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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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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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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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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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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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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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Effect of wire-arc directed energy deposition on the microstructural formation and age-hardening response of the Mg-9Al-1Zn(AZ91)alloy
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作者 Gloria Graf Petra Spoerk-Erdely +4 位作者 Emad Maawad Michael Burtscher Daniel Kiener Helmut Clemens Thomas Klein 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2023年第6期1944-1958,共15页
In recent years,wire-arc directed energy deposition(wa DED),which is also commonly known as wire-arc additive manufacturing(WAAM),has emerged as a promising new fabrication technique for magnesium alloys.The major rea... In recent years,wire-arc directed energy deposition(wa DED),which is also commonly known as wire-arc additive manufacturing(WAAM),has emerged as a promising new fabrication technique for magnesium alloys.The major reason for this is the possibility of producing parts with a complex geometry as well as a fine-grained microstructure.While the process has been shown to be applicable for Mg-Al-Zn alloys,there is still a lack of knowledge in terms of the influence of the WAAM process on the age-hardening response.Consequently,this study deals with the aging response of a WAAM AZ91 alloy.In order to fully understand the mechanisms during aging,first,the as-built condition was analyzed by means of high-energy X-ray diffraction(HEXRD)and scanning electron microscopy.These investigations revealed a finegrained,equiaxed microstructure with adjacent areas of alternating Al content.Subsequently,the difference between single-and double-step aging as well as conventional and direct aging was studied on the as-built WAAM AZ91 alloy for the first time.The aging response during the various heat treatments was monitored via in situ HEXRD experiments.Corroborating electron microscopy and hardness studies were conducted.The results showed that the application of a double-step aging heat treatment at 325℃with pre-aging at 250℃slightly improves the mechanical properties when compared to the single-step heat treatment at 325℃.However,the hardness decreases considerably after the pre-aging step.Thus,aging at lower temperatures is preferable within the investigated temperature range of 250-325℃.Moreover,no significant difference between the conventionally aged and directly aged samples was found.Lastly,the specimens showed enhanced precipitation kinetics during aging as compared to cast samples.This could be attributed to a higher amount of nucleation sites and the particular temperature profile of the solution heat treatment. 展开更多
关键词 Wire-arc directed energy deposition Additive manufacturing High-energy x-ray diffraction Synchrotron Mg-Al-Zn alloys AGE-HARDENING
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XPS Studies on Electroless As-Deposited and Annealed Ni-P Films
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作者 Towhid Adnan Chowdhury 《Engineering(科研)》 2024年第5期123-133,共11页
Electroless deposition has been used to deposit Ni-P films on glass slides using the reducing agent sodium hypophosphite. This has been done with a purpose to use Ni-P films as back contact for silicon carbide radiati... Electroless deposition has been used to deposit Ni-P films on glass slides using the reducing agent sodium hypophosphite. This has been done with a purpose to use Ni-P films as back contact for silicon carbide radiation detectors. By keeping deposition time, temperature, pH and concentration of the precursor solution constant, the film deposition has been done. XPS studies were done to analyze the composition and stoichiometry of Ni-P thin films. 展开更多
关键词 NI-P x-ray Photoelectron Spectroscopy ANNEALING Electroless Deposition Binding energy Reducing Agent
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The development,performances and applications of the monochromatic X-rays facilities in(0.218–301)keV at NIM,China 被引量:4
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作者 Si-Ming Guo Jin-Jie Wu Dong-Jie Hou 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2021年第6期108-121,共14页
