期刊文献+
共找到1,580篇文章
< 1 2 79 >
每页显示 20 50 100
Stony Brook’s High-Pressure Laboratory Collaborations with French Scientists 认领
1
作者 Robert Cooper Liebermann 《地球科学国际期刊(英文)》 2021年第3期195-212,共18页
For more than a half century, my colleagues and I in the Stony Brook High Pressure Laboratory have profited from collaborations with French scientists in their laboratories in Orsay, Paris, Toulouse, Lille, Lyon, Stra... For more than a half century, my colleagues and I in the Stony Brook High Pressure Laboratory have profited from collaborations with French scientists in their laboratories in Orsay, Paris, Toulouse, Lille, Lyon, Strasbourg and </span><span style="font-family:Verdana;">Rennes. These interactions have included postdoctoral appointments of French colleagues in our laboratory as well as two année sabbatique by me;in 1983-84</span><span style="font-family:Verdana;">, in the Laboratoire de Géophysique et Géodynamique Interne at the Université Paris XI in Orsay and in 2020-2003 in the Laboratoire des Méchanismes et Transfert en Géologie at the Université Paul Sabatier in Toulouse. The objective of this report is to relate this history and to illustrate the scientific advances which </span></span><span style="font-family:Verdana;">resulted</span><span style="font-family:Verdana;"> from these collaborations. 展开更多
关键词 Mineral Physics High Pressure High Temperature Multi-Anvil Apparatus Atomic Diffusion Mineral Deformation U.S.-France Collaboration Activation Volume for Creep Ultrasonic Interferometry Synchrotron X-Radiation
在线阅读 免费下载
Characterization of porous cobalt hexacyanoferrate and activated carbon electrodes under dynamic polarization conditions in a sodium-ion pseudocapacitor 认领
2
作者 Bruno Morandi Pires Willian Goncalves Nunes +5 位作者 Bruno Guilherme Freitas Francisca Elenice Rodrigues Oliveira Vera Katic Cristiane Barbieri Rodella Leonardo Morais Da Silva Hudson Zanin 《能源化学:英文版》 SCIE EI CAS CSCD 2021年第3期53-62,共10页
We report here the activated carbon and cobalt hexacyanoferrate composite,which is applied as the electrode materials in symmetric supercapacitors containing a 1.0 M Na2SO4 aqueous electrolyte.This novel materia... We report here the activated carbon and cobalt hexacyanoferrate composite,which is applied as the electrode materials in symmetric supercapacitors containing a 1.0 M Na2SO4 aqueous electrolyte.This novel material combines high specific surface area and electrochemical stability of activated carbon with the redox properties of cobalt hexacyanoferrate,resulting in maximum specific capacitance of 329 F g-1 with large voltage working window of 2.0 V.Electrochemical studies indicated that cobalt hexacyanoferrate introduces important pseudocapacitive properties accounting for the overall charge-storage process,especially when I<0.5 A g-1.At lower gravimetric currents(e.g.,0.05 A g-1)and up to 1.0 V,the presence of cobalt hexacyanoferrate improves the specific energy for more than 300%.In addition,to better understanding the energy storage process we also provided a careful investigation of the electrode materials under dynamic polarization conditions using the in situ Raman spectroscopy and synchrotron light Xray diffraction techniques.Interesting complementary findings were obtained in these studies.We believe that this novel electrode material is promising for applications regarding the energy-storage process in pseudocapacitors with long lifespan properties. 展开更多
关键词 Operando studies RAMAN XRD synchrotron light Cobalt hexacyanoferrate Activated carbon High specific capacitance
在线阅读 下载PDF
High-resolution ARPES endstation for in situ electronic structure investigations at SSRF 认领
3
作者 Yi-Chen Yang Zheng-Tai Liu +8 位作者 Ji-Shan Liu Zhong-Hao Liu Wan-Ling Liu Xiang-Le Lu Hong-Ping Mei Ang Li Mao Ye Shan Qiao Da-Wei Shen 《核技术:英文版》 SCIE EI CAS CSCD 2021年第3期94-106,共13页
