oxidized sulfur species(SO_(4)^(2-))will selfoptimize new Ni–S bonds during OER process.Such amazing anionic self-optimization(ASO)behavior has never been observed in the OER process.Subsequently,the optimization-derived component shows a significantly improved electrocatalytic performance(activity,stability,etc.)compared to reference catalyst Ni(OH)_(2).Theoretical calculation further suggests that the ASO process indeed derives a thermodynamically stable structure of the OER catalyst,and then gives its superb catalytic performance by optimizing the thermodynamic and kinetic processes in the OER,respectively.This work demonstrates the vital role of anions in the electrochemical process,which will open up new perspectives for understanding OER and provide some new ideas in related fields(especially catalysis and chemistry).展开更多
The interaction of Co with ceria thin films and its influence on the sintering behavior of Au were investigated by scanning tunneling microscopy（STM）, synchrotron radiation photoemission spectroscopy（SRPES） and X-...The interaction of Co with ceria thin films and its influence on the sintering behavior of Au were investigated by scanning tunneling microscopy（STM）, synchrotron radiation photoemission spectroscopy（SRPES） and X-ray photoelectron spectroscopy（XPS）. The strong interaction between Co and CeO_2（111） leads to oxidation of Co to Co^（2＋） at 300 K, accompanied by partial reduction of ceria surface at low Co coverages. Subsequent Co deposition results in an increasing fraction of metallic Co. Annealing to high temperatures induces Co^（2＋）ions diffuse into the CeO_2 film, while the small metallic Co islands agglomerate into larger ones. The bimetallic Co–Au particles were prepared by deposition of Au on the existing Co particles on ceria surfaces. The sintering behavior of Co–Au bimetallic surfaces is found to be highly determined by the stoichiometry of ceria supports. The addition of Co to the Au/CeO_2 surface suppresses the sintering of Au particles at high temperatures in comparison with that of pure Au particles. However, Au particles are less stable on the Co/CeO_（1.82） layer than on CeO_（1.82） surface.展开更多
文摘对青少年足球运动员使用课次主观疲劳度(Session-rating of perceived exertion,sRPE)的现状进行梳理,确定sRPE在青少年足球运动队中的适用范围,帮助青少年足球队进行便捷的科学化训练。方法:在PubMed、Web of Science、EBSCO、中国知网、万方等数据库以football、sRPE、youth等关键词检索文献,对纳入的队列研究、随机对照试验进行质量评价。结果:纳入41篇文献42项研究,随机对照研究3项,质量评价平均16分;队列研究39项,质量评价平均6.87分。目前针对青少年足球运动员使用sRPE的研究方向包括:检验sRPE的有效性;通过sRPE监控训练或比赛负荷;分析sRPE在恢复中的应用;比较sRPE与运动表现的关系;构建sRPE与伤病模型关联,确定二者潜在发生关系。结论:sRPE是一种简单、个性化的评估青少年训练内负荷的方式,可在训练后10~30 min通过Borg主观疲劳感知评估10或100量表(The Borg RPE Category Ratio CR-10/CR-100 Scale,Borg CR10/CR100)使用。对于青少年足球运动员,sRPE可用于:(1)监控训练内负荷,为教练员合理制定训练计划,为防止过度训练或伤病发生提供依据;(2)评估青少年足球运动员的疲劳和恢复状况;(3)青少年足球运动员有氧表现提升的训练计划制订;(4)sRPE无法准确对青少年足球运动员伤病进行预测。
基金supported by High Energy Photon Source(HEPS),a major national science and technology infrastructure,and Xie Jialin Research Fund(No.E2546HU210)National Development and Reform Commission(2017)No.2173。
文摘Introduction Non-evaporable getter is now widely employed in many accelerators to mitigate the resistive-wall effect of the Ti-Zr-V getter coated vacuum chambers in the next generation accelerators.Methods and discussions Quaternary Ti-Zr-V-Cu getter films were deposited by direct current(DC)magnetron sputtering.The DC/high frequency impedance and activation kinetics were investigated by four-probes/waveguide methods and in situ synchrotron radiation photoelectron spectroscopy(SRPES).Conclusions Compared to Ti-Zr-V films,Ti-Zr-V-Cu films showed better conductivity,which is beneficial to eliminate the resistive-wall effect.However,its initial activation temperature is above 200℃,and it needs to be activated at a higher temperature to achieve the required pumping performance.
