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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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Characterization of single-pulse photon energy and photon energy jitter at the Shanghai soft X-ray Free-Electron Laser
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作者 Zichen Gao Yajun Tong +15 位作者 Yueran Wang Xinyuan Wang Pingping Wen Donghao Lu Xinye Yuan Difei Zhang Jingcheng Xiao Xiaokai Li Zhihao Guan Jiacheng Gu Yonggan Nie Zhi Guo Zhen Wang Chao Feng Jiadong Fan Huaidong Jiang 《Chinese Optics Letters》 SCIE EI CAS CSCD 2024年第10期106-111,共6页
The X-ray free-electron laser(XFEL),a new X-ray light source,presents numerous opportunities for scientific research.Self-amplified spontaneous emission(SASE)is one generation mode of XFEL in which each pulse is uniqu... The X-ray free-electron laser(XFEL),a new X-ray light source,presents numerous opportunities for scientific research.Self-amplified spontaneous emission(SASE)is one generation mode of XFEL in which each pulse is unique.In this paper,we propose a pinhole diffraction method to accurately determine the XFEL photon energy,pulses'photon energy jitter,and sample-to-detector distance for soft X-ray.This method was verified at Shanghai soft X-ray Free-Electron Laser(SXFEL).The measured average photon energy was 406.5 eV,with a photon energy jitter(root-mean-square)of 1.39 eV,and the sample-to-detector distance was calculated to be 16.61 cm. 展开更多
关键词 x-ray free-electron laser self-amplified spontaneous emission photon energy characterization photon energy jitter XFEL single-pulse diffraction
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Theoretical and experimental study of energy transportation and accumulation in femtosecond laser ablation on metals 被引量:1
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作者 谭新玉 张端明 +3 位作者 毛峰 李智华 易迪 章晓中 《中国有色金属学会会刊:英文版》 EI CSCD 2009年第6期1645-1650,共6页
The energy transportation and accumulation effect for femtosecond(fs)laser ablation on metal targets were studied using both theoretical and experimental methods.Using finite difference method,numerical simulation of ... The energy transportation and accumulation effect for femtosecond(fs)laser ablation on metal targets were studied using both theoretical and experimental methods.Using finite difference method,numerical simulation of energy transportation characteristics on copper target ablated by femtosecond laser was performed.Energy accumulation effects on metals of silver and copper ablated by an amplified Ti:sapphire femtosecond laser system were then studied experimentally.The simulated results show that the electrons and lattices have different temperature evolvement characteristics in the ablation stage.The electron temperature increases sharply and reaches the maximum in several femtoseconds while it needs thousands of femtoseconds for lattice to reach the maximum temperature.The experimental results show that uniform laser-induced periodic surface structures(PSS)can be formed with the appropriate pulsed numbers and laser energy density.Electron-phonon coupling coefficient plays an important role in PSS formation in different metals.Surface ripples of Cu are more pronounced than those of Au under the same laser energy density. 展开更多
关键词 激光烧蚀 能源运输 能量积累 金属钛 飞秒 实验 激光能量密度 电子温度
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Characteristics of Energy Accumulation and Release of Seismogenic Tectonics and Seismic Risk Analysis in Some Areas in the Tianshan Mountains, Xinjiang
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作者 ShenJun LiYingzhen WangYipeng 《Earthquake Research in China》 2005年第1期1-11,共11页
Comparative analysis between the quantitative data of active faults and seismicity reveals that a complete earthquake recurrence cycle includes the characteristic earthquake and the sub-maxima earthquakes in-between. ... Comparative analysis between the quantitative data of active faults and seismicity reveals that a complete earthquake recurrence cycle includes the characteristic earthquake and the sub-maxima earthquakes in-between. The magnitude of the sub-maxima events is correlated with the elapsed time of the characteristic earthquake and the slip rate of the fault. The fault displacement includes the major stick-slip generated by the characteristic earthquakes and the minor stick-slip by the sub-maxima ones. The magnitude-frequency relationship still works in the complete recurrence cycle. The energy accumulation in the cycle is divided approximately into four phases, and the seismicity differs at each phase. The relation of the maximum displacement with the average displacement of the characteristic earthquake suggests the partitioning of deformation between the characteristic and the sub-maxima earthquakes. Based on the above analysis, relevant mathematical equations are put forward for the quantitative assessment of the potential magnitude and earthquake risk of seismogenic tectonics. Tentative study has been carried out in this aspect in some areas of Tianshan. 展开更多
