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The Crystal Structure Study of CaSrFe0.75Co0.75Mn0.5O6−δ by Neutron Diffraction
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作者 Amara Martinson Mandy Guinn Ram Krishna Hona 《Journal of Materials Science and Chemical Engineering》 2024年第1期29-35,共7页
The crystal structure of CaSrFe<sub>0.75</sub>Co<sub>0.75</sub>Mn<sub>0.5</sub>O<sub>6−δ</sub> is investigated through neutron diffraction techniques in this study. The... The crystal structure of CaSrFe<sub>0.75</sub>Co<sub>0.75</sub>Mn<sub>0.5</sub>O<sub>6−δ</sub> is investigated through neutron diffraction techniques in this study. The material is synthesized using a solid-state synthesis method at a temperature of 1200˚C. Neutron diffraction data is subjected to Rietveld refinement, and a comparative analysis with X-ray diffraction (XRD) data is performed to unravel the structural details of the material. The findings reveal that the synthesized material exhibits a cubic crystal structure with a Pm-3m phase. The neutron diffraction results offer valuable insights into the arrangement of atoms within the lattice, contributing to a comprehensive understanding of the material’s structural properties. This research enhances our knowledge of CaSrFe0.75</sub>Co0.75</sub>Mn0.5</sub>O6−δ</sub>, with potential implications for its applications in various technological and scientific domains. 展开更多
关键词 XRD Neutron diffraction Perovskite Oxides crystal structure Solid-State Reaction
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CRYSTAL STRUCTURE AND X-RAY POWDER DIFFRACTION DATA FOR RE COMPOUND HoNiSb 被引量:1
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作者 Zeng, Lingmin Li, Jungqin +2 位作者 Zhang, Liping Zhuang, Yinghong Hao, Jianmin (Institute of Materials Science, Guangxi University, Nanning 530004)(Tianjin Electronic Materzals Research Institute) 《中国有色金属学会会刊:英文版》 EI CSCD 1995年第3期71-73,共3页
CRYSTALSTRUCTUREANDX-RAYPOWDERDIFFRACTIONDATAFORRECOMPOUNDHoNiSb¥Zeng,Lingmin;Li,Jungqin;Zhang,Liping;Zhuang... CRYSTALSTRUCTUREANDX-RAYPOWDERDIFFRACTIONDATAFORRECOMPOUNDHoNiSb¥Zeng,Lingmin;Li,Jungqin;Zhang,Liping;Zhuang,Yinghong;Hao,Jia... 展开更多
关键词 RE COMPOUND HoNiSb x-ray diffraction data crystal structure
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X-ray Powder Diffraction Data and Crystal Structure of NiSbY
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作者 曾令民 李均钦 +2 位作者 张丽萍 庄应烘 郝建民 《Rare Metals》 SCIE EI CAS CSCD 1996年第1期67-70,共4页
X-ray powder diffraction data and crystal structure of NiSbY compound were studied by X-ray powderdiffraction. The compound belongs to the space group F43 m with MgAgAs structure type, and the parameters Z=4, a=0.6307... X-ray powder diffraction data and crystal structure of NiSbY compound were studied by X-ray powderdiffraction. The compound belongs to the space group F43 m with MgAgAs structure type, and the parameters Z=4, a=0.63075(2) nm. 展开更多
关键词 ANTIMONY crystal structure diffraction NICKEL X rays YTTRIUM
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Crystal Structure and X-ray Powder Diffraction Data for Rare Earth Compound PrNiSn
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作者 吴世伟 曾令民 +3 位作者 谭立真 张丽萍 严嘉琳 郝建民 《Rare Metals》 SCIE EI CAS CSCD 1999年第1期56-60,共5页
The compound PrNiSn was studied by X ray powder diffraction technique. The crystal structure and the X ray diffraction data for this compound at room temperature were reported. The compound PrNiSn is orthorhombic wi... The compound PrNiSn was studied by X ray powder diffraction technique. The crystal structure and the X ray diffraction data for this compound at room temperature were reported. The compound PrNiSn is orthorhombic with lattice parameters a =0.74569(3) nm, b =0.76851(5) nm, c =0.45676(8) nm, V =0.26176 nm 3, Z =4 and D x=8.076 g·cm -3 , space group Pna2 1(33). The figure of merit F N for the compound is F 30 =54 (0.0093, 60). 展开更多
关键词 PrNiSn X ray diffraction data crystal structure
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Structure of MgSO_4 in Concentrated Aqueous Solutions by X-Ray Diffraction 被引量:3
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作者 CAO Ling-di FANG Yah FANG Chun-hui 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2011年第3期490-495,共6页