Angle-resolved photoemission spectroscopy(ARPES)is one of the most powerful experimental techniques in condensed matter physics.Synchrotron ARPES,which uses photons with high flux and continuously tunable energy,has b... Angle-resolved photoemission spectroscopy(ARPES)is one of the most powerful experimental techniques in condensed matter physics.Synchrotron ARPES,which uses photons with high flux and continuously tunable energy,has become particularly important.However,an excellent synchrotron ARPES system must have features such as a small beam spot,super-high energy resolution,and a user-friendly operation interface.A synchrotron beamline and an endstation(BL03 U)were designed and constructed at the Shanghai Synchrotron Radiation Facility.The beam spot size at the sample position is 7.5(V)μm×67(H)μm,and the fundamental photon range is 7-165 eV;the ARPES system enables photoemission with an energy resolution of 2.67 meV at21.2 eV.In addition,the ARPES system of this endstation is equipped with a six-axis cryogenic sample manipulator(the lowest temperature is 7 K)and is integrated with an oxide molecular beam epitaxy system and a scanning tunneling microscope,which can provide an advanced platform for in situ characterization of the fine electronic structure of condensed matter. 展开更多
关键词 SYNCHROTRON ARPES In situ VUV laser Quantum materials
在线阅读 下载PDF
The synergy of modulated surface polarity and oxygen vacancy for CO2 to methanol over Zn(δ-)-Ti(δ+)Ovacancy 认领
4
作者 Junfu Zhou Lin Ye +4 位作者 Daofeng Huang Meiyin Wang Yuanhang Ren Bin Yue Heyong He 《能源化学:英文版》 SCIE EI CAS CSCD 2021年第5期449-454,共6页
Bi-functional catalysts,which can be traced back to 1960s,are widely applied in energy conversion and chemical transformation[1].Generally,the enhanced performance of the bi-functional catalyst comes from the local ge... Bi-functional catalysts,which can be traced back to 1960s,are widely applied in energy conversion and chemical transformation[1].Generally,the enhanced performance of the bi-functional catalyst comes from the local geometry or electron density change after the second component introduced.These changes facilitate the reaction at the structure or electron density level[2].In fact,it is a great challenge to understand and control those effects[3]. 展开更多
关键词 CO2conversion Zn species Oxygen vacancy SYNERGY Formate route Synchrotron XRD
在线阅读 下载PDF
The effect of nitrogen on the compressibility and conductivity of iron at high pressure 认领
5
作者 Yukai Zhuang Xiaowan Su +4 位作者 Nilesh P.Salke Zhongxun Cui Qingyang Hu Dongzhou Zhang Jin Liu 《地学前缘:英文版》 SCIE CAS CSCD 2021年第2期983-989,共7页
Although nitrogen in the Earth’s interior has attracted significant attention recently,it remains the most enigmatic of the light elements in the Earth’s core.In this work,synchrotron X-ray diffraction(XRD)and elect... Although nitrogen in the Earth’s interior has attracted significant attention recently,it remains the most enigmatic of the light elements in the Earth’s core.In this work,synchrotron X-ray diffraction(XRD)and electrical conductivity experiments were conducted on iron nitrides(Fe2N and Fe4N)in diamond anvil cells(DACs)up to about 70 GPa at ambient temperature.These results show that iron nitrides are stable up to at least 70 GPa.From the equation of state(EOS)parameters,iron nitrides are more compressible than iron carbides.Moreover,using the van der Pauw method and Wiedemann-Franz law,the electrical and thermal conductivity of samples were determined to be much lower than that of iron carbides.The conductivities of Fe2N and Fe4N were similar at 20–70 GPa,suggesting no evident effects by varying the N stoichiometries in iron nitrides.Iron nitrides are less dense and conductive but more compressible than carbides at 0–70 GPa.This study indicates that less nitrogen than carbon can explain geophysical phenomena in the deep Earth,such as the density deficit. 展开更多
关键词 High pressure Iron nitrides Synchrotron X-ray diffraction Electrical conductivity
在线阅读 下载PDF
Synchrotron radiation-based materials characterization techniques shed light on molten salt reactor alloys 认领 被引量:1
6
作者 Li Jiang Xiang-Xi Ye +1 位作者 De-Jun Wang Zhi-Jun Li 《核技术:英文版》 SCIE CAS CSCD 2020年第1期57-71,共15页
