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Test of a High Throughput Detector on the X-ray Crystal Spectrometer of the EAST 被引量:1
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作者 吕波 石跃江 +9 位作者 王福地 万宝年 Manfred BITTER Kenneth W. HILL Sang-gon LEE 李颖颖 符佳 张继宗 徐经翠 沈永才 《Plasma Science and Technology》 SCIE EI CAS CSCD 2013年第2期97-100,共4页
An attempt was made to improve the spatio-temporal resolution of the tangen- tial X-ray crystal spectrometer (XCS) on the Experimental Advanced Superconducting Tokamak (EAST) by evaluating experimentally the appli... An attempt was made to improve the spatio-temporal resolution of the tangen- tial X-ray crystal spectrometer (XCS) on the Experimental Advanced Superconducting Tokamak (EAST) by evaluating experimentally the applicability of a novel X-ray photon detection tech- nology for measuring the satellite spectra of Ar XVII with a high counting rate. High-resolution experimental data on the profiles of ion temperature and plasma rotation velocity facilitate the studies of the mechanisms underlining important physical phenomena, such as plasma heating, L-H transition and momentum transport. Based on silicon diode array and single-photon counting technology, a relatively small area (83.8 x 33.5 mm~) two-dimensional detector was successfully in- stalled and tested in the recent EAST campaign. X-ray photon counting rate higher than 20 MHz was observed for the first time, and high quality satellite spectra were recorded for ion temperature and plasma rotation measurement, indicating that the new technology is suitable for the next-step high-resolution XCS on EAST, and the deployment of a detector array with a much larger X-ray sensing area is planned for better plasma coverage. 展开更多
关键词 x-ray crystal spectrometer high resolution ion temperature plasma rotation
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Measurement of tungsten impurity spectra with a two-crystal X-ray crystal spectrometer on EAST
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作者 Liang HE Jun CHEN +12 位作者 Fudi WANG Jinjia CAO Hongming ZHANG Jia FU Yingying LI Yichao LI Bin BIN Qingjiang YU Shunkuan WAN Jin YANG Xunyu WANG Bo LYU Xueyu GONG 《Plasma Science and Technology》 SCIE EI CAS CSCD 2020年第8期14-19,共6页
Spectral measurement of tungsten(W)impurity is essential to study impurity transport.Therefore,an X-ray crystal spectrometer(XCS)on EAST was used to measure the line spectra from highly ionized W ions.On EAST,both pol... Spectral measurement of tungsten(W)impurity is essential to study impurity transport.Therefore,an X-ray crystal spectrometer(XCS)on EAST was used to measure the line spectra from highly ionized W ions.On EAST,both poloidal XCS and tangential XCS have been developed to measure the plasma temperature as well as the rotation velocity.Recently,He-like and H-like argon spectra have also been obtained using a two-crystal setup.W lines are identified in this study.Through a careful analysis,the W lines of 3.9336,3.9321,and 3.664(A)are found to be diffracted by He-like or H-like crystals.The lines are confirmed with the NIST database.We also calculated the ion temperature with Doppler broadening of these lines.The ion temperature from the W lines is entirely consistent with that from Ar line spectra.The measurement of these W line spectra could be used to study W impurity transport in future work. 展开更多
关键词 TUNGSTEN SPECTRA x-ray crystal spectrometer two-crystal
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A High-Efficiency X-Ray Crystal Spectrometer for X-Ray Thomson Scattering
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作者 张小丁 张继彦 +4 位作者 杨国洪 韦敏习 胡广月 赵斌 郑坚 《Plasma Science and Technology》 SCIE EI CAS CSCD 2013年第8期755-759,共5页
Highly oriented pyrolitic graphite (HOPG) has high X-ray diffraction efficiency due to its unique mosaic crystal structure, and thus is very suitable for its application to X-ray Thomson scattering measurement of so... Highly oriented pyrolitic graphite (HOPG) has high X-ray diffraction efficiency due to its unique mosaic crystal structure, and thus is very suitable for its application to X-ray Thomson scattering measurement of solid-density plasmas. In this article, by using the K-shell X-ray source from laser-produced Ti plasma, the properties of the HOPG spectrometer are characterized and compared with those of the flat Pentaerythritol (PET) spectrometer. The results show that the diffraction efficiency of the HOPG spectrometer under focusing condition is an order higher than that of the PET spectrometer, while the spectral resolution of the HOPG is about 320, high enough to be used in the measurement of X-ray Thomson scattering spectra. 展开更多