Detailed time-and-space-averaged structure of MgSO4 in the concentrated aqueous solutions was investigated via X-ray diffraction with an X’pert Pro θ-θ diffractometer at 298 K, yielding structural function and radi... Detailed time-and-space-averaged structure of MgSO4 in the concentrated aqueous solutions was investigated via X-ray diffraction with an X’pert Pro θ-θ diffractometer at 298 K, yielding structural function and radial distribution function(RDF). The developed KURVLR program was employed for the theoretical investigation in consideration of the ionic hydration and ion association. Multi-peaks Gaussian fitting method was applied to deconvolving the overlapping bands of Differential radial distribution function(DRDF). The calculation of the geometric model shows that octahedrally six-coordinated Mg(H2O)62+, with an Mg2+…OW bond length of 0.201 nm dominates in the solutions. There exists contact ion-pair(CIP) in the more concentrated solution(1:18, H2O/salt molar ratio) with a coordination number of 0.8 and a characteristic Mg…S distance of 0.340 nm. The result indicates the hydrated SO42– ion happens in the solution. The S…OW bond distance was determined to be 0.382 nm with a coordination number of 13. The fraction of CIP increases significantly with the increasing concentration. The symmetry of the hydration structure of sulfate ion is lowered by forming complex with magnesium ion. 展开更多
关键词 Solution structure x-ray diffraction Magnesium sulfate Radial distribution function(RDF)
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Characterization of Average Molecular Structure of Heavy Oil Fractions by ~1H Nuclear Magnetic Resonance and X-ray Diffraction 被引量:2
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作者 Ren Wenpo Yang Chaohe Shan Honghong 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2011年第3期1-7,共7页
The chemical structure of heavy oil fractions obtained by liquid-solid adsorption chromatography was character-ized by 1 H nuclear magnetic resonance and X-ray diffraction.The molecular weight and molecular formula of... The chemical structure of heavy oil fractions obtained by liquid-solid adsorption chromatography was character-ized by 1 H nuclear magnetic resonance and X-ray diffraction.The molecular weight and molecular formula of asphaltene molecules were estimated by combining 1 H nuclear magnetic resonance and X-ray diffraction analyses,and were also ob-tained from vapor pressure osmometry and elemental analysis.Heteroatoms,such as S,N,and O atoms,were considered in the construction of average molecular structure of heavy oils.Two important structural parameters were proposed,including the number of alkyl chain substituents to aromatic rings and the number of total rings with heteroatoms.Ultimately,the av-erage molecular structures of polycyclic aromatics,heavy resins and asphaltene molecules were constructed.The number of α-,β-,γ-,and aromatic hydrogen atoms of the constructed average molecular structures fits well with the number of hydro-gen atoms derived from the experimental spectral data. 展开更多
关键词 heavy oil ASPHALTENE nuclear magnetic resonance (NMR) x-ray diffraction (XRD) average molecular structure
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Microstructure and strain analysis of GaN epitaxial films using in-plane grazing incidence x-ray diffraction 被引量:1
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作者 郭希 王玉田 +8 位作者 赵德刚 江德生 朱建军 刘宗顺 王辉 张书明 邱永鑫 徐科 杨辉 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第7期471-478,共8页
This paper investigates the major structural parameters, such as crystal quality and strain state of (001)-oriented GaN thin films grown on sapphire substrates by metalorganic chemical vapour deposition, using an in... This paper investigates the major structural parameters, such as crystal quality and strain state of (001)-oriented GaN thin films grown on sapphire substrates by metalorganic chemical vapour deposition, using an in-plane grazing incidence x-ray diffraction technique. The results are analysed and compared with a complementary out-of-plane x- ray diffraction technique. The twist of the GaN mosaic structure is determined through the direct grazing incidence t of (100) reflection which agrees well with the result obtained by extrapolation method. The method for directly determining the in-plane lattice parameters of the GaN layers is also presented. Combined with the biaxial strain model, it derives the lattice parameters corresponding to fully relaxed GaN films. The GaN epilayers show an increasing residual compressive stress with increasing layer thickness when the two dimensional growth stage is established, reaching to a maximum level of-0.89 GPa. 展开更多
关键词 in-plane grazing incidence x-ray diffraction gallium nitride mosaic structure biaxialstrain