From a safety point of view, it is important to study the damages and reliability of molten salt reactor structural alloy materials, which are subjected to extreme environments due to neutron irradiation, molten salt ... From a safety point of view, it is important to study the damages and reliability of molten salt reactor structural alloy materials, which are subjected to extreme environments due to neutron irradiation, molten salt corrosion, fission product attacks, thermal stress, and even combinations of these. In the past few years, synchrotron radiation-based materials characterization techniques have proven to be effective in revealing the microstructural evolution and failure mechanisms of the alloys under surrogating operation conditions. Here, we review the recent progress in the investigations of molten salt corrosion,tellurium(Te) corrosion, and alloy design. The valence states and distribution of chromium(Cr) atoms, and the diffusion and local atomic structure of Te atoms near the surface of corroded alloys have been investigated using synchrotron radiation techniques, which considerably deepen the understandings on the molten salt and Te corrosion behaviors. Furthermore, the structure and size distribution of the second phases in the alloys have been obtained, which are helpful for the future development of new alloy materials. 展开更多
关键词 MOLTEN SALT reactor Alloy materials SYNCHROTRON RADIATION Shanghai SYNCHROTRON RADIATION Facility MOLTEN SALT CORROSION TELLURIUM CORROSION
在线阅读 下载PDF
Hot deformation of Mg-Y-Zn alloy with a low content of the LPSO phase studied by in-situ synchrotron radiation diffraction 认领
7
作者 Klaudia Horváth Fekete Daria Drozdenko +5 位作者 Jan Capek Kristián Máthis Domonkos Tolnai Andreas Stark Gerardo Garcés Patrik Dobron 《镁合金学报(英文)》 SCIE 2020年第1期199-209,共11页
The compressive deformation behavior of the extruded WZ42(Mg98.5Y1Zn0.5 in at.%)magnesium alloy containing a low amount of long-period stacking ordered(LPSO)phase was studied by in-situ synchrotron radiation diffracti... The compressive deformation behavior of the extruded WZ42(Mg98.5Y1Zn0.5 in at.%)magnesium alloy containing a low amount of long-period stacking ordered(LPSO)phase was studied by in-situ synchrotron radiation diffraction technique.Tests were conducted at temperatures between room temperature and 350℃.Detailed microstructure investigation was provided by scanning electron microscopy,particularly the backscattered electron imaging and electron backscatter diffraction technique.The results show that twinning lost its dominance and kinking of the LPSO phase became more pronounced with increasing deformation temperature.No cracks of the LPSO phase and no debonding r at the interface between the LPSO phase and the Mg matrix were observed at temperatures above 200℃.At 350℃,the LPSO phase lost its strengthening effect and the deformation of the alloy was mainly realized by the dynamic recrystallization of the Mg matrix. 展开更多
关键词 Magnesium alloy LPSO phase KINKING High temperature Synchrotron radiation diffraction
在线阅读 下载PDF
Understanding Structural Evolution in the Synthesis of Advanced Energy Materials 认领 被引量:1
8
作者 ZHANG Ming-Jian CHEN Yu-Sheng +1 位作者 PAN Feng REN Yang 《结构化学》 SCIE CAS CSCD 2020年第1期26-30,1共6页
Developing a variety of in situ characterization techniques to unravel the structural/chemical evolution during the synthesis of various advanced energy materials for studying the relationship among those experimental... Developing a variety of in situ characterization techniques to unravel the structural/chemical evolution during the synthesis of various advanced energy materials for studying the relationship among those experimental conditions and the structure is the key to implement the controllable synthesis of battery materials.This perspective summarizes the recent studies into structural evolution during in situ synthesis of various advanced energy materials by synchrotron X-ray diffraction technique and forecasts the more extensive applications in the future. 展开更多