关键词 crystal spectrometer highly oriented pyrolytic graphite x-ray Thomson scattering
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Inversion techniques to obtain local rotation velocity and ion temperature profiles for the x-ray crystal spectrometer on EAST
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作者 林子超 张洪明 +7 位作者 王福地 Cheonho BAE 符佳 金仡飞 卢迪安 傅盛宇 李建康 吕波 《Plasma Science and Technology》 SCIE EI CAS CSCD 2023年第9期26-33,共8页
Inversion techniques are conducted based on the tangential x-ray crystal spectroscopy(TXCS)geometry on EAST to obtain the local profiles of ion temperature(Ti)and toroidal rotation velocity(vt).Firstly,local emissivit... Inversion techniques are conducted based on the tangential x-ray crystal spectroscopy(TXCS)geometry on EAST to obtain the local profiles of ion temperature(Ti)and toroidal rotation velocity(vt).Firstly,local emissivity profiles of the impurity argon are obtained using the asymmetrical Abel inversion.Then,the local vt and Ti profiles are calculated by considering the local emissivity profiles and the TXCS detailed geometry.In addition,how the changes in the vt profiles affect the accuracy in the Ti profiles is discussed in detail.It is also found that the lineintegrated Ti profiles are becoming less accurate with the increase in the radial gradient in the local vt profiles.Nonetheless,accurate Ti radial profiles are reconstructed after considering the effects of the emissivity and velocity,which are verified by comparing the inverted vt and Ti profiles with those local profile measurements from the Charge eXchange Recombination Spectroscopy(CXRS)on EAST. 展开更多
关键词 plasma toroidal rotation ion temperature x-ray crystal spectroscopy Abel inversion
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A seven-crystal spectrometer for high-energy resolution X-ray spectroscopy at Shanghai Synchrotron Radiation Facility
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作者 Bing-Bao Mei Liang-Xin Wang +6 位作者 Song-Qi Gu Xiao-Zhi Su Shuo Zhang Yao Wei Jing-Yuan Ma Zheng Jiang Fei Song 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第9期82-91,共10页
A Johann-type X-ray spectrometer was successfully developed at the hard X-ray branch(in-vacuum undulator with a 24-mm periodic length)of the energy material beamline(E-line)at the Shanghai Synchrotron Radiation Facili... A Johann-type X-ray spectrometer was successfully developed at the hard X-ray branch(in-vacuum undulator with a 24-mm periodic length)of the energy material beamline(E-line)at the Shanghai Synchrotron Radiation Facility(SSRF).This spectrometer was utilized to implement X-ray emission spectroscopy(XES),high-energy resolution fluorescence-detected X-ray absorption spectroscopy(HERFD-XAS),and resonant inelastic X-ray scattering.Seven spherically bent crystals were positioned on the respective vertical 500-mm-diameter Rowland circles,adopting an area detector to increase the solid angle to 1.75%of 4πsr,facilitating the study of low-concentrate systems under complex reaction conditions.Operated under the atmosphere pressure,the spectrometer covers the energy region from 3.5 to 18 keV,with the Bragg angle ranging from 73°to 86°during vertical scanning.It offers a promised energy resolution of sub-eV(XES)and super-eV(HERFD-XAS).Generally,these comprehensive core-level spectroscopy methods based on hard X-rays at the E-line with an extremely high photon flux can meet the crucial requirements of a green energy strategy.Moreover,they provide substantial support for scientific advances in fundamental research. 展开更多
关键词 x-ray emission spectroscopy High-energy-resolution x-ray spectrometer Johann geometry Energy materials SSRF
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Improvement of Lattice Parameter Accuracy in Single Crystal XRD Based on a Laser-Induced X-Ray Source
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作者 LIU Jin WANG Qiannan LI Jiangtao 《高压物理学报》 北大核心 2025年第4期9-15,共7页
