The synchrotron radiation beamline BL17B of the National Facility for Protein Science(NFPS)in Shanghai,situated at the Shanghai Synchrotron Radiation Facility(SSRF),was originally designed for diffraction experiments ...The synchrotron radiation beamline BL17B of the National Facility for Protein Science(NFPS)in Shanghai,situated at the Shanghai Synchrotron Radiation Facility(SSRF),was originally designed for diffraction experiments and accommodates techniques including single-crystal diffraction,powder diffraction,and grazing-incidence wide-angle X-ray scattering(GIWAXS)to enable the characterization of long-range ordered atomic structures.The academic community associated with BL17B engages in research domains encompassing biology,environment,energy,and materials,and a pronounced demand for characterizing short-range ordered structures exists.To address these requirements,BL17B established an advanced X-ray absorption fine structure(XAFS)experimental platform that enabled it to address a wide range of systems,from crystalline to amorphous and from long-range order to short-range order.The XAFS platform allows simultaneous XAFS data acquisition for both the transmission and fluorescence modes within an energy range of 5-23 keV,encompassing the K-edges of titanium to ruthenium and the L3-edges of cesium to bismuth.The platform exemplifies high levels of automation achieved through automated sample assessment and data collection based on large-capacity sample wheels that facilitate remote sample loading.When integrated with a highly integrated control system that simplifies experimental preparation and data collection,the XAFS platform significantly bolsters experimental efficiency and enhances user experience.Notably,the platform boasts an impressively low extended X-ray absorption fine structure(EXAFS)detection limit of 0.04 wt%for dilute copper phthalocyanine(CuPc)samples and an even more remarkable X-ray absorption near edge structure(XANES)detection threshold of 0.01 wt%.These results demonstrate the methodology?s reliability in low-concentration sample analysis,confirming its capability to generate high-quality XAFS data.展开更多
To achieve selective leaching of ion adsorption rare earth,it is necessary to thoroughly reveal the differences in the adsorption mechanisms of aluminum and rare earth elements.In this study,we investigated the adsorp...To achieve selective leaching of ion adsorption rare earth,it is necessary to thoroughly reveal the differences in the adsorption mechanisms of aluminum and rare earth elements.In this study,we investigated the adsorption processes of Dy and Al on the surface of K–homoionic kaolinite using batch experiments and sequential chemical extractions.The results revealed that the adsorption of Dy and Al,as well as the desorption of K,followed the Langmuir model.The maximum ion-exchangeable capacity of Dy was higher(9.39 mmol.kg^(-1))than that of Al(6.30 mmol.kg^(-1)).The ion exchange stoichiometry ratios of Dy–K and Al–K derived from the Langmuir model were2.0 and 2.6.The analysis of X-ray absorption fine structure(XAFS)and density functional theory(DFT)revealed that Dy and Al were adsorbed onto kaolinite as outer-sphere hydrated complexes via hydrogen bonds.Dy was adsorbed as[Dy(H_(2)O)_(10)]^(3+),and Al was adsorbed as[Al(OH)_(2)(H_(2)O)_(4)]^(+).In particular,the adsorption of Al resulted in protonation of the hydroxyl groups on the surface of the kaolinite.Based on the above insights,the higher ion exchange stoichiometry ratios are attributed to closer adsorption distances(6.04 A for Dy and 3.69 A for Al)and lower adsorption energies(-223.72 kJ.mol^(-1)for Dy and-268.33 kJ.mol^(-1)for Al).The maximum ionexchangeable capacity is related to the change of the surface electrical properties of kaolinite.The zeta potential was increased to-7.3 mV as the protonation resulted from aluminum adsorption,while Dy adsorption had a minor effect,maintaining a value of-17.5 m V.展开更多
本文介绍应用Labview软件、气体电离室、电流放大器及数据采集卡等仪器设备构成的同步辐射XAFS(X-ray absorption fine structure)光束线站(BL14W1)数据采集系统。该系统利用NI公司开发的新模块DSC module(Datalogging and Supervisory ...本文介绍应用Labview软件、气体电离室、电流放大器及数据采集卡等仪器设备构成的同步辐射XAFS(X-ray absorption fine structure)光束线站(BL14W1)数据采集系统。该系统利用NI公司开发的新模块DSC module(Datalogging and Supervisory Control Module),实现了在Labview和EPICS(Experimental and Physics Industrial Control System)两个软件系统间数据的快速交换,使光束线控制的标准化和实验站用途的多样化有机结合。用Labview编写了数据采集软件,使该线站成功实现步进(step-by-step)模式和快扫(QXAFS)模式下的XAFS谱的采集。展开更多
红绿彩瓷是一种低温釉上彩瓷,从结构层次探讨其釉上红彩、绿彩、黄彩的呈色机理一直是古陶瓷研究的空白。采用X射线吸收精细结构(X-rayabsorption fine structure,XAFS)方法,测试分析红绿彩瓷中的红彩、绿彩和黄彩。结果表明,红彩中致...红绿彩瓷是一种低温釉上彩瓷,从结构层次探讨其釉上红彩、绿彩、黄彩的呈色机理一直是古陶瓷研究的空白。采用X射线吸收精细结构(X-rayabsorption fine structure,XAFS)方法,测试分析红绿彩瓷中的红彩、绿彩和黄彩。结果表明,红彩中致色元素Fe主要为+3价,其局域结构与Fe2O3相近,最近邻配位为扭曲的八面体结构。透射电子显微分析证实其物相为氧化铁晶体。黄彩中致色元素Fe主要存在+2价和+3价,绿彩中致色元素Cu主要为+2价,两者均处于无序度较高的局域环境中,最近邻配位为O原子。展开更多