Space scientific exploration is rapidly becoming the primary battlefield for humankind to explore the universe.Countries worldwide have launched numerous space exploration satellites.Accurate calibration of the detect... Space scientific exploration is rapidly becoming the primary battlefield for humankind to explore the universe.Countries worldwide have launched numerous space exploration satellites.Accurate calibration of the detectors on the ground is a crucial element for space science satellites to obtain observational results.For the purpose of providing calibration for various satellite-borne detectors,multiple monochromatic X-rays facilities have been built at the National Institute of Metrology,P.R.China(NIM).These facilities mainly pertain to grating diffraction and Bragg diffraction,and the energy range of the produced monochromatic X-rays is 0.218–301 ke V.These facilities have a high performance in terms of energy stability,monochromaticity,and flux stability.The monochromaticity was greater than 3.0%.The energy stability of the facility is 0.02%at 25 ke V over 8 h,and the flux stability was within 1.0%at 25 ke V over 8 h.Calibration experiments on the properties of satellite-borne detectors,such as energy linearity,energy resolution,detection efficiency,and temperature response,can be conducted at the facilities.Thus far,the calibration of two satellites has been completed by the authors,and the work on three other satellites is in progress.This study will contribute to the advancement of X-ray astronomy the development of Chinese space science. 展开更多
关键词 Monochromatic x-rays MONOCHROMATOR Bragg diffraction energy spectra Calibration
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Readout electronics for a high-resolution soft X-ray spectrometer based on silicon drift detector 被引量:3
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作者 Er-Lei Chen Chang-Qing Feng +4 位作者 Shu-Bin Liu Chun-Feng Ye Dong-Dong Jin Jian Lian Hui-Jun Hu 《Nuclear Science and Techniques》 SCIE CAS CSCD 2017年第1期94-99,共6页
The readout electronics for a prototype soft X-ray spectrometer based on silicon drift detector(SDD),for precisely measuring the energy and arrival time of X-ray photons is presented in this paper.The system mainly co... The readout electronics for a prototype soft X-ray spectrometer based on silicon drift detector(SDD),for precisely measuring the energy and arrival time of X-ray photons is presented in this paper.The system mainly consists of two parts,i.e.,an analog electronics section(including a pre-amplifier,a signal shaper and filter,a constant fraction timing circuit,and a peak hold circuit)and a digital electronics section(including an ADC and a TDC).Test results with X-ray sources show that an energy dynamic range of 1-10 keV with an integral nonlinearity of less than 0.1%can be achieved,and the energy resolution is better than 160 eV @ 5.9 keV FWHM.Using a waveform generator,test results also indicate that time resolution of the electronics system is about 3.7 ns,which is much less than the transit time spread of SDD(<100 ns)and satisfies the requirements of future applications. 展开更多
关键词 energy and time measurement SOFT x-ray detection Silicon DRIFT DETECTOR READOUT ELECTRONICS
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Photon-in/photon-out endstation for studies of energy materials at beamline 02B02 of Shanghai Synchrotron Radiation Facility 被引量:2
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作者 任国玺 张念 +6 位作者 冯雪飞 章辉 于鹏飞 郑顺 周櫈 田宗旺 刘啸嵩 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第1期62-69,共8页
A new photon-in/photon-out endstation at beamline 02B02 of the Shanghai Synchrotron Radiation Facility for studying the electronic structure of energy materials has been constructed and fully opened to users.The endst... A new photon-in/photon-out endstation at beamline 02B02 of the Shanghai Synchrotron Radiation Facility for studying the electronic structure of energy materials has been constructed and fully opened to users.The endstation has the capability to perform soft x-ray absorption spectroscopy in total electron yield and total fluorescence yield modes simultaneously.The photon energy ranges from 40 eV to 2000 eV covering the K-edge of most low Z-elements and the L-edge of 3d transition-metals.The new self-designed channeltron detector allows us to achieve good fluorescence signals at the low photon flux.In addition,we synchronously collect the signals of a standard reference sample and a gold mesh on the upstream to calibrate the photon energy and monitor the beam fluctuation,respectively.In order to cross the pressure gap,in situ gas and liquid cells for soft x-ray absorption spectroscopy are developed to study the samples under realistic working conditions. 展开更多
关键词 soft x-ray absorption energy materials photon-in/photon-out in situ cell
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X-ray emission from 424-MeV/u C ions impacting on selected target 被引量:1
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作者 周贤明 程锐 +9 位作者 雷瑜 孙渊博 王瑜玉 王兴 徐戈 梅策香 张小安 陈熙萌 肖国青 赵永涛 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第2期143-147,共5页