The lattice parameter,measured with sufficient accuracy,can be utilized to evaluate the quality of single crystals and to determine the equation of state for materials.We propose an iterative method for obtaining more... The lattice parameter,measured with sufficient accuracy,can be utilized to evaluate the quality of single crystals and to determine the equation of state for materials.We propose an iterative method for obtaining more precise lattice parameters using the interaction points for the pseudo-Kossel pattern obtained from laser-induced X-ray diffraction(XRD).This method has been validated by the analysis of an XRD experiment conducted on iron single crystals.Furthermore,the method was used to calculate the compression ratio and rotated angle of an LiF sample under high pressure loading.This technique provides a robust tool for in-situ characterization of structural changes in single crystals under extreme conditions.It has significant implications for studying the equation of state and phase transitions. 展开更多
关键词 lattice parameter measurement accuracy single crystal x-ray diffraction iterative algorithm high pressure ratio of compression
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Optimized online filter stack spectrometer for ultrashort X-ray pulses
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作者 Jia-Xing Wen Ge Ma +17 位作者 Ming-Hai Yu Yu-Chi Wu Yong-Hong Yan Shao-Yi Wang Huai-Zhong Gao Lu-Shan Wang Yu-Gang Zhou Qiang Li Yue Yang Fang Tan Xiao-Hui Zhang Jie Zhang Wen-Bo Mo Jing-Qin Su Wei-Min Zhou Yu-Qiu Gu Ming Zeng Zong-Qing Zhao 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第5期85-98,共14页
Currently,with the advent of high-repetition-rate laser-plasma experiments,the demand for online diagnosis for the X-ray spectrum is increasing because the laser-plasma-generated X-ray spectrum is very important for c... Currently,with the advent of high-repetition-rate laser-plasma experiments,the demand for online diagnosis for the X-ray spectrum is increasing because the laser-plasma-generated X-ray spectrum is very important for characterizing electron dynamics and applications.In this study,scintillators and silicon PIN(P-type–intrinsic-N-type semiconductor)diodes were used to construct a wideband online filter stack spectrometer.The X-ray sensor and filter arrangement was optimized using a genetic algorithm to minimize the condition number of the response matrix.Consequently,the unfolding error was significantly reduced based on numerical experiments.The detector responses were quantitatively calibrated by irradiating the scintillator and PIN diode with various nuclides and comparing the measuredγ-ray peaks.A prototype 15-channel spectrometer was developed by integrating an X-ray detector with front-and back-end electronics.The prototype spectrometer could record X-ray pulse signals at a repetition rate of 1 kHz.Furthermore,an optimized spectrometer was employed to record the real-time spectra of laser-driven bremsstrahlung sources.This optimized spectrometer offers a compact solution for spectrum diagnostics of ultrashort X-ray pulses,exhibiting improved accuracy in terms of spectrum measurements and repetition rates,and could be widely used in next-generation high-repetition-rate high-power laser facilities. 展开更多
关键词 Filter stack spectrometer Laser plasma diagnostics x-ray diagnostics Scintillator PIN diode
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Measurement of impurity lines with two-crystal x-ray spectrometers on EAST
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作者 Xinshuai YANG Ruiji HU +7 位作者 Jun CHEN Fudi WANG Jia FU Yingying LI Hongming ZHANG Yongcai SHEN Xianghui YIN Bo LYU 《Plasma Science and Technology》 SCIE EI CAS CSCD 2018年第12期1-8,共8页
