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Nano Research 2024年第6期17卷 4943-4950页

作者： Rui Li Xiayan Yan Meng Liu Qingkai Zhao Jie Du Xinxin Tan Jingwen Ba rongguang zeng Wenhua Luo Jingsong Xu Institute of Materials China Academy of Engineering PhysicsJiangyou 621907China Science and Technology on Surface Physics and Chemistry Laboratory Jiangyou 621908China

Top-down strategy has been widely applied for synthesis of metal single atom catalysts(SACs)via converting metal nanoparticles or bulk metals into atomically dispersed ***,we report a simple electrochemical atomic migration strategy for top-down synthesis of SACs via a facile cathodic corrosion process without involving high temperature or harsh *** of metal nanoparticles on cathode are firstly disbanded under high negative voltage,and emitted into the electrolyte in the form of atomic metal anions in Zintl *** escaped atomically dispersed metal species are then oxidized by water molecules and captured by the defects on the pre-added nitrogen doped carbon carriers in the *** cathodic corrosion strategy is confirmed to be suitable for scalable synthesis of kinds of metal SACs(e.g.,Pt,Pd,and Ir)on doped carbon ***,the as-prepared nitrogen doped carbon powder supported Pt SACs exhibit superior catalytic activity toward hydrogen evolution reaction(HER)with a low overpotential of 0.024 V at 10 mA·cm^(−2)and a low Tafel slope of 29.7 mV·dec^(−1)as well as a long-term durability.

关键词： cathodic corrosion top-down strategy powdery single atom catalysts hydrogen evolution reaction scalable synthesis

Platinum single atom catalysts for hydrogen isotope separation during hydrogen evolution reaction

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Nano Research 2022年第5期15卷 3952-3958页

作者： Jingsong Xu Rui Li Xiayan Yan Qingkai Zhao rongguang zeng Jingwen Ba Qifa Pan Xin Xiang Daqiao Meng Science and Technology on Surface Physics and Chemistry Laboratory Jiangyou 621908China Institute of Materials China Academy of Engineering PhysicsJiangyou 621907China

Electrolysis of water is widely used for hydrogen isotope separation and the development of hydrogen evolution reaction(HER)catalysts with high selectivity and activity is of key ***,we propose single atom catalysts(SACs)as promising catalysts for efficient hydrogen isotope *** SACs and Pt nanoparticles(NPs)have been fabricated on nanoarray-structured nitrogen-doped graphite foil(NGF)substrate by a polyol reduction *** as prepared Pt1/NGF electrode exhibits high activity and selectivity toward HER with a low overpotential of 0.022 V at 10 mA·cm^(-2) and a high separation factor of 6.83 for hydrogen and deuterium separation,much better than Pt NPs *** functional theory(DFT)calculations ascribe the high activity and selectivity to the constructed Pt-N_(2)C_(2) *** work develops a new opportunity for the design and application of high-efficiency and stable SACs toward hydrogen isotope separation by electrolysis of water.

关键词： hydrogen isotope separation,single atom catalysts hydrogen evolution reaction polyol reduction separation factor

Cathodic corrosion as a facile and universal method for the preparation of supported metal single atoms

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Nano Research 2022年第3期15卷 1838-1844页

作者： Rui Li Jingsong Xu Qingkai Zhao Wensheng Ren rongguang zeng Qifa Pan Xiayan Yan Jingwen Ba Tao Tang Wenhua Luo Institute of Materials China Academy of Engineering PhysicsJiangyou 621907China Science and Technology on Surface Physics and Chemistry Laboratory Jiangyou 621908China

Top-down strategy has been generally adopted for preparation of metal single atom catalysts(SACs)due to the simplified synthetic process,metal economics,and scalability ***,we propose a general top-down route to convert metal nanoparticles into uniformly dispersed metal single atoms in mild electrochemical environment via a facile cathodic corrosion *** the synthetic process,Pt nanoparticles precursors are transformed into migrating Pt single atoms(Pt1)driven by a high negative potential;and subsequently these mobile Pt atoms are trapped and stabilized by N coordination sites of N-doped carbon paper(NCP).The as-prepared Pt1/NCP electrodes exhibit a superior catalytic activity toward hydrogen evolution reaction(HER)with a low overpotential of 0.022 V at 10 mA/cm^(2)and a low Tafel slope of 28.5 mV/dec as well as a long-term ***,the proposed electrochemical atomic migration strategy shows a promising generality for fabricating other metal single atoms(e.g.,Pd,Ir,Cu),which may open a new avenue for metallic SACs preparation.

