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实验室光源的微束X射线荧光成像系统研制及应用研究
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作者 张文星 陶芬 +1 位作者 刘一 邓彪 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2024年第4期1061-1066,共6页
微束X射线荧光成像(μ-XRFI)是无损获取样品内部元素微区分布信息的重要方法,主要应用于微米量级区域内的元素分辨成像。同步辐射是μ-XRFI的理想光源,由于其装置庞大、造价高昂,用户机时紧张,并不适宜于常规应用。基于实验室X射线光管... 微束X射线荧光成像(μ-XRFI)是无损获取样品内部元素微区分布信息的重要方法,主要应用于微米量级区域内的元素分辨成像。同步辐射是μ-XRFI的理想光源,由于其装置庞大、造价高昂,用户机时紧张,并不适宜于常规应用。基于实验室X射线光管、多毛细管聚焦镜、高精度样品台及硅漂移探测器,研制了一套具有元素分辨的μ-XRFI系统,性能测试结果表明该系统可以测量分析元素含量为0.001%量级的溶液样品和优于20μm的空间分辨能力。基于该μ-XRFI系统开展了应用研究,获得了小鼠脑、芯片及古代陶瓷样品中的多种主要元素及微量元素的空间分布,结果表明该系统可满足μ-XRFI的需求,可为生物医学、电子元件检测、瓷器色彩成分鉴定等领域研究提供帮助。 展开更多
关键词 实验室x射线光管 多毛细管聚焦镜 荧光成像 元素分辨
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硬X射线调制望远镜卫星系统级测试设计与实现
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作者 王清泉 罗荣蒸 +3 位作者 封硕 高英伟 文向阳 徐玉朋 《航天器工程》 CSCD 北大核心 2018年第5期156-161,共6页
归纳了硬X射线调制望远镜(HXMT)卫星的系统级测试特点,其中惯性空间动中探测与X射线望远镜性能测试为相对传统遥感卫星特有的测试需求。提出了适用于HXMT卫星系统级测试的动中探测姿态机动测试方案,通过设计GPS动态仿真模拟器和星地高... 归纳了硬X射线调制望远镜(HXMT)卫星的系统级测试特点,其中惯性空间动中探测与X射线望远镜性能测试为相对传统遥感卫星特有的测试需求。提出了适用于HXMT卫星系统级测试的动中探测姿态机动测试方案,通过设计GPS动态仿真模拟器和星地高精度时间统一实现姿态机动闭环测试系统;提出了X射线光管打靶测试方案,利用靶板上不同金属材料的荧光效应产生不同谱段特征的X射线,并对热试验罐内测试进行了针对性设计。整星测试结果表明:测试系统设计合理可行,有效验证了HXMT卫星各项功能、性能指标的正确性,可为后续空间射线探测科学卫星开展系统级测试设计提供参考。 展开更多
关键词 x射线调制望远镜卫星 系统级测试 动中探测 x射线光管打靶
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X射线管故障分析及使用维护
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作者 王振丰 《设备管理与维修》 2006年第1期22-22,共1页
X射线管灯丝烧断原因有:灯丝本身损耗、X射线管的高压真空破坏、铍窗漏气。使用与维护中注意,超过1h不用仪器时,将X射线管设置为待机状态;超过两星期不用仪器时,将X射线管高压关闭;超过十星期不用仪器时,将X射线管拆下,千万不要通过关... X射线管灯丝烧断原因有:灯丝本身损耗、X射线管的高压真空破坏、铍窗漏气。使用与维护中注意,超过1h不用仪器时,将X射线管设置为待机状态;超过两星期不用仪器时,将X射线管高压关闭;超过十星期不用仪器时,将X射线管拆下,千万不要通过关闭冷却水去关闭X射线管高压。探讨延长X射线管使用寿命和保证其正常使用的一般原则。 展开更多
关键词 x射线光管 故障分析 使用维护
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基于Opera的微焦点场发射电子枪仿真实验 被引量:4
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作者 王小菊 查林宏 +2 位作者 祁康成 曹贵川 陆荣国 《实验技术与管理》 CAS 北大核心 2019年第12期98-101,106,共5页
对基于X射线管的微焦点场发射电子枪,提出了一套完整的虚拟仿真实验方案。利用计算机模拟软件Opera-3D对电子枪结构进行建模,重点研究栅极形状、栅极电压、栅极-聚焦极间距、聚焦极形状等参数对电子束流及束斑的影响,优化后的仿真结果... 对基于X射线管的微焦点场发射电子枪,提出了一套完整的虚拟仿真实验方案。利用计算机模拟软件Opera-3D对电子枪结构进行建模,重点研究栅极形状、栅极电压、栅极-聚焦极间距、聚焦极形状等参数对电子束流及束斑的影响,优化后的仿真结果满足设计指标。通过该仿真实验,学生可以深入理解电子发射的基本原理和电子光学理论,为今后学习相关专业课程奠定基础。 展开更多
关键词 x光管(射线管) 微焦点 电子枪 仿真实验 OPERA
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Electrochemical reduction of CO_2 to CO using graphene oxide/carbon nanotube electrode in ionic liquid/acetonitrile system 被引量:6
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作者 Qinggong Zhu Jun Ma +4 位作者 Xinchen Kang Xiaofu Sun Jiayin Hu Guanying Yang Buxing Han 《Science China Chemistry》 SCIE EI CAS CSCD 2016年第5期551-556,共6页
Electrochemical reduction of CO_2 to CO is an interesting topic. In this work, we prepared metal-free electrodes by depositing graphene oxide(GO), multi-walled carbon nanotube(MWCNT), and GO/MWCNT composites on carbon... Electrochemical reduction of CO_2 to CO is an interesting topic. In this work, we prepared metal-free electrodes by depositing graphene oxide(GO), multi-walled carbon nanotube(MWCNT), and GO/MWCNT composites on carbon paper(CP) using electrophoretic deposition(EPD) method. The electrodes were characterized by different methods, such as X-ray diffraction(XRD) and X-ray photoelectron spectroscopy(XPS). The electrochemical reduction of CO_2 to CO was conducted on the electrodes in 1-butyl-3-methylimidazolium tetrafluoroborate([Bmim]BF4)/acetonitrile(Me CN) electrolyte, and the composition of the electrolyte influenced the reaction significantly. It was demonstrated that GO/MWCNT-CP electrode was very effective for the reaction in IL(90 wt%)/Me CN binary mixture, the Faradaic efficiency of CO and current density were even higher than those on Au and Ag electrodes in the same electrolyte. 展开更多