The K-shell x-rays of Ti, V, Fe, Co, Ni, Cu, and Zn induced by 424-MeV/u C^(6+) ion impact are measured. It is found that the K x-ray shifts to the high energy side and the intensity ratio of Kβ/Kα is larger than... The K-shell x-rays of Ti, V, Fe, Co, Ni, Cu, and Zn induced by 424-MeV/u C^(6+) ion impact are measured. It is found that the K x-ray shifts to the high energy side and the intensity ratio of Kβ/Kα is larger than the atomic data, owing to the L-shell multiple-ionization. The x-ray production cross sections are deduced from the experimental counts and compared with the binary encounter approximation(BEA), plane wave approximation(PWBA) and energy-loss Coulomb-repulsion perturbed-stationary-state relativistic(ECPSSR) theoretical predictions. The BEA model with considering the multipleionization fluorescence yield is in better consistence with the experimental results. In addition, the cross section as a function of target atomic K-shell binding energy is presented. 展开更多
关键词 high energy heavy ions ion-atom collisions x-ray emission
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Quantum interference in laser-assisted photo-ionization excited by a femtosecond x-ray pulse
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作者 葛愉成 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第12期4492-4497,共6页
The photoelectron energy spectra (PESs) excited by monochromatic femtosecond x-ray pulses in the presence of a femtosecond laser are investigated. APES is composed of a set of separate peaks, showing interesting com... The photoelectron energy spectra (PESs) excited by monochromatic femtosecond x-ray pulses in the presence of a femtosecond laser are investigated. APES is composed of a set of separate peaks, showing interesting comb-like structures. These structures result from the quantum interferences between photoelectron wave packets generated at different times. The width and the localization of each peak as well as the number of peaks are determined by all the laser and x-ray parameters. Most of peak heights of the PES are higher than the classical predictions. 展开更多
关键词 femtosecond x-ray pulse PHOTO-IONIZATION quantum interference photoelectron energy spectrum
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Wood Moisture Content Measurement by X-Ray Exposure Method
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作者 尚德库 《Journal of Forestry Research》 SCIE CAS CSCD 1997年第1期54-58,共5页
Although quite a numer of papers can be found up to now dealing with the subject of the measurement ofwood density by using the X-ray exposure methods, direet scanning or radiographic photography, the following two as... Although quite a numer of papers can be found up to now dealing with the subject of the measurement ofwood density by using the X-ray exposure methods, direet scanning or radiographic photography, the following two aspects,which are very important from both theorctical and engineering application points of view, have not yet been properly handled. One is that the elementary analyses or the experimental measurement on the mass attenuation coefficients were notspecified in regard to spectnun energv distridutions [1]. In this connection, the ambiguities in the specification of the coeffiecients and in turn for thc results among studies arise when only one of the two parameters, namely wave length and applied voltage, of detining the energy spectrum of X-ray is given. The oher is that the relationships between the relative intensity and the sample thickness as well the wood moisture content [2], which are the critical factors for the design and theselection of X-ray apparatus, were not sufficiently examined. In addition, the knowledge of the measurelnent of woodmiosture content by using the direct X-ray scanning method is also almost unavaible now. In the study, the direct X-rayscanning method of measuring wood moisture content was at first investigated theoretically with respect to the relationshipbetween the mass attenuation coefficients of wood (beech, Fagus Sylvatica) and the maximum spectrum energy of X-ray.Secondly, the dependence of the relative intensity on the sample thickness and on the wood moisture content was analysed.The main advantage of the method is on-site nondestructive measuring of wood moisture content in the processes such asdrying, impregnation and unsteady mass diffusion. Specifically for the application in the area of biomechanics, the methodcan also bc used for understanding the water pathway within wood, for example, the water around the knots and the relation between the stress distribution and the local moisture content of wood. 展开更多
关键词 Mass attenuation coefficient Maximum spectrum energy Moisture content Relative intensity Sample thickness x-ray exposure
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