关键词： top-down strategy electrochemical atomic migration cathodic corrosion nitrogen doped carbon paper metal single atoms hydrogen evolution reaction

理解教育政策的意义——质性取向在政策研究中的定位

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北京大学教育评论 2011年第1期9卷 152-180,192页

作者：曾荣光香港中文大学教育行政与政策学系

量化研究在教育政策研究的主导地位,在过去三十年受到质性研究的挑战;其中最重要的挑战就是,无论在教育政策制定、实施还是评鉴过程中,政策参与者特别是政策受众,对有关政策所赋予的主观意义对政策的成败至为重要。本文正是以教育政策... 详细信息

量化研究在教育政策研究的主导地位,在过去三十年受到质性研究的挑战;其中最重要的挑战就是,无论在教育政策制定、实施还是评鉴过程中,政策参与者特别是政策受众,对有关政策所赋予的主观意义对政策的成败至为重要。本文正是以教育政策研究中量化与质性研究取向的争论作起点,整理质性研究中三个方法学取向(现象学、语言学、诠释学)之间的关联,并尝试建构出一个整合的质性研究的指导架构,以作为质性研究在教育政策研究定位的参考。

关键词：教育政策研究质性研究主观意义政策参与者三十年现象学方法学语言学

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电化学溶出法尺寸可控合成铜基氧还原反应催化剂:从纳米粒子到原子团簇和单原子

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Science China Materials 2023年第4期66卷 1427-1434页

作者：李瑞徐劲松赵庆凯闫霞艳把静文宋雅琪曾荣光潘启发唐涛罗文华 Institute of Materials China Academy of Engineering PhysicsJiangyou 621907China Science and Technology on Surface Physics and Chemistry Laboratory Jiangyou 621908China

从纳米尺度到亚纳米尺度甚至到原子尺度的非贵金属粒子的尺寸可控合成对阐明金属催化剂对氧还原反应催化的尺寸效应有重要意义.本文中,我们提出了一种电化学溶出策略,用于在硫掺杂的还原氧化石墨烯上自上而下制备铜纳米粒子、原子簇及... 详细信息

从纳米尺度到亚纳米尺度甚至到原子尺度的非贵金属粒子的尺寸可控合成对阐明金属催化剂对氧还原反应催化的尺寸效应有重要意义.本文中,我们提出了一种电化学溶出策略,用于在硫掺杂的还原氧化石墨烯上自上而下制备铜纳米粒子、原子簇及单原子.在该方法中,首先电沉积获得铜纳米粒子(约8 nm),而后使用溶出伏安法,通过调控终止电位可控地将铜纳米粒子尺寸降低至原子簇尺度(约2 nm)和单原子尺度(<1 nm).对活性铜物种尺寸的有效调控使我们可以方便地从多尺度研究铜催化氧还原反应中的尺寸效应.结果表明,单原子铜表现出良好的氧还原反应催化性能,其半波电位为0.86 V,电子转移数为3.98,并具有长期稳定性,远优于其他大尺寸铜颗粒.这些研究结果为自上而下制备特定尺寸金属离子提供了新途径,将有利于尺寸可控氧还原电催化剂的未来设计.

关键词：单原子溶出伏安法原子簇氧还原反应原子团簇铜纳米粒子原子尺度还原氧化石墨烯

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”南浮一号”发射机

热带海洋 1985年第1期 84-87页

作者：陈韶浈曾荣光梁蔚鸿中国科学院南海海洋研究所

本发射机是为“南浮一号”二期工程研制的,用它发送自动采集来的海洋水文气象数据。一、方案的提出传送数据信号可采用现成的单边带发射机,其中发送移频键控电报的方框图如图1所示。

关键词：单边带发射机电报自动采集海洋水文二期工程电信频率键控数字调制移频键控南浮

甘肃省大锥蚤属一新种记述(蚤目:角叶蚤科)

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昆虫分类学报 1987年第4期 265-268页

作者：李贵真张荣广曾亚纯贵阳医学院甘肃省地方病防治研究所贵阳医学院

1980年6月,第二作者在甘肃省天水县麦积山针阔叶林中的岩石庙内,自复齿鼯鼠(Trogopterus xanthipes edithae) 体上采到跳蚤2,2,其中11邮寄中遗失。所余一对为大锥蚤属Macrostylophora Ewing一新种,兹描述如下。