关键词 seismogenic tectonics energy accumulation and release seismic riskanalysis TIANSHAN
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A Preliminary Study on Seismicity and Stages of Seismic Energy Accumulation in Seismotectonic Regions of Tianshan
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作者 Li Yingzhen Shen Jun Wang Haitao 《Earthquake Research in China》 2006年第2期174-189,共16页
Using seismic parameters, the characteristics of the seismic activity in various seismotectonic regions of Tiaushan were studied in this paper. These regions are going through different stages of seismic energy accumu... Using seismic parameters, the characteristics of the seismic activity in various seismotectonic regions of Tiaushan were studied in this paper. These regions are going through different stages of seismic energy accumulation. Current seismic risk levels of these areas were analyzed synthetically by the tectonic movement rates, as well as the characteristics of the seismic activity and the recurrence intervals of strong earthquakes. We preliminarily studied the characteristics of seismic activity in different seismic energy accumulating stages. The result shows that the characteristics of the seismic activity in various seismotectonic regions of the Tiaushan area are influenced, not only by the regional tectonic movement, but also by the energy accumulating stage of various seismic tectonics. In the intense tectonic movement areas, it is important to estimate its stage of energy accumulating in order to predict the upper limit of the potential earthquake magnitude. In the less intense tectonic movement areas, the estimating of the stage of energy accumulation will help us recognize the dangerous level of the potential strong earthquake. The study shows that the seismotectonic regions in southern Tiaushan have reached the mid-stage and late-stage of energy accumulation, with a higher seismic activity and thus a higher seismic dangerous level than those in the northern and middle Tiaushan. The earthquake risk of southern Tianshan is up to Ms7.0, while that of the middle Tiaushan is up to Ms6.0 and that of northern Tiaushan is only around Ms5.0 - 6.0. 展开更多
关键词 TIANSHAN Stage of the seismic energy accumulation Seismic activity
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Buoyance-driven hydrocarbon accumulation depth and its implication for unconventional resource prediction 被引量:25
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作者 Xiongqi Pang Chengzao Jia +6 位作者 Wenyang Wang Zhangxin Chen Maowen Li Fujie Jiang Tao Hu Ke Wang Yingxun Wang 《Geoscience Frontiers》 SCIE CAS CSCD 2021年第4期93-109,共17页
The discovery of unconventional hydrocarbon resources since the late 20th century changed geologists’understanding of hydrocarbon migration and accumulations and provides a solution to energy shortage.In 2016,unconve... The discovery of unconventional hydrocarbon resources since the late 20th century changed geologists’understanding of hydrocarbon migration and accumulations and provides a solution to energy shortage.In 2016,unconventional oil production in the USA accounted for 41%of the total oil production;and unconventional natural gas production in China accounted for 35%of total gas production,showing strong growth momentum of unconventional hydrocarbons explorations.Unconventional hydrocarbons generally coexist with conventional petroleum resources;they sometimes distribute in a separate system,not coexisting with a conventional system.Identification and prediction of unconventional resources and their potentials are prominent challenges for geologists.This study analyzed the results of 12,237 drilling wells in six representative petroliferous basins in China and studied the correlations and differences between conventional and unconventional hydrocarbons by comparing their geological features.Migration and accumulation of conventional hydrocarbon are caused dominantly by buoyance.Wepropose a concept of buoyance-driven hydrocarbon accumulation depth to describe the deepest hydrocarbon accumulation depth driven dominantly by buoyance;beyond this depth the buoyance becomes unimportant for hydrocarbon accumulation.We found that the buoyance-driven hydrocarbon accumulation depth in petroliferous basins controls the different oil/gas reservoirs distribution and resource potentials.Hydrocarbon migration and accumulations above this depth is dominated by buoyancy,forming conventional reservoirs in