To simultaneously measure the He-like and H-like argon spectra, a two-crystal assembly has been deployed to replace the previous single crystal on the tangential x-ray crystal spectrometer.By selecting appropriate cry... To simultaneously measure the He-like and H-like argon spectra, a two-crystal assembly has been deployed to replace the previous single crystal on the tangential x-ray crystal spectrometer.By selecting appropriate crystals with similar Bragg angles, plasma temperature in the range of 0.5 keV≤Te≤10 keV and rotation can be diagnosed based on the He-like and H-like argon spectra. However, due to the added complexity in the two-crystal assembly in which the spectra might be diffracted by two crystals, some additional impurity lines were identified. For example,tungsten(W) lines in different ionization states were diffracted by the He-like and H-like crystal.Additional molybdenum(Mo) lines in the wavelength range of He-like and H-like argon spectra lines were also summarized. The existence of these additional lines caused the fitted temperature to be different from the true values. This paper presents the identified lines through a comparison with available database, which should be included in the fitting procedure. 展开更多
关键词 plasma diagnostics x-ray two-crystal spectrometer Doppler broadening dielectronicsatellite
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A New Method for Measurements of the Poloidal Rotation Velocities and Wavelength Calibration of X-ray Imaging Crystal Spectrometer in Magnetic Fusion Devices
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作者 石跃江 吕波 +3 位作者 王福地 M.BITTER K.W.HILL 叶民友 《Plasma Science and Technology》 SCIE EI CAS CSCD 2015年第4期265-267,共3页
A new simple method is presented for the wavelength calibration and measurement of poloidal rotation velocities with X-ray imaging crystal spectrometer(XICS)in magnetic fusion devices.In this method,the toroidal rot... A new simple method is presented for the wavelength calibration and measurement of poloidal rotation velocities with X-ray imaging crystal spectrometer(XICS)in magnetic fusion devices.In this method,the toroidal rotation of plasma is applied for high precise alignment and wavelength calibration of the poloidal XICS.The measurement threshold of poloidal rotation velocity can be lowered to 1-3 km/s with this method. 展开更多
关键词 x-ray imaging crystal spectrometer wavelength calibration poloidal rotation velocity
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Design and calibration of an elliptical crystal spectrometer for the diagnosis of proton-induced x-ray emission(PIXE)
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作者 方言律 李东彧 +9 位作者 程浩 高原 申泽清 杨童 李昱泽 夏亚东 晏炀 颜莎 林晨 颜学庆 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第11期220-225,共6页
Laser-driven proton-induced x-ray emission(laser-PIXE) is a nuclear analysis method based on the compact laser ion accelerator. Due to the transient process of ion acceleration, the laser-PIXE signals are usually spur... Laser-driven proton-induced x-ray emission(laser-PIXE) is a nuclear analysis method based on the compact laser ion accelerator. Due to the transient process of ion acceleration, the laser-PIXE signals are usually spurted within nanoseconds and accompanied by strong electromagnetic pulses(EMP), so traditional multi-channel detectors are no longer applicable.In this work, we designed a reflective elliptical crystal spectrometer for the diagnosis of laser-PIXE. The device can detect the energy range of 1 keV–11 ke V with a high resolution. A calibration experiment was completed on the electrostatic accelerator of Peking University using samples of Al, Ti, Cu, and ceramic artifacts. The detection efficiency of the elliptical crystal spectrometer was obtained in the order of 10-9. 展开更多
关键词 elliptical crystal spectrometer proton-induced x-ray emission applications of laser ion accelera-tion
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High-precision X-ray polarimeter based on channel-cut crystals
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作者 Shang-Yu Si Zhong-Liang Li +8 位作者 Wen-Hong Jia Lian Xue Hong-Xin Luo Jian-Cai Xu Bai-Fei Shen Lin-Gang Zhang Liang-Liang Ji Yu-Xin Leng Ren-Zhong Tai 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第3期30-39,共10页
We report on using synthetic silicon for a high-precision X-ray polarimeter comprising a polarizer and an analyzer,each based on a monolithic channel-cut crystal used at multiple Brewster reflections with a Bragg angl... We report on using synthetic silicon for a high-precision X-ray polarimeter comprising a polarizer and an analyzer,each based on a monolithic channel-cut crystal used at multiple Brewster reflections with a Bragg angle very close to 45°.Experiments were performed at the BL09B bending magnet beamline of the Shanghai Synchrotron Radiation Facility using a Si(800)crystal at an X-ray energy of 12.914 keV.A polarization purity of 8.4×10^(-9)was measured.This result is encouraging,as the measured polarization purity is the best-reported value for the bending magnet source.Notably,this is the firstly systematic study on the hard X-ray polarimeter in China,which is crucial for exploring new physics,such as verifying vacuum birefringence. 展开更多