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Ab initio Structure Determination of [Co(NH_3)_5Br]Br_2 Using Conventional X-ray Powder Diffraction 被引量:1
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作者 Hong Xiang WU and Li Dun MA(Center for Analysis and Measuremnt, Fudan University, Shanghai, 200433)(Project supported by the National Natural Science Foundation of China(NSFC) NO. 29573098) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第7期647-648,共2页
The crystal structure of [Co(NH3)5Br]Br2 has been determined ab initio from the conventional X-ray powder diffraction data. The approximate structure with all 7 indeyendent non-H atoms was solved by direct methods. Th... The crystal structure of [Co(NH3)5Br]Br2 has been determined ab initio from the conventional X-ray powder diffraction data. The approximate structure with all 7 indeyendent non-H atoms was solved by direct methods. The final orthorhombic unit-cell parameters after Rietveld refinement are: a=13.6927, b=10.7071, c=6.9400A, V=1017.47A3, F30=93(0.0075,43), M20=49, Z=4. Space group is Pnma. The structure agreement factors are: Rp=0.066,Rwp=0.090, RF=0.041, RB=0.042. 展开更多
关键词 Br2 Using Conventional x-ray Powder diffraction Ab initio structure Determination of NH3
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A Neutron Diffraction Study for the Crystal Structure of the Deuterium(hydrogen) L-Arginine Phosphate Monohydrate
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作者 Cheng Zhi-Xu Cheng Yu Fen Guo Li-Ping(China Institute of Atomic Energy,P.O.Box 275(30),Beijing 102413) 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 1995年第6期29-32,共4页
The crystal structure of the deuterium(hydrogen) L-arginine phosphate monohydrate D(H)LAP has been determined by neutron diffraction technique.[( D2N)2CND (CH2)3CH (ND3)CO2]+·[D2PO4]1-·D2O,Mr=302.3,monoclini... The crystal structure of the deuterium(hydrogen) L-arginine phosphate monohydrate D(H)LAP has been determined by neutron diffraction technique.[( D2N)2CND (CH2)3CH (ND3)CO2]+·[D2PO4]1-·D2O,Mr=302.3,monoclinic space group P21,Z=2,α=10.843(3),b=7.913(2),c=7.321(2),β=97.99(3)°,V=622.0(3),Dc=1.602 g/cm3.All atoms were located by block diagonal matrix least-squares technique.A final Rf value of 0.048 was obtained for 1040 observed independent reflections.The crystal structure consists of alternate layers of phosphate groups and arginine molecules stacked along the axis a and held together by hydrogen bonds. 展开更多
关键词 D(H) LAP NEUTRON diffraction crystal structure non-linear optics Characteristic
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CRYSTAL STRUCTURE OF A LONG-PERIOD ORDERED PHASE IN Fe-C MARTENSITE AND COMPUTER SIMULATION OF ITS ELECTRON DIFFRACTION PATTERNS
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作者 REN Xiaobing WANG Xiaotian +1 位作者 K.SHIMIZU T.TADAKI(National Laboratory of Solid State Microstructures,Nanjing University Nanjing 210093,China)(School of Materials Science and Engineering,Xi’an Jiaotong University Xi’an 710049,China)(Kanazawa Institute of Techn 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1996年第1期23-26,共4页
Different structure models of a long-period ordered phase in Fe-C martenstie formed during aging have been checked by computer simulation of electron diffraction(ED) patterns based on these models.The results showed t... Different structure models of a long-period ordered phase in Fe-C martenstie formed during aging have been checked by computer simulation of electron diffraction(ED) patterns based on these models.The results showed that the simulated ED pattern of γ'-FexC(Ⅱ) model proposed by the present authors is in good agreement with experimentally observed ED pattern.It was also confirmed that the incommensurate superperiod stems from the coexistence of several γ'-Fe_xC(H) phases with different superperiods.The Fe(144)C(24)(Fe6C) model proposed by Uwakweh et al.generated ED patterns remarkably different from the experimental ones. 展开更多
关键词 Fe-C martensite long-period ordered phase crystal structure computer simulation electron diffraction pattern
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Neutron Diffraction Study on Structure of α-LiIO_3 Single Crystal under DC Voltage
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作者 Cheng Yu-Fen Yang Zhen +1 位作者 Cheng Zhi-Xu Guo Li-Ping(China Institute of Atomic Energy,Beijing 102413)E.Legrand(SCK/CEN Boeretang 200 B-2400 Mol,Belgium) 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 1995年第6期11-14,共4页