traps with high porosity and permeability,while hydrocarbon migration and accumulation below this depth is dominated by non-buoyancy forces(mainly refers to capillary force,hydrocarbon volumeexpansion force,etc.),forming unconventional reservoirs in tight layers.The buoyance-driven hydrocarbon accumulation depths in six basins in China range from 1200mto 4200 m,which become shallowerwith increasing geothermal gradient,decreasing particle size of sandstone reservoir layers,or an uplift in the whole petroliferous basin.The predicted unconventional resource potential belowthe buoyance-driven hydrocarbon accumulation depth in six basins in China is more than 15.71×10^(9) t oil equivalent,among them 4.71×10^(9) t reserves have been proved.Worldwide,94%of 52,926 oil and gas reservoirs in 1186 basins are conventional reservoirs and only 6%of them are unconventional reservoirs.These 94%conventional reservoirs show promising exploration prospects in the deep area below buoyance-driven hydrocarbon accumulation depth. 展开更多
关键词 Nature energy Fossil energy Oil and gas resources Conventional hydrocarbon reservoirs Unconventional hydrocarbon reservoirs Buoyance-driven hydrocarbon accumulation DEPTH
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In situ studies of energy-related electrochemical reactions using Raman and X-ray absorption spectroscopy 被引量:6
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作者 Heng‐Quan Chen Lie Zou +4 位作者 Di‐Ye Wei Ling‐Ling Zheng Yuan‐Fei Wu Hua Zhang Jian‐Feng Li 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第1期33-46,共14页
Electrochemical energy conversion technologies involving processes such as water splitting and O_(2)/CO_(2) reduction,provide promising solutions for addressing global energy scarcity and minimizing adverse environmen... Electrochemical energy conversion technologies involving processes such as water splitting and O_(2)/CO_(2) reduction,provide promising solutions for addressing global energy scarcity and minimizing adverse environmental impact.However,due to a lack of an in-depth understanding of the reaction mechanisms and the nature of the active sites,further advancement of these techniques has been limited by the development of efficient and robust catalysts.Therefore,in situ characterization of these electrocatalytic processes under working conditions is essential.In this review,recent applications of in situ Raman spectroscopy and X-ray absorption spectroscopy for various nano-and single-atom catalysts in energy-related reactions are summarized.Notable cases are highlighted,including the capture of oxygen-containing intermediate species formed during the reduction of oxygen and oxidation of hydrogen,and the detection of catalyst structural transformations occurring with the change in potential during the evolution of oxygen and reduction of CO_(2).Finally,the challenges and outlook for advancing in situ spectroscopic technologies to gain a deeper fundamental understanding of these energy-related electrocatalytic processes are discussed. 展开更多
关键词 Raman spectroscopy x-ray absorption spectroscopy In situ characterization ELECTROCATALYSIS energy conversion and storage
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Monte Carlo simulation for bremsstrahlung and photoneutron yields in high-energy x-ray radiography 被引量:1
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作者 许海波 彭现科 陈朝斌 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第6期213-220,共8页
This paper reports on the results of calculations using a Monte Carlo code (MCNP5) to study the properties of photons, electrons and photoneutrons obtained in the converted target and their transportations in x-ray ... This paper reports on the results of calculations using a Monte Carlo code (MCNP5) to study the properties of photons, electrons and photoneutrons obtained in the converted target and their transportations in x-ray radiography. A comparison between measurements and calculations for bremsstrahlung and photoneutrons is presented. The radiographic rule and the effect of the collimator on the image are studied with the experimental model. The results provide exact parameters for the optimal design of radiographic layout and shielding systems. 展开更多
关键词 x-ray radiography BREMSSTRAHLUNG PHOTONEUTRON energy spectrum angular distribution
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Theoretical study on K,L,and M X-ray transition energies and rates of neptunium and its ions 被引量:1
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作者 Ismail Abdalla Saber 董晨钟 +2 位作者 王向丽 周卫东 武中文 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第2期193-198,共6页