关键词 x-ray polarimeter Vacuum birefringence Synchrotron radiation Channel-cut crystal
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Spectrometer of hard X-ray imager payload onboard the ASO-S mission 被引量:1
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作者 Yan Zhang Jian-Hua Guo +5 位作者 Zhe Zhang Deng-Yi Chen Yi-Ming Hu Yong-Qiang Zhang Tao Ma Yong-Yi Huang 《Nuclear Science and Techniques》 SCIE CAS CSCD 2019年第8期92-99,共8页
A spaceborne hard X-ray spectrometer, composed of an array of 99 scintillation detectors and associated readout electronics, has been developed for the hard X-ray imager(HXI). The HXI is one of the three payloads onbo... A spaceborne hard X-ray spectrometer, composed of an array of 99 scintillation detectors and associated readout electronics, has been developed for the hard X-ray imager(HXI). The HXI is one of the three payloads onboard the advanced space-based solar observatory(ASO-S), which is scheduled to be launched in early 2022 as the first Chinese solar satellite. LaBr3 scintillators and photomultiplier tubes with a super bialkali cathode are used to achieve an energy resolution better than 20% at 30 keV.Further, a new multi-channel charge-sensitive readout application-specific integrated circuit guarantees high-frequency data acquisition with low power consumption. This paper presents a detailed design of the spectrometer for the engineering model of the HXI and discusses its noise and linearity performance. 展开更多
关键词 Solar radiation detection x-ray spectrometer HARD x-ray IMAGER ASO-S
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Design of Time-Resolved Shifted Dual Transmission Grating Spectrometer for the X-Ray Spectrum Diagnostics 被引量:1
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作者 王保清 易涛 +6 位作者 王传珂 朱效立 李廷帅 李晋 刘慎业 江少恩 丁永坤 《Plasma Science and Technology》 SCIE EI CAS CSCD 2016年第7期781-785,共5页
A new time-resolved shifted dual transmission grating spectrometer (SDTGS) is designed and fabricated in this work. This SDTGS uses a new shifted dual transmission grating (SDTG) as its dispersive component, which... A new time-resolved shifted dual transmission grating spectrometer (SDTGS) is designed and fabricated in this work. This SDTGS uses a new shifted dual transmission grating (SDTG) as its dispersive component, which has two sub transmission gratings with different line densities, of 2000 lines/mm and 5000 lines/mm. The axes of the two sub transmission gratings in SDTG are horizontally and vertically shifted a certain distance to measure a broad range of 0.1-5 keV time-resolved X-ray spectra. The SDTG has been calibrated with a soft X-ray beam of the synchrotron radiation facility and its diffraction efficiency is also measured. The designed SDTGS can take full use of the space on a record panel and improve the precision for measuring spatial and temporal spectrum simultaneously. It will be a promising application for accurate diagnosis of the soft X-ray spectrum in inertial confinement fusion. 展开更多
关键词 shifted dual transmission grating spectrometer GRATING x-ray spectra diag-nosis of the soft x-ray spectrum
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High performance streaked X-ray spectrometer for research of laser-produced plasmas
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作者 Guo Luting Wei Minxi +8 位作者 Hu Xin Deng Keli Chen Tao Deng Bo Zhang Lu Zhao Yang Li Jin Xiao Shaoqiu Liu Shenye 《强激光与粒子束》 EI CAS CSCD 北大核心 2016年第2期52-55,共4页
In order to mitigate the effect of the strong electromagnetic pulse, which produces laser-plasma interactions, we designed a new streaked X-ray spectrometer (SXS) enclosed within a well-sealed, electromag- netic int... In order to mitigate the effect of the strong electromagnetic pulse, which produces laser-plasma interactions, we designed a new streaked X-ray spectrometer (SXS) enclosed within a well-sealed, electromag- netic interference-free cavity. The SXS can cover a wide selection of spectral windows using interchangeable Bragg crystals and by appropriate adjustment of the Bragg angle. The SXS has been used to observe time-re- solved X-ray spectrum in the 2.5 keV to 3.5 keV photon-energy range, resulting in a demonstrated spectral res- olution of about 13 at 2960 eV with a time resolution of 10 ps. The observed time and spectral resolutions dem- onstrate the applicability of the SXS for studies of laser-produced plasmas. 展开更多