A detailed investigation of anisotropy of neutron diffraction intensity enhancement observed in α-LiIO-3 single crystal under a DC field was carried out on a Four-Circle Neutron Diffractometer installed at the BR<... A detailed investigation of anisotropy of neutron diffraction intensity enhancement observed in α-LiIO-3 single crystal under a DC field was carried out on a Four-Circle Neutron Diffractometer installed at the BR<sub>2</sub> reactor in Belgium and CIAE reactor.It was found that the intensity increase must be ascribed to small displacements of oxygen and iodine atoms rather than the explanation which is only based on changes in the defect of the crystal structure,since the movement of lithium atom to interstitial sites or holes in the crystal may cause displacement of the other atoms. 展开更多
关键词 neutron diffraction single crystal structure α-LiIO3
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Liquid structure of pure iron by X-ray diffraction
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作者 JunLuo QijieZhai +1 位作者 PeiZhao XuboQin 《Journal of University of Science and Technology Beijing》 CSCD 2004年第2期161-164,共4页
The liquid structure of pure iron at 1540, 1560 and 1580 deg C was studied byX-ray diffraction. The results show that near the melting point there is a medium-range orderstructure that fades away with the increasing t... The liquid structure of pure iron at 1540, 1560 and 1580 deg C was studied byX-ray diffraction. The results show that near the melting point there is a medium-range orderstructure that fades away with the increasing temperature. The average nearest distance of atoms isalmost independent of the melts temperature, but the average coordination number, the atom clustersize and the atom number in an atom cluster all decrease with the increasing temperature of themelt. Near the melting point there are a lot of atom clusters in the pure iron melt. The atomcluster of pure iron has the body-centered cubic lattices, which are kept from the solid state. Andthe body-centered cubic lattices connect into network by occupying a same edge. The atoms in thesurrounding of the atom clusters are arranged disorderly. 展开更多
关键词 pure iron liquid structure x-ray diffraction
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Study of the Crystallographic and Magnetic Structure in the Nickel Substituted Cobalt Ferrites by Neutron Diffraction
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作者 Sadia Khanam A. K. M. Zakaria +9 位作者 M. H. Ahsan T. K. Datta S. Aktar S. I. Liba S. Hossain A. K. Das I. Kamal S. M. Yunus D. K. Saha S.-G. Eriksson 《Materials Sciences and Applications》 2015年第4期332-342,共11页
The polycrystalline spinel oxides NiX?Co1-X?Fe2O4 with composition x = 0.0, 0.2, 0.4, 0.6, 0.8 and 1.0 were prepared by conventional solid state ceramic sintering technique in air at 1300°C. X-ray diffraction exp... The polycrystalline spinel oxides NiX?Co1-X?Fe2O4 with composition x = 0.0, 0.2, 0.4, 0.6, 0.8 and 1.0 were prepared by conventional solid state ceramic sintering technique in air at 1300°C. X-ray diffraction experiments were carried out on all the samples at room temperature in order to characterize the materials. X-ray diffraction patterns showed sharp peaks indicating the formation of single phase cubic spinel structure. The neutron diffraction experiments were performed on all samples at room temperature, with an incident monochromatic neutron beam of wavelength λ = 1.5656 &Aring. The experimental neutron diffraction data were analyzed using the computer program FullProf in the Reitveld method. Reitveld refinement of the neutron diffraction data reveals that the samples possess cubic symmetry corresponding to the space group F d-3m. Cation distribution between the two sublattices of the spinel structure has been found from the analysis of the neutron diffraction data. Lattice parameters, oxygen position parameters, and overall temperature factors have also been determined from the analysis of neutron diffraction data. The lattice parameter decreases and oxygen position parameter increases with increasing Ni content in the system. Sublattices and net magnetic moments have been determined from the refinement of neutron diffraction data. The magnetic structure at room temperature was found to be ferrimagnetic for all the samples. 展开更多
关键词 Ferrites SPINEL structure crystal structure NEUTRON diffraction FERRIMAGNETIC
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Synthesis and X-ray Crystal Structure of a New Molecular Clip 被引量:4
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作者 佘能芳 高蒙 +1 位作者 王帅 吴安心 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2008年第7期777-780,共4页