关键词 structure evolution synthesis ADVANCED energy materials in SITU SYNCHROTRON X-RAY DIFFRACTION
Excellent reusability of FeBC amorphous ribbons induced by progressive formation of through-pore structure during acid orange 7 degradation 认领
9
作者 Fang Miao Qianqian Wang +4 位作者 Qiaoshi Zeng Long Hou Tao Liang Zhiqiang Cui Baolong Shen 《材料科学技术:英文版》 SCIE EI CAS CSCD 2020年第3期107-118,共12页
The high-efficient degrading ability of Fe BC amorphous ribbons toward acid orange 7(AO7)via redox reactions is reported and compared with that of Fe PC amorphous ribbons.The time required for degrading50%of AO7 using... The high-efficient degrading ability of Fe BC amorphous ribbons toward acid orange 7(AO7)via redox reactions is reported and compared with that of Fe PC amorphous ribbons.The time required for degrading50%of AO7 using Fe BC amorphous ribbons is only 1/3 of that using Fe PC amorphous ribbons.In the Fe BC amorphous matrix,galvanic cell structures are formed between the Fe-B and Fe-C bonds because of the large difference in their bonding strengths,which contributes to the low reaction activation energy and the high degrading efficiency of Fe BC amorphous ribbons.The extremely long service life of Fe BC amorphous ribbons comes from the progressive formation of 3 D porous nanosheet networks that allow more efficient mass transport and a larger specific surface area.The Fe BC amorphous ribbons show a satisfying degrading ability in not only acidic but also neutral and weak alkaline AO7 solutions.This work provides an effective and environmental-friendly material for degrading azo dyes. 展开更多
关键词 3D NANOSHEET arrays Through-pore Wastewater treatment FeBC amorphous alloys SYNCHROTRON XRD
Ore Forming Fluids of Several Gold Deposits in the Irtysh Gold Belt, Xinjiang, China 认领
10
作者 Yingwei Wang Jiuhua Xu +3 位作者 Rufu Ding Hui Zhang Xihui Cheng Chunjing Bian 《地球科学学刊:英文版》 SCIE CAS CSCD 2020年第2期298-312,共15页
The metallogenic environment of the Irtysh gold belt in Xinjiang is studied in detail.The metallogenic geological background,metallogenic conditions and ore-controlling factors of the gold deposits in eastern,central ... The metallogenic environment of the Irtysh gold belt in Xinjiang is studied in detail.The metallogenic geological background,metallogenic conditions and ore-controlling factors of the gold deposits in eastern,central and western regions of the metallogenic belt are compared.The metallogenic structure of the Irtysh tectonic belt has the characteristics of diverging to the west and converging to the east.Composite ore controlling by ductile shearing and magmatic activity in Irtysh gold belt result in zoned and segmented distribution of gold mineralization.Through the fluid inclusion research and H-O-S isotope analysis,the evolution regularity of gold ore-forming fluids in the region was analyzed.Synchrotron radiation X-ray fluorescence was used to analysis the concentration of metal elements in a single fluid inclusion,explaining the occurrence and migration process of Au in hydrothermal fluid.The source of ore forming minerals in western gold deposit is more closely related to magmatic activity,and the structural metamorphism of eastern gold deposit has greater influence on mineralization.Metallogenic fluids of gold deposits are characterized by metamorphic water(and magmatic water)in the early stage and mixed with meteoric water in the late stage.And the metallogenic elements are enriched in CO2 rich fluid.The Au is mainly activated,migrated and enriched with the mixed fluid of magmatic hydrothermal,metamorphic hydrothermal and atmospheric precipitation in the medium-low temperature,shallow to medium-deep environment. 展开更多
关键词 Irtysh gold belt ORE FORMING FLUIDS H-O-S isotope SYNCHROTRON radiation X-ray fluorescence METALLOGENIC model
Damage evolution of PμLSE additive-manufactured micro-lattice metastructures: Synchrotron radiation 3D tomography image-based analysis 认领
11