The transition energies and electric dipole (El) transition rates of the K, L, and M lines in neutral Np have been theoretically determined from the MultiConfiguration Dirac-Fock (MCDF) method. In the calculations... The transition energies and electric dipole (El) transition rates of the K, L, and M lines in neutral Np have been theoretically determined from the MultiConfiguration Dirac-Fock (MCDF) method. In the calculations, the contributions from Breit interaction and quantum electrodynamics (QED) effects (vacuum polarization and self-energy), as well as nu- clear finite mass and volume effects, are taken into account. The calculated transition energies and rates are found to be in good agreement with other experimental and theoretical results. The accuracy of the results is estimated and discussed. Furthermore, we calculated the transition energies of the same lines radiating from the decaying transitions of the K-, L-, and M-shell hole states of Np ions with the charge states Np1+ to Np6+ for the first time. We found that for a specific line, the corresponding transition energies relating to all the Np ions are almost the same; it means the outermost electrons have a very small influence on the inner-shell transition processes. 展开更多
关键词 Np ions K L and M x-rays transition energies transition rates
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Determination of Element Levels of Lagoon from Townships near Cocody City Abidjan Côte D’Ivoire Using Energy Dispersive X-Ray Fluorescence 被引量:1
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作者 Alfred Djoman Djama Agbo Koudou Djagouri +1 位作者 Jean-Claude Olkalé Brigui Konin Pierre-Claver Kakou 《World Journal of Nuclear Science and Technology》 2021年第2期109-118,共10页
Eight water bottles from Ebrie lagoon with pollution potency were studied using nuclear chemistry technique and Energy dispersive X-ray fluorescence. This pollution is characterized by pH and conductivity parameters, ... Eight water bottles from Ebrie lagoon with pollution potency were studied using nuclear chemistry technique and Energy dispersive X-ray fluorescence. This pollution is characterized by pH and conductivity parameters, concentrations average in mg/L of metals such Fe (0.731), Mn (0.345), Cr (0.070), Cu (0.014) and concentrations of nutrients known to be pollutants and toxic for living or-ganisms. These heavy metals are dangerous to the lives, the local inhabitants and also a threat to aquatic life since this water is essential for the economical town, Abidjan. According to the Manganese concentration average (0.345 mg) values that higher than WHO (0.05 mg) value, the main likely source of pollu-tants is anthropogenic, industrial and agricultural. This study also shows the use of materials and lubricants near the lagoon that pollute this water. 展开更多
关键词 Ebrie Lagoon POLLUTION Heavy Metals energy Dispersive x-ray Fluorescence
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Evaluation of the Performance of Lithium-Ion Accumulators for Photovoltaic Energy Storage
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作者 Toussaint Tilado Guingane Dominique Bonkoungou +4 位作者 Eric Korsaga Dieudonné Simpore Soumaila Ouedraogo Zacharie Koalaga François Zougmore 《Energy and Power Engineering》 2023年第12期517-526,共10页
In a context of climate change exacerbated by the increasing scarcity of fossil fuels, renewable energies, in particular photovoltaic solar energy, offer a promising alternative. Solar energy is non-polluting, globall... In a context of climate change exacerbated by the increasing scarcity of fossil fuels, renewable energies, in particular photovoltaic solar energy, offer a promising alternative. Solar energy is non-polluting, globally available and the most widely distributed resource on Earth. However, the intermittency of this energy source considerably limits its expansion. To solve this problem, storage techniques are being used, in particular, electrochemical storage using lithium-ion batteries. In this article, we will evaluate the performance of lithium-ion batteries when integrated into a photovoltaic grid. To do this, modelling and simulation of a photovoltaic system connected to a lithium-ion battery storage system will be carried out using MATLAB/Simulink software. A diagnostic of the energy consumption of the Kaya Polytechnic University Centre will be carried out, and the data will then be used in the simulator to observe the behaviour of the PV-Lion system. The results obtained indicate that lithium-ion batteries can effectively meet the centre’s energy demand. In addition, it was observed that lithium-ion batteries perform better under high energy demand than the other battery technologies studied. Successive storage systems with the same capacity but different battery technologies were compared. It was found that these storage systems can handle a maximum power of 4 × 10<sup>5</sup> W for lead-acid batteries, 6.5 × 10<sup>5</sup> W for nickel-cadmium batteries, 8.5 × 10<sup>5</sup> W for nickel-metal-hydride batteries, and more than 10 × 10<sup>5</sup> W for lithium-ion technology. 展开更多