关键词 carbon dioxide electrochemical reduction carbon monoxide electrophoretic deposition carbon based materials
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Growth and optical properties of Dy^(3+)/Eu^(3+) co-doped NaYF_4 single crystals with cubic lattice for white LED application
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作者 江东升 姜永章 +5 位作者 夏海平 张加忠 杨硕 谷雪梅 江浩川 陈宝玖 《Optoelectronics Letters》 EI 2015年第5期356-360,共5页
Dy3+/Eu3+ co-doped cubic lattice Na YF4 single crystal with high quality in the size of ~Φ1.0 cm×10.0 cm was grown by an improved Bridgman method using potassium fluoride(KF) as assistant flux. X-ray diffraction... Dy3+/Eu3+ co-doped cubic lattice Na YF4 single crystal with high quality in the size of ~Φ1.0 cm×10.0 cm was grown by an improved Bridgman method using potassium fluoride(KF) as assistant flux. X-ray diffraction(XRD), absorption spectra, excitation spectra and emission spectra are measured to investigate the phase and luminescent properties of the crystal. The effects of excitation wavelength and concentrations of Dy3+ and Eu3+ ions on the luminescent characteristics are analyzed. The Na YF4 single crystal with the doping molar concentrations of 1.205% Dy3+ and 0.366% Eu3+ exhibits an excellent white light emission with chromaticity coordinates of x=0.321, y=0.332. It indicates that the Dy3+/Eu3+ co-doped cubic lattice Na YF4 single crystal can be a potential luminescent material for the ultraviolet(UV) light excited white light emitting diode(w-LED). 展开更多
关键词 cubic Eu luminescent Bridgman coordinates excitation ultraviolet doping potassium fluoride
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Functionalized, carbon nanotube material for the catalytic degradation of organophosphate nerve agents
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作者 Mark M. Bailey John M. Heddleston +2 位作者 Jeffrey Davis Jessica L. Staymates Angela R. Hight Walker 《Nano Research》 SCIE EI CAS CSCD 2014年第3期390-398,共9页
Recent world events have emphasized the need to develop innovative, functional materials that will safely neutralize chemical warfare (CW) agents in situ to protect military personnel and civilians from dermal expos... Recent world events have emphasized the need to develop innovative, functional materials that will safely neutralize chemical warfare (CW) agents in situ to protect military personnel and civilians from dermal exposure. Here, we demonstrate the efficacy of a novel, proof-of-concept design for a Cu-containing catalyst, chemically bonded to a single-wall carbon nanotube (SWCNT) structural support, to effectively degrade an organophosphate simulant. SWCNTs have high tensile strength and are flexible and light-weight, which make them a desirable structural component for unique, fabric-like materials. This study aims to develop a self-decontaminating, carbon nanotube-derived material that can ultimately be incorporated into a wearable fabric or protective material to minimize dermal exposure to organophosphate nerve agents and to prevent accidental exposure during decontamination procedures. Carboxylated SWCNTs were functionalized with a polymer, which contained Cu-chelating bipyridine groups, and their catalytic activity against an organophosphate simulant was measured over time. The catalytically active, functionalized nanomaterial was characterized using X-ray fluorescence and Raman spectroscopy. Assuming zeroth-order reaction kinetics, the hydrolysis rate of the organophosphate simulant, as monitored by UV-vis absorption in the presence of the catalytically active nanomaterial, was 63 times faster than the uncatalyzed hydrolysis rate for a sample containing only carboxylated SWCNTs or a control sample containing no added nanotube materials. 展开更多
关键词 single-wall carbonnanotubefunctionalization catalytically-activenanomaterial chemical warfare agent
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