关键词：蚤属蚤目复齿鼯鼠角叶蚤科第二作者中胸背板天水县 Ewing 积山前胸栉

The conformational states of talin autoinhibition complex and its activation under forces

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Science China(Life Sciences) 2015年第6期58卷 694-703页

作者： zeng Yan ZHANG Yong SONG XianQiang JI QingHua YE Sheng ZHANG rongguang LOU JiZhong Key Laboratory of RNA Biology Institute of Biophysics Chinese Academy of Sciences University of Chinese Academy of Sciences National Laboratory of Biomacromolecules Institute of Biophysics Chinese Academy of Sciences

Talin is an integrin-binding protein located at focal adhesion site and serves as both an adapter and a force transmitter. Its integrin binding activity is regulated by the intramolecular autoinhibition interaction between its F3 and RS domains. Here, we used atomic force microscopy to measure the strength of talin autoinhibition complex. Our results suggest that the lifetime of talin autoinhibition complex shows weak catch bond behavior and does not change significantly at smaller forces, while it drops rapidly at larger forces(>10 p N). Moreover, besides the complex conformation revealed by crystal structure, our molecular dynamics(MD) simulations indicate the possible existence of another stable conformation. Further analysis indicates that forces may regulate the equilibrium of the two stable binding states and result in the non-exponential force dependence of the binding lifetime. Our findings reveal a negative regulation mechanism on talin activation and provide a new point of view on the function of talin in focal adhesion.

关键词：稳定构象复杂受力活化分子动力学结合蛋白塔原子力显微镜力传感器

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电感耦合等离子体化学光谱法测定石油炼制催化剂中组分及杂质

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分析化学 1983年第9期 675-677页

作者：朱小帆陈淑清李荣光曾玉玲抚顺石油三厂检查科

在石油工业中,催化剂的应用是提高油品质量的关键.催化剂的分析以往仅限于重量、容量.比色分析;也有使用原子吸收分光光度分析及 X 荧光光谱分析法,但由于铝基体的严重干扰使测定仅限于少数元素.我们采用电感耦合等离子体化学光谱分析... 详细信息

在石油工业中,催化剂的应用是提高油品质量的关键.催化剂的分析以往仅限于重量、容量.比色分析;也有使用原子吸收分光光度分析及 X 荧光光谱分析法,但由于铝基体的严重干扰使测定仅限于少数元素.我们采用电感耦合等离子体化学光谱分析法对重整、加氢精制、加氢裂解等催化剂中的主要组份及杂质元素进行了同时测定,取得了良好的效果,已作为监控手段.

关键词：催化剂等离子体杂质元素基体元素检测下限

Defects inducing anomalous exciton kinetics in monolayer WS_(2)

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Nano Research 2022年第2期15卷 1616-1622页

作者： Zhe Li Yan zeng Zhenwei Ou Tianzhu Zhang rongguang Du Ke Wu Quanbing Guo Wei Jiang Yuhao Xu Tao Li Tai Min Ti Wang Hongxing Xu School of Physics and Technology Center for Nanoscience and Nanotechnologyand Key Laboratory of Artificial Micro-and Nanostructures of Ministry of EducationWuhan UniversityWuhan 430072China Institute of Microscale Optoelectronics Shenzhen UniversityShenzhen 518060China Center for Spintronics and Quantum System State Key Laboratory for Mechanical Behavior of MaterialsSchool of Materials Science and EngineeringXian Jiaotong UniversityXian 710049China

Two-dimensional(2D)transition metal dichalcogenide(TMD)has emerged as an effective optoelectronics material due to its novel optical *** the role of defects in exciton kinetics is crucial for achieving high-efficiency TMD ***,we observe defects induced anomalous power dependence exciton dynamics and spatial distribution in hexagonal heterogeneous WS_(2).With transient absorption microscopy study,we illustrate that these phenomena originate from the competition between radiative and defect-related non-radiative *** understand the physics behind this,a decay model is introduced with two defect-related channels,which demonstrates that more excitons decay through non-radiative channels in the dark region than the bright *** work reveals the mechanisms of anomalous exciton kinetics by defects and is instrumental for understanding and exploiting excitonic states in emerging 2D semiconductors.

关键词： transition metal dichalcogenides defect exciton dynamics transient absorption microscopy