关键词 Photovoltaic energy energy Storage Lithium-Ion accumulator MODELING MATLAB/Simulink Simulation
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Alpha-actinin expression at different differentiating time points from temporal lobe cerebral cortex neural stem cells to neuron-like cells using energy dispersive X-ray analysis
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作者 Bo Yu Hua Li +3 位作者 Zhe Du Yang Hong Meng Sang Yuxiu Shi 《Neural Regeneration Research》 SCIE CAS CSCD 2009年第4期265-270,共6页
BACKGROUND: Alpha-actinin ( a -actinin) plays a key role in neuronal growth cone migration during directional differentiation from neural stem cells (NSCs) to neurons. OBJECTIVE: To detect in situ microdistribut... BACKGROUND: Alpha-actinin ( a -actinin) plays a key role in neuronal growth cone migration during directional differentiation from neural stem cells (NSCs) to neurons. OBJECTIVE: To detect in situ microdistribution and quantitative expression of a -actinin during directional differentiation of NSCs to neurons in the temporal lobe cerebral cortex of neonatal rats. DESIGN, TIME AND SETTING: Between January 2006 and December 2008, culture and directional differentiation of NSCs were performed at Department of Histology and Embryology, Preclinical Medical College, China Medical University. Immune electron microscopy was performed at Department of Histology and Embryology and Department of Electron Micrology, Preclinical Medical College, China Medical University. Spectrum analysis was performed at Laboratory of Electron Microscopy, Mental Research Institute, Chinese Academy of Sciences. MATERIALS: Basic fibroblast growth factor, epidermal growth factor, brain-derived nerve growth factor, type-1 insulin like growth factor, and a -actinin antibody were provided by Gibco BRL, USA; rabbit-anti-rat nestin monoclonal antibody, rabbit-anti-rat neuron specific enolase polyclonal antibody, and EDAX-9100 energy dispersive X-ray analysis were provided by PHILIPS Company, Netherlands. METHODS: NSCs, following primary and passage culture, were differentiated with serum culture medium (DMEM/F12 + 10% fetal bovine serum + 2 ng/mL brain-derived nerve growth factor + 2 ng/mL type-1 insulin like growth factor). MAIN OUTCOME MEASURES: Expression of a -actinin in neuron-like cells was quantitatively and qualitatively detected with immunocytochemistry using energy dispersive X-ray analysis. RESULTS: Immunocytochemistry, combined with electron microscopy, indicated that positive α -actinin expression was like a spheroid particle with high electron density. In addition, the expression was gradually concentrated from the nuclear edge to the cytoplasm and expanded into developing neurites, during differentiation of neural stem cells to neurons. Conversely, energy dispersive X-ray analysis indicated that the more mature the neural differentiation was, and the greater the expression of α -actinin. CONCLUSION: The gradual increase of α -actinin expression is related to growth, development, and maturity of differentiated neuron-like cells, in neonatal rat frontal lobe cortex, at different differentiating time points of NSCs to neurons. 展开更多
关键词 energy dispersive x-ray analysis a -actinin neural stem cells directional differentiation NEURONS
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Studies of K-shell x-ray energy shifts induced by MeV/u heavy ions
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作者 宋张勇 杨治虎 +8 位作者 邵剑雄 崔莹 张红强 阮芳芳 杜鹃 高志民 于得洋 陈熙萌 蔡晓红 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第4期1443-1450,共8页
This paper reports that the K x-ray spectra of the thin target 4TAg, 4sCd, 49In and 50Sn were measured by an HPGe semi-conductor detector in collisions with 84.5 MeV 6C4+ ions. Our experiment revealed the Kα x-ray e... This paper reports that the K x-ray spectra of the thin target 4TAg, 4sCd, 49In and 50Sn were measured by an HPGe semi-conductor detector in collisions with 84.5 MeV 6C4+ ions. Our experiment revealed the Kα x-ray energy shifts were not obvious and the Kβ1 x-ray energy shifts were about 90-110 eV. The simple model of Burch et al has been previously used to calculate the K x-ray energy shifts due to an additional vacancy in 2p orbit. The present work extends the model of Burch to calculate the x-ray energy shifts of multiple ionized atoms induced by heavy ions with kinetic energy of MeV/u. In addition to our experimental results, many other experimental results are compared with the calculated values by using the model. 展开更多
关键词 K-shell x-ray energy shifts heavy ion collisions multiple ionization