The synthesis and X-ray crystal structure of a new molecular clip 2 was reported. It (C24H24N4O2, Mr = 400.47) crystallizes in the space group C2/c with a = 15.587(2), b = 8.5805(12), c = 15.259(2) A, β = 102... The synthesis and X-ray crystal structure of a new molecular clip 2 was reported. It (C24H24N4O2, Mr = 400.47) crystallizes in the space group C2/c with a = 15.587(2), b = 8.5805(12), c = 15.259(2) A, β = 102.448(3)°, V= 1992.9 (5)A63, Z = 4, Dc = 1.335 g/cm63,μ = 0.087 mm^-1 and F(000) = 848. It remains monomeric in the crystal and a tape-like structure is formed in the crystal structure of molecular clip. The most unusual structural feature of 2 is the boat conformation of its cyclohexyl ring imposed by the ring fusion at C(9)-C(9a). 展开更多
关键词 molecular clip x-ray crystal structure boat conformation
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Rietveld refinement of powder X-ray diffraction,microstructural and mechanical studies of magnesium matrix composites processed by high energy ball milling 被引量:2
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作者 T.Ramkumar M.Selvakumar +3 位作者 R.Vasanthsankar A.S.Sathishkumar P.Narayanasamy G.Girija 《Journal of Magnesium and Alloys》 SCIE EI CAS 2018年第4期390-398,共9页
This research reports the processing of magnesium matrix composites reinforced with silicon carbide(SiC)and aluminium oxide(Al_(2)O_(3))using powder metallurgy technique through high energy milling.Samples of Mg-SiC a... This research reports the processing of magnesium matrix composites reinforced with silicon carbide(SiC)and aluminium oxide(Al_(2)O_(3))using powder metallurgy technique through high energy milling.Samples of Mg-SiC and Mg-Al_(2)O_(3)composites subjected to high energy ball milling for different vol%of secondary particles 20,30 and 40%of SiC and Al_(2)O_(3)are studied by X-Ray diffraction technique.The rietveld method as implemented in the Fullprof program is applied in order to determine the quantities of the resulting crystalline phases and amorphous phases at each stage of the mechanical treatment.Microstructural examination is carried out using Scanning Electron Microscope(SEM).In addition,crystal structural analysis using appropriate size and strain models is performed in order to handle the distinctive anistrophy that is observed in convinced crystallographic directions for the magnesium composite.The results are furnished in terms of crystalline domains size enlargement of the magnesium composites phases upon prolonged milling duration and discussed in the light of up to date views and theories on crystal growth of nanocrystaline materials.The hardness of the composite samples is calculated by Vickers’s Hardness tester.Further,dry sling wear test and corrosion test are performed for the fabricated composites.Composite with 30%secondary particles incorporated magnesium composites exhibits better wear and corrosion resistance than the other composites. 展开更多
关键词 Rietveld refinement x-ray diffraction crystal structure Micro structure Wear and corrosion
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Ultrafast structural dynamics using time-resolved x-ray diffraction driven by relativistic laser pulses 被引量:2
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作者 Chang-Qing Zhu Jun-Hao Tan +7 位作者 Yu-Hang He Jin-Guang Wang Yi-Fei Li Xin Lu Ying-Jun Li Jie Chen Li-Ming Chen Jie Zhang 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第9期77-82,共6页
Based on a femtosecond laser plasma-induced hard x-ray source with a high laser pulse energy(>100 mJ)at 10 Hz repetition rate,we present a time-resolved x-ray diffraction system on an ultrafast time scale.The laser... Based on a femtosecond laser plasma-induced hard x-ray source with a high laser pulse energy(>100 mJ)at 10 Hz repetition rate,we present a time-resolved x-ray diffraction system on an ultrafast time scale.The laser intensity is at relativistic regime(2×10^(19)W/cm^(2)),which is essential for effectively generating K_(α)source in high-Z metal material.The produced copper K_(α)radiation yield reaches to 2.5×10^(8)photons/sr/shot.The multilayer mirrors are optimized for monochromatizating and two-dimensional beam shaping of Kαemission.Our experiment exhibits its ability of monitoring the transient structural changes in a thin film SrCoO_(2.5)crystal.It is demonstrated that this facility is a powerful tool to perform dynamic studies on samples and adaptable to the specific needs for different particular applications with high flexibility. 展开更多