关键词 streaked x-ray spectrometer x-ray SPECTRUM PLASMAS BRAGG crystal
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Ray tracing method for the grazing incidence flat-field imaging soft X-ray spectrometer
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作者 董全力 刘运全 +2 位作者 腾浩 李英骏 张杰 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第6期392-397,共6页
A ray tracing method is introduced for helping adjustment and spectra analysis of the grazing incidence flat-field imaging soft X-ray spectrometer. For a single point source, the spectra images obtained by separate co... A ray tracing method is introduced for helping adjustment and spectra analysis of the grazing incidence flat-field imaging soft X-ray spectrometer. For a single point source, the spectra images obtained by separate components, the toroidal mirror, and the grazing incidence flat-field concave grating with varied line spaces are given respectively. The calculated spectral images of the single point source by the spectrometer are also given for comparison with measurements with different experimental alignments. 展开更多
关键词 flat-field grating spectrometer soft x-ray diagnosis
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Accuracy analysis of iron content of galvanized coating using an X-ray fluorescence spectrometer with an L-spectrum
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作者 WANG Jingjing CHEN Yanfei 《Baosteel Technical Research》 CAS 2023年第4期35-40,共6页
The accuracy(repeatability and reproducibility) of the iron content analysis of galvanized coating using an X-ray fluorescence spectrometer with an L-spectrum is not better than that of flame atomic absorption spectro... The accuracy(repeatability and reproducibility) of the iron content analysis of galvanized coating using an X-ray fluorescence spectrometer with an L-spectrum is not better than that of flame atomic absorption spectrometry, sometimes it exceeds the quality control limit.Influences, such as current, voltage, equipment(internal circulating water, 10%CH4+90%Ar, and vacuum) checking, instrument monitoring, sample cleaning, and oper-ators, were investigated by means of 6-sigma and lean operations to improve accuracy. 展开更多
关键词 x-ray fluorescence spectrometer Lspectrum galvanized coating iron content
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A study on some elements and their phases in sediments of Changjiang Estuary by X-ray spectrometer and X-ray diffractometer
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作者 Han Jiancheng, Li Li, Chen Qiming, Wu Xinran, Chen Banglin and Han QingpingDepartment of Chemistry, East China Normal University, Shanghai 200062, China 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1997年第1期121-125,共5页
INTRODUCTIONThe studies on the quantitative distribution of the conventional elements and their phases in the sediments of the Changjiang Estuary are of great importance to the understanding of the chemical processes ... INTRODUCTIONThe studies on the quantitative distribution of the conventional elements and their phases in the sediments of the Changjiang Estuary are of great importance to the understanding of the chemical processes of ion exchange, absorption, desorption and flocculation in the estuary. 展开更多
关键词 A study on some elements and their phases in sediments of Changjiang Estuary by x-ray spectrometer and x-ray diffractometer
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A Reflectron Time-of-Flight Mass Spectrometer with a Nano-Electrospray Ionization Source for Study of Metal Cluster Compounds
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作者 吴小虎 谢华 +3 位作者 刘志凌 苏海峰 林水潮 唐紫超 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2016年第4期401-406,I0001,共7页