作者 QingLiang Zeng WenWang Wu +3 位作者 WenXia Hu Li Xi Ran Tao DaiNing Fang 《中国科学:物理学、力学、天文学英文版》 SCIE EI CAS CSCD 2020年第10期71-80,共10页
The manufacturing of additives with projection micro litho stereo exposure(PμLSE)has provided an opportunity for the fabrication of metastructures with complex microstructures at micro-nano resolutions.However,the pe... The manufacturing of additives with projection micro litho stereo exposure(PμLSE)has provided an opportunity for the fabrication of metastructures with complex microstructures at micro-nano resolutions.However,the performance evaluation of as-fabricated metastructures is challenging.The benefit of synchrotron radiation-based 3 D imaging techniques and advanced image processing methods makes it is feasible to study fabrication defects and damage processes of micro-nanoscale bodycentered cubic(BCC)lattices manufactured with PμLSE.First,synchrotron radiation technology is used to capture the structural features inside the micro-lattice samples.Subsequently,several types of statistical defects-based image finite element models are adopted to analyze the failure process of the structure under compression loading.Finally,comparisons between in situ experiments and numerical simulation results are performed for verification.The method of the combined non-destructive testing of synchrotron radiation and image finite element technology provides a robust technique for evaluating the performances of additive-manufactured micro-lattice with complex microstructures. 展开更多
关键词 synchrotron radiation X-ray micro-lattice image finite element method in situ compression experiment
Integration of machine learning with phase field method to model the electromigration induced Cu6Sn5 IMC growth at anode side Cu/Sn interface 认领
12
作者 Anil Kunwar Yuri Amorim Coutinho +2 位作者 Johan Hektor Haitao Ma Nele Moelans 《材料科学技术:英文版》 SCIE EI CAS CSCD 2020年第24期203-219,共17页
Currently,in the era of big data and 5G communication technology,electromigration has become a serious reliability issue for the miniaturized solder joints used in microelectronic devices.Since the effective charge nu... Currently,in the era of big data and 5G communication technology,electromigration has become a serious reliability issue for the miniaturized solder joints used in microelectronic devices.Since the effective charge number(Z*)is considered as the driving force for electromigration,the lack of accurate experimental values for Z* poses severe challenges for the simulation-aided design of electronic materials.In this work,a data-driven framework is developed to predict the Z* values of Cu and Sn species at the anode based LIQUID,Cu6Sn5 intermetallic compound(IMC)and FCC phases for the binary Cu-Sn system undergoing electromigration at 523.15 K.The growth rate constants(kem)of the anode IMC at several magnitudes of applied low current density(j=1×10^6 to 10×10^6A/m^2)are extracted from simulations based on a 1D multi-phase field model.A neural network employing Z* and j as input features,whereas utilizing these computed kemdata as the expected output is trained.The results of the neural network analysis are optimized with experimental growth rate constants to estimate the effective charge numbers.For a negligible increase in temperature at low j values,effective charge numbers of all phases are found to increase with current density and the increase is much more pronounced for the IMC phase.The predicted values of effective charge numbers Z* are then utilized in a 2D simulation to observe the anode IMC grain growth and electrical resistance changes in the multi-phase system.As the work consists of the aspects of experiments,theory,computation,and machine learning,it can be called the four paradigms approach for the study of electromigration in Pb-free solder.Such a combination of multiple paradigms of materials design can be problem-solving for any future research scenario that is marked by uncertainties regarding the determination of material properties. 展开更多