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Energy-dispersive X-ray Spectroscopy for the Quantitative Analysis of Pyrite Thin Specimens
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作者 LUO Tingting GUO Yi +4 位作者 DENG Zhao LIU Xiaoqing SUN Zhenya QI Yanyuan YANG Meijun 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2023年第6期1304-1310,共7页
To explore ways to improve the accuracy of quantitative analysis of samples in the micrometer to nanometer range of magnitudes,we adopted analytical transmission electron microscopy(AEM/EDS)for qualitative and quantit... To explore ways to improve the accuracy of quantitative analysis of samples in the micrometer to nanometer range of magnitudes,we adopted analytical transmission electron microscopy(AEM/EDS)for qualitative and quantitative analysis of pyrite materials.Additionally,the k factor of pyrite is calculated experimentally.To develop an appropriate non-standard quantitative analysis model for pyrite materials,the experimentally calculated k factor is compared with that estimated from the non-standard quantitative analytical model of the instrument software.The experimental findings demonstrate that the EDS attached to a TEM can be employed for precise quantitative analysis of micro-and nanoscale regions of pyrite materials.Furthermore,it serves as a reference for improving the results of the EDS quantitative analysis of other sulfides. 展开更多
关键词 analytical transmission electron microscopy(AEM) energy dispersive x-ray spectroscopy(EDS) PYRITE thin specimen quantitative analysis
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A Hybrid Angular/Energy Dispersive Method to Improve Some Characteristics of Laboratory X-Ray Diffraction
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作者 V. Rossi Albertini D. Bailo +1 位作者 A. Generosi B. Paci 《Modern Instrumentation》 2012年第1期1-7,共7页
The Energy Dispersive X-ray Diffraction, generally referred as EDXD, has shown to be a valid alternative to the conventional Angular Dispersive X-ray Diffraction, the ADXD. EDXD exhibits several advantages to its AD c... The Energy Dispersive X-ray Diffraction, generally referred as EDXD, has shown to be a valid alternative to the conventional Angular Dispersive X-ray Diffraction, the ADXD. EDXD exhibits several advantages to its AD counterpart, mainly related to the properties of the polychromatic X-ray beam utilized for diffracting, such as higher signal intensities, a wider accessible region of the reciprocal space, a greater transparency of samples, and a parallel data collection of the q-points in the diffraction pattern acquisition. However, the main drawback of poly-chromaticity lays in the fact that the quantities that modulate the scattered intensity in a diffraction measurement depend on the energy. These quantities are the primary X-ray beam spectrum, polarization, and X-ray absorption, the last producing by far the most critical effect because it rapidly changes as a function of energy. Therefore, a detailed knowledge of the energy dependence of all these quantities is required in EDXD in order to process the data correctly and prevent systematic errors. The difficulty in handling the energy-dependent factors complicates the experimental procedure and may make the measurements unreliable. In the present paper, a hybrid method between the ED and AD X-ray Diffraction is proposed to maintain the advantages of the polychromatic nature of the radiation utilized in EDXD, while preventing the problems produced by the energy-dependent quantities. 展开更多
关键词 x-ray DIFFRACTION energy DISPERSIVE ANGULAR DISPERSIVE
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The Total Energy in the Interaction of X-Ray Photons with Capacitors
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作者 S. I. Hassan G. Scarel 《World Journal of Condensed Matter Physics》 2020年第4期159-177,共19页
<strong>Context and Background</strong>: In this research, we investigate the interaction of X-rays with a capacitor by studying the voltage established in the capacitor during the illumination. <strong... <strong>Context and Background</strong>: In this research, we investigate the interaction of X-rays with a capacitor by studying the voltage established in the capacitor during the illumination. <strong>Motivation</strong>: We aim at verifying that the total energy conserved in the interaction is <span style="white-space:nowrap;"><i></i></span><i>Pτ, i.e.