文摘监测运动负荷是运动训练、竞赛及康复训练的关键环节,是影响运动成绩和降低运动伤害的关键因素,也是训练规划的核心。训练负荷的监测通常是为了量化两个关联的联系:训练负荷—成绩关系(TL-P)和训练负荷—伤害关系(TL-I)。在对文献的系统回顾中,TL的主观测量,特别是session-RPE训练负荷量化方法(以下简称“sRPE”)的评分,被推荐为TL的主要测量方法。主观测量也可能比客观测量更敏感和一致,而且sRPE已被称为大多数运动中最常评估的TL变量。本研究运用文献资料、逻辑分析、对比分析等方法对知网、维普、web of science等国内外体育科学研究相关领域的数据库,通过综述sRPE训练负荷量化方法的概念和发展及应用于主观训练负荷监测的有效度、可靠性和局限性研究,总结该方法在当前体育科学研究中的相关研究成果和实践操作经验。
基金supported in part by the National Key R&D Program of China(2017YFA0303500)the National Natural Science Foundation of China(U1932201,21727801,and 51902303)+4 种基金the National Natural Science Foundation of China-Ministry of Foreign Affairs and International Cooperation of Italy(51861135202)CAS International Partnership Program(211134KYSB20190063)Key Research Program of Frontier Sciences(QYZDB-SSW-SLH018)the University of Science and Technology of China start-up fundCAS Interdisciplinary Innovation Team。
文摘Broadly,the oxygen evolution reaction(OER)has been deeply understood as a significant part of energy conversion and storage.Nevertheless,the anions in the OER catalysts have been neglected for various reasons such as inactive sites,dissolution,and oxidation,amongst others.Herein,we applied a model catalyst s-Ni(OH)2 to track the anionic behavior in the catalyst during the electrochemical process to fill this gap.The advanced operando synchrotron radiation Fourier transform infrared(SR-FTIR)spectroscopy,synchrotron radiation photoelectron spectroscopy(SRPES)depth detection and differential X-ray absorption fine structure(D-XAFS)spectrum jointly point out that some oxidized sulfur species(SO_(4)^(2-))will selfoptimize new Ni–S bonds during OER process.Such amazing anionic self-optimization(ASO)behavior has never been observed in the OER process.Subsequently,the optimization-derived component shows a significantly improved electrocatalytic performance(activity,stability,etc.)compared to reference catalyst Ni(OH)_(2).Theoretical calculation further suggests that the ASO process indeed derives a thermodynamically stable structure of the OER catalyst,and then gives its superb catalytic performance by optimizing the thermodynamic and kinetic processes in the OER,respectively.This work demonstrates the vital role of anions in the electrochemical process,which will open up new perspectives for understanding OER and provide some new ideas in related fields(especially catalysis and chemistry).
基金the National Natural Science Foundation of China(Nos.21473178 and 21403205)National Basic Research Program of China(No.2013CB834605)
文摘The interaction of Co with ceria thin films and its influence on the sintering behavior of Au were investigated by scanning tunneling microscopy（STM）, synchrotron radiation photoemission spectroscopy（SRPES） and X-ray photoelectron spectroscopy（XPS）. The strong interaction between Co and CeO_2（111） leads to oxidation of Co to Co^（2＋） at 300 K, accompanied by partial reduction of ceria surface at low Co coverages. Subsequent Co deposition results in an increasing fraction of metallic Co. Annealing to high temperatures induces Co^（2＋）ions diffuse into the CeO_2 film, while the small metallic Co islands agglomerate into larger ones. The bimetallic Co–Au particles were prepared by deposition of Au on the existing Co particles on ceria surfaces. The sintering behavior of Co–Au bimetallic surfaces is found to be highly determined by the stoichiometry of ceria supports. The addition of Co to the Au/CeO_2 surface suppresses the sintering of Au particles at high temperatures in comparison with that of pure Au particles. However, Au particles are less stable on the Co/CeO_（1.82） layer than on CeO_（1.82） surface.