基金supported by the Chinese Academy of Science(CAS)Key Technology Talent Program(No.2021000022)。
文摘The synchrotron radiation beamline BL17B of the National Facility for Protein Science(NFPS)in Shanghai,situated at the Shanghai Synchrotron Radiation Facility(SSRF),was originally designed for diffraction experiments and accommodates techniques including single-crystal diffraction,powder diffraction,and grazing-incidence wide-angle X-ray scattering(GIWAXS)to enable the characterization of long-range ordered atomic structures.The academic community associated with BL17B engages in research domains encompassing biology,environment,energy,and materials,and a pronounced demand for characterizing short-range ordered structures exists.To address these requirements,BL17B established an advanced X-ray absorption fine structure(XAFS)experimental platform that enabled it to address a wide range of systems,from crystalline to amorphous and from long-range order to short-range order.The XAFS platform allows simultaneous XAFS data acquisition for both the transmission and fluorescence modes within an energy range of 5-23 keV,encompassing the K-edges of titanium to ruthenium and the L3-edges of cesium to bismuth.The platform exemplifies high levels of automation achieved through automated sample assessment and data collection based on large-capacity sample wheels that facilitate remote sample loading.When integrated with a highly integrated control system that simplifies experimental preparation and data collection,the XAFS platform significantly bolsters experimental efficiency and enhances user experience.Notably,the platform boasts an impressively low extended X-ray absorption fine structure(EXAFS)detection limit of 0.04 wt%for dilute copper phthalocyanine(CuPc)samples and an even more remarkable X-ray absorption near edge structure(XANES)detection threshold of 0.01 wt%.These results demonstrate the methodology?s reliability in low-concentration sample analysis,confirming its capability to generate high-quality XAFS data.
基金financially supported by the National Key Research and Development Program of China(No.2021YFC2902203)the Key Research and Development Program of Guangxi Province(No.Guike-AB22080056)+2 种基金Beijing Nova Program(No.20230484379)the Science and Technology Innovation Fund of GRINM(No.2022PD0102)the Central Government Guides Local Science and Technology Development Fund Project(No.246Z4005G)。
文摘To achieve selective leaching of ion adsorption rare earth,it is necessary to thoroughly reveal the differences in the adsorption mechanisms of aluminum and rare earth elements.In this study,we investigated the adsorption processes of Dy and Al on the surface of K–homoionic kaolinite using batch experiments and sequential chemical extractions.The results revealed that the adsorption of Dy and Al,as well as the desorption of K,followed the Langmuir model.The maximum ion-exchangeable capacity of Dy was higher(9.39 mmol.kg^(-1))than that of Al(6.30 mmol.kg^(-1)).The ion exchange stoichiometry ratios of Dy–K and Al–K derived from the Langmuir model were2.0 and 2.6.The analysis of X-ray absorption fine structure(XAFS)and density functional theory(DFT)revealed that Dy and Al were adsorbed onto kaolinite as outer-sphere hydrated complexes via hydrogen bonds.Dy was adsorbed as[Dy(H_(2)O)_(10)]^(3+),and Al was adsorbed as[Al(OH)_(2)(H_(2)O)_(4)]^(+).In particular,the adsorption of Al resulted in protonation of the hydroxyl groups on the surface of the kaolinite.Based on the above insights,the higher ion exchange stoichiometry ratios are attributed to closer adsorption distances(6.04 A for Dy and 3.69 A for Al)and lower adsorption energies(-223.72 kJ.mol^(-1)for Dy and-268.33 kJ.mol^(-1)for Al).The maximum ionexchangeable capacity is related to the change of the surface electrical properties of kaolinite.The zeta potential was increased to-7.3 mV as the protonation resulted from aluminum adsorption,while Dy adsorption had a minor effect,maintaining a value of-17.5 m V.
文摘本文介绍应用Labview软件、气体电离室、电流放大器及数据采集卡等仪器设备构成的同步辐射XAFS(X-ray absorption fine structure)光束线站(BL14W1)数据采集系统。该系统利用NI公司开发的新模块DSC module(Datalogging and Supervisory Control Module),实现了在Labview和EPICS(Experimental and Physics Industrial Control System)两个软件系统间数据的快速交换,使光束线控制的标准化和实验站用途的多样化有机结合。用Labview编写了数据采集软件,使该线站成功实现步进(step-by-step)模式和快扫(QXAFS)模式下的XAFS谱的采集。
文摘红绿彩瓷是一种低温釉上彩瓷,从结构层次探讨其釉上红彩、绿彩、黄彩的呈色机理一直是古陶瓷研究的空白。采用X射线吸收精细结构(X-rayabsorption fine structure,XAFS)方法,测试分析红绿彩瓷中的红彩、绿彩和黄彩。结果表明,红彩中致色元素Fe主要为+3价,其局域结构与Fe2O3相近,最近邻配位为扭曲的八面体结构。透射电子显微分析证实其物相为氧化铁晶体。黄彩中致色元素Fe主要存在+2价和+3价,绿彩中致色元素Cu主要为+2价,两者均处于无序度较高的局域环境中,最近邻配位为O原子。