<span style="white-space:nowrap;"></span></i> the product of the average power <span style="white-space:nowrap;"><i></i></span><i>P<span style="white-space:nowrap;"></span></i> times the period τ of the X-rays. <strong>Hypothesis</strong>: Our investigation relies on the hypothesis that the voltage responsivity π<span style="white-space:nowrap;"><i></i></span><i><sub>V<span style="white-space:nowrap;"></span></sub></i> of the capacitor should be small, according to previous research. The parameter π<span style="white-space:nowrap;"><i></i></span><i><sub>V<span style="white-space:nowrap;"></span></sub></i> is the ratio between the voltage produced and the average power <span style="white-space:nowrap;"><i></i></span><i>P<span style="white-space:nowrap;"></span></i> of the X-rays, and measures the performance of the capacitor in response to the X-rays. <strong>Method</strong>: We measure the voltage produced by the capacitor in response to the X-rays, and then determine the average power <span style="white-space:nowrap;"><i></i></span><i>P<span style="white-space:nowrap;"></span></i> of the X-rays according to a procedure already assessed with infrared and visible light. <strong>Results</strong>: In our experiments, <span style="white-space:nowrap;"><i></i></span><i>P<span style="white-space:nowrap;"></span></i> turns out to be in the range between 10<sup><span style="color:#4F4F4F;font-family:-apple-system, " font-size:16px;white-space:normal;background-color:#ffffff;"="">-</span>3 </sup>W to 10<sup>0</sup> W. Our procedure enables us to unveil the relationship between the average power P and the effective dose, an important operating parameter used to measure the delivery of X-rays in practical applications, such as standard X-ray medical imaging machines. <strong>Conclusions</strong>: We believe that our procedure paves the way for designing a possible X-ray power-meter, a tool presently missing in the market of X-ray characterization tools. 展开更多
关键词 x-rays POWER Light-Matter Interaction Conservation of energy
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Energy Dispersive X-Ray Spectroscopy of the Sohnari Member of Laki Formation from Southern Indus Basin of Pakistan
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作者 Muhammad Asif Noonari Surih Sibaghatullah Jagirani +5 位作者 Huafeng Tang Asghar A. A. D. Hakro Ali Ghulam Sahito Kaleemullah Jagirani Shahid Ali Shaikh Muhammad Dodo Jagirani 《Open Journal of Geology》 2021年第6期183-196,共14页
This study determines the geochemical and depositional environment analysis of the sediments of the Sohnari Member of the Laki Formation, Northern Kirthar Fold Belt of Pakistan. The Energy-Dispersive-X-Ray Spectroscop... This study determines the geochemical and depositional environment analysis of the sediments of the Sohnari Member of the Laki Formation, Northern Kirthar Fold Belt of Pakistan. The Energy-Dispersive-X-Ray Spectroscopy (EDS) technique is used for the detection of major elements and the effects of shifting depositional climatic conditions of six representative samples which were acquired from the Sohnari Member of the Laki Formation at Lakhra area, Sindh, Pakistan. The sedimentological studies clarify that the sediments the Sonahri Member are relatively immature and most migrated in clastic mode. The availability of Silica shows that the Member was formed due to biochemical precipitation and detrital mode and was deposited at a fast rate of sediment deposition under the fluvio-deltaic depositional system. This is also deduced that the rapid rate of sediment deposition might be created a reducing atmosphere and allowing for the mineralization of sulphur. 展开更多
关键词 energy Dispersive x-ray Spectroscopy GEOCHEMISTRY Sohnari Member the Laki Formation Northern Kirthar Fold Belt of Pakistan
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Application of Dual-Energy X-Ray Image Detection of Dangerous Goods Based on YOLOv7
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作者 Baosheng Liu Fei Wang +1 位作者 Ming Gao Lei Zhao 《Journal of Computer and Communications》 2023年第7期208-225,共18页
X-ray security equipment is currently a more commonly used dangerous goods detection tool, due to the increasing security work tasks, the use of target detection technology to assist security personnel to carry out wo... X-ray security equipment is currently a more commonly used dangerous goods detection tool, due to the increasing security work tasks, the use of target detection technology to assist security personnel to carry out work has become an inevitable trend. With the development of deep learning, object detection technology is becoming more and more mature, and object detection framework based on convolutional neural networks has been widely used in industrial, medical and military fields. In order to improve the efficiency of security staff, reduce the risk of dangerous goods missed detection. Based on the data collected in X-ray security equipment, this paper uses a method of inserting dangerous goods into an empty package to balance all kinds of dangerous goods data and expand the data set. The high-low energy images are combined using the high-low energy feature fusion method. Finally, the dangerous goods target detection technology based on the YOLOv7 model is used for model training. After the introduction of the above method, the detection accuracy is improved by 6% compared with the direct use of the original data set for detection, and the speed is 93FPS, which can meet the requirements of the online security system, greatly improve the work efficiency of security personnel, and eliminate the security risks caused by missed detection. 展开更多