An experiment facility has been set up for the study of metal cluster compounds in our laboratory, which consists of a nano-electrospray ionization source, an ion transmission and focus system, and a reflectron time-o... An experiment facility has been set up for the study of metal cluster compounds in our laboratory, which consists of a nano-electrospray ionization source, an ion transmission and focus system, and a reflectron time-of-fight mass spectrometer. Taking advantage of the nano-electrospray ionization source, polyvalent ions are usually produced in the "ionization" process and the obtained mass resolution of the equipment is over 8000. The molecular ion peaks of metal cluster compounds [Au20(PPhpy2)10Cl2](SbF6)4, where PPhpy2=bis(2- pyridyl)phenylphosphine, and [AuaAg2(C)L6](BF4)4, where L=2-(diphenylphosphino)-5- methylpyridine, are distinguished in the respective mass spectrum, accompanied by some fragment ion peaks. In addition, the mass-to-charge ratios of the parent ions are determi- nated. Preliminary results suggest that the device is a powerful tool for the study of metal cluster compounds. It turns out that the information obtained by the instrumentation serves as an essential supplement to single crystal X-ray diffraction for structure characterization of metal cluster compounds. 展开更多
关键词 Nano-electrospray ionization source Ion transmission and focus system Reflectron time-of-flight mass spectrometer Metal cluster compounds Single crystal x-ray diffraction
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Synthesis and X-ray Crystal Structure of a New Molecular Clip 被引量:4
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作者 佘能芳 高蒙 +1 位作者 王帅 吴安心 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2008年第7期777-780,共4页
The synthesis and X-ray crystal structure of a new molecular clip 2 was reported. It (C24H24N4O2, Mr = 400.47) crystallizes in the space group C2/c with a = 15.587(2), b = 8.5805(12), c = 15.259(2) A, β = 102... The synthesis and X-ray crystal structure of a new molecular clip 2 was reported. It (C24H24N4O2, Mr = 400.47) crystallizes in the space group C2/c with a = 15.587(2), b = 8.5805(12), c = 15.259(2) A, β = 102.448(3)°, V= 1992.9 (5)A63, Z = 4, Dc = 1.335 g/cm63,μ = 0.087 mm^-1 and F(000) = 848. It remains monomeric in the crystal and a tape-like structure is formed in the crystal structure of molecular clip. The most unusual structural feature of 2 is the boat conformation of its cyclohexyl ring imposed by the ring fusion at C(9)-C(9a). 展开更多
关键词 molecular clip x-ray crystal structure boat conformation
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High-resolution x-ray monochromatic imaging for laser plasma diagnostics based on toroidal crystal 被引量:2
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作者 司昊轩 董佳钦 +3 位作者 方智恒 蒋励 伊圣振 王占山 《Plasma Science and Technology》 SCIE EI CAS CSCD 2023年第1期181-186,共6页
Monochromatic x-ray imaging is an essential method for plasma diagnostics related to density information.Large-field high-resolution monochromatic imaging of a He-like iron(Fe XXV)Kαcharacteristic line(6.701 keV)for ... Monochromatic x-ray imaging is an essential method for plasma diagnostics related to density information.Large-field high-resolution monochromatic imaging of a He-like iron(Fe XXV)Kαcharacteristic line(6.701 keV)for laser plasma diagnostics was achieved using a developed toroidal crystal x-ray imager.A high-index crystal orientation Ge(531)wafer with a Bragg angle of 75.37°and the toroidal substrate were selected to obtain sufficient diffraction efficiency and compensate for astigmatism under oblique incidence.A precise offline assembly method of the toroidal crystal imager based on energy substitution was proposed,and a spatial resolution of 3-7μm was obtained by toroidal crystal imaging of a 600 line-pairs/inch Au grid within an object field of view larger than 1.0 mm.The toroidal crystal x-ray imager has been successfully tested via side-on backlight imaging experiments of the sinusoidal modulation target and a 1000 line-pairs/inch Au grid with a linewidth of 5μm using an online alignment method based on dual positioning balls to indicate the target and backlighter.This paper describes the optical design,adjustment method,and experimental results of a toroidal crystal system in a laboratory and laser facility. 展开更多
关键词 laser plasma diagnostics toroidal crystal monochromatic x-ray imaging
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