关键词 Phase field method Artificial neural network Intemetallic compound Current density Synchrotron radiation
Research progress on solidification structure of alloys by synchrotron X-ray radiography: A review 认领
13
作者 Yongbiao Wang Sensen Jia +3 位作者 Mingguang Wei Liming Peng Yujuan Wu Xintian Liu 《镁合金学报(英文)》 SCIE 2020年第2期396-413,共18页
The synchrotron radiation technology has recently emerged as a powerful tool to characterize the real-time microstructure evolution during solidification of alloys.Compared with other methods,the synchrotron radiation... The synchrotron radiation technology has recently emerged as a powerful tool to characterize the real-time microstructure evolution during solidification of alloys.Compared with other methods,the synchrotron radiation technology,along with its unique advantages of strong brightness,high energy,excellent resolution,and good monochromaticity,allows for capturing the dendrite evolution behavior of alloys in real time and can be dynamically coordinated with high-resolution CCD(Charge-coupled Device)imaging systems.This paper briefly reviews the recent advances in developing synchrotron radiation for solidification of alloys with low,medium,and high melting points,and under the external electric,magnetic,and ultrasonic fields.Furthermore,a series of microstructural features and behaviors such as dendrite morphology,growth orientation,dendrite fracture,and rotation are described in detail.Finally,the development trends and application prospects of synchrotron radiation technology in alloy solidification are forecasted. 展开更多
关键词 SOLIDIFICATION Synchrotron radiation Dendritic growth External field
在线阅读 下载PDF
Atomic scale structural analysis of liquid immiscibility in binary silicate melt:A case of SiO2–TiO2 system 认领
14
作者 Cuiyu Zhang Xuan Ge +5 位作者 Qiaodan Hu Fan Yang Pingsheng Lai Caijuan Shi Wenquan Lu Jianguo Li 《材料科学技术:英文版》 SCIE EI CAS CSCD 2020年第18期53-60,共8页
Thermodynamic/dynamic modeling of liquid immiscibility in silicates is seriously hindered due to lack of in situ investigation on the structural evolution of the melt.In this work,atomic-scale structural evolution of ... Thermodynamic/dynamic modeling of liquid immiscibility in silicates is seriously hindered due to lack of in situ investigation on the structural evolution of the melt.In this work,atomic-scale structural evolution of a classic binary silicate immiscible system,SiO2–TiO2,is tracked by in situ high energy X-ray diffraction(HE-XRD).It is found that both the configuration of[SiO]and the polymerization between them are closely coupled with embedment and extraction of the metallic cations(Ti^4+).[SiO]monomer goes through deficit-oxygen and excess-polymerization before liquid–liquid separation and enables self-healing after liquid–liquid separation,which challenges the traditional cognition that[SiO4]monomer is immutable.Ti4+cations with tetrahedral oxygen-coordination first participate in the network construction before liquid separation.The four-fold Ti–O bond is broken during liquid separation,which may facilitate the movement of Ti4+across the Si–O network to form TiO2-rich nodules.The structural features of nodules were also investigated and they were found highly analogous to that of molten TiO2,which implies a parallel crystallization behavior in the two circumstances.Our results shed light on the structural evolution scenario in liquid immiscibility at atomic scale,which will contribute to constructing a complete thermodynamic/dynamic framework describing the silicate liquid immiscibility systems beyond current models. 展开更多
关键词 Liquid immiscibility Atomic scale structure Synchrotron radiation In-situ HE-XRD SiO2-TiO2 melt
Development of a low-loss magnetic-coupling pickup for 166.6-MHz quarter-wave beta=1 superconducting cavities 认领
15
作者 Tong-Ming Huang Pei Zhang +5 位作者 Zhong-Quan Li Xin-Ying Zhang Hai-Ying Lin Qiang Ma Fan-Bo Meng Wei-Min Pan 《核技术:英文版》 SCIE CAS CSCD 2020年第9期25-32,共8页