关键词 x-ray Dangerous Goods Detection High and Low energy Image Fusion ACCURACY Real-Time Detection
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Ultrahard X-ray multifunctional application beamline at the SSRF
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作者 Ke Yang Zhao-Hui Dong +4 位作者 Chun-Yin Zhou Zi-Long Zhao Dong-Xu Liang Sai-Chao Cao Ai-Guo Li 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第6期14-25,共12页
The ultrahard X-ray multifunctional application beamline(BL12SW)is a phase-II beamline project at the Shanghai Syn-chrotron Radiation Facility.The primary X-ray techniques used at the beamline are high-energy X-ray di... The ultrahard X-ray multifunctional application beamline(BL12SW)is a phase-II beamline project at the Shanghai Syn-chrotron Radiation Facility.The primary X-ray techniques used at the beamline are high-energy X-ray diffraction and imaging using white and monochromatic light.The main scientific objectives of ultrahard X-ray beamlines are focused on two research areas.One is the study of the structural properties of Earth’s interior and new materials under extreme high-temperature and high-pressure conditions,and the other is the characterization of materials and processes in near-real service environments.The beamline utilizes a superconducting wiggler as the light source,with two diamond windows and SiC discs to filter out low-energy light(primarily below 30 keV)and a Cu filter assembly to control the thermal load entering the subsequent optical components.The beamline is equipped with dual monochromators.The first was a meridional bending Laue monochromator cooled by liquid nitrogen,achieving a full-energy coverage of 30-162 keV.The second was a sagittal bending Laue monochromator installed in an external building,providing a focused beam in the horizontal direction with an energy range of 60-120 keV.There were four experimental hutches:two large-volume press experimental hutches(LVP1 and LVP2)and two engineering material experimental hutches(ENG1 and ENG2).Each hutch was equipped with various near-real service conditions to satisfy different requirements.For example,LVP1 and LVP2 were equipped with a 200-ton DDIA press and a 2000-ton dual-mode(DDIA and Kawai)press,respectively.ENG1 and ENG2 provide in situ tensile,creep,and fatigue tests as well as high-temperature conditions.Since June 2023,the BL12SW has been in trial operation.It is expected to officially open to users by early 2024. 展开更多
关键词 Shanghai Synchrotron Radiation Facility Ultrahard x-ray High energy diffraction High energy imaging Engineering materials Earth science
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Two-dimensional particle-in-cell modeling of blow-off impulse by X-ray irradiation
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作者 Ruibo Li Jin-Long Jiao +3 位作者 Hui Luo Dezhi Zhang Dengwang Wang Kai Wang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第3期53-69,共17页
Space objects such as spacecraft or missiles may be exposed to intense X-rays in outer space,leading to severe damage.The reinforcement of these objects to reduce the damage caused by X-ray irradiation is a significan... Space objects such as spacecraft or missiles may be exposed to intense X-rays in outer space,leading to severe damage.The reinforcement of these objects to reduce the damage caused by X-ray irradiation is a significant concern.The blow-off impulse(BOI)is a crucial physical quantity for investigating material damage induced by X-ray irradiation.However,the accurate calculation of BOI is challenging,particularly for large deformations of materials with complex configurations.In this study,we develop a novel two-dimensional particle-in-cell code,Xablation2D,to calculate BOIs under far-field X-ray irradiation.This significantly reduces the dependence of the numerical simulation on the grid shape.The reliability of this code is verified by simulation results from open-source codes,and the calculated BOIs are consistent with the experimental and analytical results. 展开更多
关键词 x-ray irradiation energy deposition Blow-off impulse Particle in cells
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