166.6-MHz quarter-waveβ=1 superconducting cavities have been adopted for the High Energy Photon Source,a 6-GeV diffraction-limited synchrotron light source currently under construction.A large helium jacket was requi... 166.6-MHz quarter-waveβ=1 superconducting cavities have been adopted for the High Energy Photon Source,a 6-GeV diffraction-limited synchrotron light source currently under construction.A large helium jacket was required to accommodate the enlarged cavity beam pipe for the heavy damping of higher-order modes;the original electric-probe pickup thus becomes inevitably long with unfavorable mechanical properties.Relocated to an existing high-pressure-rinsing port,a magnetic-loop pickup was designed,characterized by low radio-frequency and cryogenic losses and being multipacting-free and insensitive to manufacturing and assembly tolerances.The consequent removal of the original pickup port from the cavity largely simplified the helium jacket fabrication and may also reduce cavity contamination.This paper presents a comprehensive design of a low-loss magnetic-coupling pickup for quarter-waveβ=1 superconducting cavities.The design can also be applied to other non-elliptical structures. 展开更多
关键词 PICKUP Magnetic coupling Quarter-wave cavity Superconducting cavity Low loss Synchrotron light source
在线阅读 下载PDF
Scheme for generating 1 nm X-ray beams carrying orbital angular momentum at the SXFEL 认领
16
作者 He-Ping Geng Jian-Hui Chen Zhen-Tang Zhao 《核技术:英文版》 SCIE CAS CSCD 2020年第9期33-44,共12页
Optical vortices have the main features of helical wavefronts and spiral phase structures,and carry orbital angular momentum.This special structure of visible light has been produced and studied for various applicatio... Optical vortices have the main features of helical wavefronts and spiral phase structures,and carry orbital angular momentum.This special structure of visible light has been produced and studied for various applications.These notable characteristics of photons were also tested in the extreme-ultraviolet and X-ray regimes.In this article,we simulate the use of a simple afterburner configuration by directly adding helical undulators after the SASE undulators with the Shanghai Soft X-ray FEL to generate high intensity X-ray vortices with wavelengths~1 nm.Compared to other methods,this approach is easier to implement,cost-effective,and more efficient. 展开更多
关键词 X-RAY Orbital angular momentum(OAM) Synchrotron light source Free-electron laser(FEL)
在线阅读 下载PDF
Micro and nanolattice fabrication using projection micro litho stereo exposure additive manufacturing techniques and synchrotron X-ray 3D imaging-based defect characterization 认领
17
作者 HU WenXia LIU LiWu +3 位作者 WU WenWang XI Li LENG JinSong FANG DaiNing 《中国科学:技术科学英文版》 SCIE EI CAS CSCD 2020年第4期561-570,共10页
Synchrotron radiation X-ray micro-computed tomography(SR-μCT)is a 3D imaging technique that is widely employed for the characterization of defects in advanced materials and structures.In this study,we characterize se... Synchrotron radiation X-ray micro-computed tomography(SR-μCT)is a 3D imaging technique that is widely employed for the characterization of defects in advanced materials and structures.In this study,we characterize several typical defects in octettruss and re-entrant 3D lattice structures by using SR-μCT.The 3D micro-lattice structures are manufactured using projection micro litho stereo exposure(PμLSE)additive manufacturing technology.The as-fabricated 3D lattice samples are characterized using optical microscopy,and subsequently,by SR-μCT.Further more,a statistical analysis is performed to characterize the surface roughness and internal defects qualitatively,whereby the statistical geometrical parameters of struts along different directions and strut joints are analyzed and classified.Consequently,several typical defects are identified:(1)holes at the joints of the strut and irregular diameter deviations of the strut in the octet-truss lattice structure;(2)irregular diameter variations,bulges,dislocations,grooves,accumulations,and torsion in the re-entrant lattice structure.All of these defects are related to the building direction,the weight of the structure,bubbles,dust,and impurities during the PμLSE additive manufacturing process. 展开更多
关键词 SYNCHROTRON radiation X-ray ADDITIVE manufacturing LATTICE structures defect characterization
Characterization of metal element distributions in the rat brain following ischemic stroke by synchrotron radiation microfluorescence analysis 认领
18
作者 Shu-Peng Shi Hui Wang +3 位作者 Zhuo-Hui Chen Xiao-Han Li Shi-Xin Liu Meng-Qi Zhang 《核技术:英文版》 SCIE CAS CSCD 2020年第10期1-12,共12页
Ischemic stroke is one of the leading causes of death worldwide,and effective treatment strategies in the chronic phase of this disease remain insufficient.Homeostasis of metals in the brain plays an important role in... Ischemic stroke is one of the leading causes of death worldwide,and effective treatment strategies in the chronic phase of this disease remain insufficient.Homeostasis of metals in the brain plays an important role in maintaining normal brain function.However,the dynamic spatial distributions of iron,zinc,calcium,potassium,and copper in a rat brain following ischemic stroke and the association between structural distribution and function remain to be elucidated.In this study,we used a synchrotron radiation-based micro-X-ray fluorescence technique to image element mapping changes in special rat brain regions after ischemic stroke,showing the distribution characteristics of iron,zinc,calcium,potassium,and copper.We demonstrated,for the first time,the consistent dynamic spatial distributions of metal elements at a series of time points(3 h,4.5 h,6 h,12 h,1 d,3 d,5 d,7 d,10 d,14 d,28 d)after brain ischemia,which revealed that the homeostasis of iron,zinc,calcium,potassium,and copper in the brain was disturbed with distinctive change trends,providing clear insights in understanding the underlying pathogenesis of stroke from a novel perspective,thus laying the foundation of further developing new drug targets for stroke treatment. 展开更多
关键词 Ischemic stroke Synchrotron radiation X-ray fluorescence METAL Rat brain
在线阅读 下载PDF
BL19U2:Small-angle X-ray scattering beamline for biological macromolecules in solution at SSRF 认领
19
作者 Yi-Wen Li Guang-Feng Liu +4 位作者 Hong-Jin Wu Ping Zhou Chun-Xia Hong Na Li Feng-Gang Bian 《核技术:英文版》 SCIE EI CAS CSCD 2020年第12期32-40,共9页
The BL19U2 at the Shanghai Synchrotron Radiation Facility is a small-angle X-ray scattering beamline dedicated to structural studies pertaining to biological macromolecules in solution.The beamline has been officially... The BL19U2 at the Shanghai Synchrotron Radiation Facility is a small-angle X-ray scattering beamline dedicated to structural studies pertaining to biological macromolecules in solution.The beamline has been officially opened to users in March 2015,and since then,a series of technological innovations has been developed to optimize beamline performance,thereby significantly improving the data collection efficiency and broadening the application scope of biological small-angle X-ray scattering.BL19U2 is ideal for the high-throughput screening of weakly scattered proteins,protein assemblies,nucleic acids,inorganic nanomaterials,and organic drug molecules.This paper describes the design and overview of the BL19U2 beamline.Versatile sample environments at the experimental station and some recent scientific highlights are presented. 展开更多
关键词 Shanghai synchrotron radiation facility Biological small-angle X-ray scattering High-throughput screening Biological macromolecules
在线阅读 下载PDF
三种电子加速器产生的臭氧危害分析 认领
20
作者 张震 李玉文 +2 位作者 陈飞 王雪涛 佟林全 《中国辐射卫生》 2020年第3期295-296,301,共3页
目的获得高能电子直线加速器、同步加速器和医用电子直线加速器产生的臭氧浓度,评估其臭氧危害。方法利用半经验公式分别计算三种常见电子加速器工作场所中臭氧浓度。结果三种不同类型电子加速器产生的臭氧浓度范围为2.21×10^−5~2.... 目的获得高能电子直线加速器、同步加速器和医用电子直线加速器产生的臭氧浓度,评估其臭氧危害。方法利用半经验公式分别计算三种常见电子加速器工作场所中臭氧浓度。结果三种不同类型电子加速器产生的臭氧浓度范围为2.21×10^−5~2.76×10^−1 mg/m^3。结论三种类型电子加速器产生的臭氧浓度均低于标准限值,正常工作条件下臭氧的职业病危害是能够有效控制的。 展开更多
关键词 臭氧浓度 高能电子直线加速器 同步加速器 医用电子直线加速器
上一页 1 2 79 下一页 到第
使用帮助 返回顶部 意见反馈