关键词 ultrafast x-ray diffraction transient structural changes multilayer mirrors
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X-ray Multiple Diffraction Topographic Imaging Technique For Growth History Study of Habit Modifying Impurity Doped Crystals 被引量:1
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作者 LAI X. MA C. +1 位作者 K. J. Robert M. C. Miller 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2004年第4期411-416,共6页
A novel crystal characterization instrument has been built up in which a combination of X-ray multiple diffraction and X-ray topography is applied to enabling the cross-correlation between micro-crystallographic symme... A novel crystal characterization instrument has been built up in which a combination of X-ray multiple diffraction and X-ray topography is applied to enabling the cross-correlation between micro-crystallographic symmetry and its spatial dependence in relation to lattice defects. This facility is used to examine, in a self-consistent manner, growth sector-dependant changes to both the crystallographic structure and the lattice defects associated with the action of habit-modifying additives in a number of representative crystal growth systems. In addition, the new instrument can be used to probe micro-crystallographic aspects(such as distortion to crystal symmetry) and relate these in a spatially resolved manner to the crystal defect structure in crystals doped with known habit modifiers. 展开更多
关键词 x-ray diffraction x-ray multiple diffraction x-ray topography Habit modification crystal growth Growth defects
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X-ray and DFT Crystal Structure Determination and Conformational Analysis of a Pyrethroid Compound 被引量:1
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作者 YAHIAOUI Salem CHOUAIH Abdelkader HAMZAOUI Fodil 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2013年第10期1544-1552,共9页
The structure of (E)-N-[(E)-3-[(lR,2R)-2-(3,4-dibromo-phenyl)-l-fluro-cyclopropyl]- allylidene]-2-0-tolyl-acetamide (C21HIsONFBrz, Mr = 479.18) has been determined by X-ray single- crystal diffraction and th... The structure of (E)-N-[(E)-3-[(lR,2R)-2-(3,4-dibromo-phenyl)-l-fluro-cyclopropyl]- allylidene]-2-0-tolyl-acetamide (C21HIsONFBrz, Mr = 479.18) has been determined by X-ray single- crystal diffraction and theoretical calculations to establish the configuration, stereochemistry and a stable conformation of the molecule. The compound crystallizes in the monoclinic space group P21/c, a = 28.3452(10), b = 4.9311(10), c = 14.257(2) A, fl = 102.7654(10), V = 1943.5(5) A3 and Z = 4. The structure has been refined to the final R = 0.05 for the observed structure factors with 1 〉 30(/). Theoretical calculations in the ground state have been carried out for the compound studied using the Hartree-Fock (HF) and density functional theory (DFT) (B3LYP) with 6-31G(d,p) basis sets. The results show that the studied compound prefers the keto form. The compound involves intra- and intermolecular hydrogen bonding of C-H.-.O and C-H-..F types, which further stabilize the structure and display a trans configuration for the C=N and C=C double bonds. The calculated results show that the predicted geometry can well reproduce the structural parameters. 展开更多
关键词 x-ray diffraction crystal structure INSECTICIDE
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Neutron Diffraction Investigation of the DyFe11Ti Magnetic Structure and Its Spin Reorientations 被引量:1
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作者 Olivier Isnard Eder J.Kinast 《Engineering》 SCIE EI 2020年第2期154-158,共5页
In this article,we report on the magnetic structure of DyFe11Ti and its thermal evolution as probed by neutron powder diffraction.A thermodiffraction technique was used to follow the temperature dependence of the magn... In this article,we report on the magnetic structure of DyFe11Ti and its thermal evolution as probed by neutron powder diffraction.A thermodiffraction technique was used to follow the temperature dependence of the magnetic moments,as well as their orientation.The Dy and Fe moments were coupled to each other in an antiparallel manner to form a ferrimagnet,where the easy magnetization direction at 2 K was the[110]axis in the basal(a,b)plane.This magnetic structure underwent two successive spin reorientation phenomena with increasing temperature.A large Dy magnetic moment of 9.7 Bohr magneton(μB)was obtained at low temperatures,and the magnitude decreased rapidly to 7.5μB at 200 K.The largest Fe magnetic moment was observed on the Fe 8i position.A ThMn12-type crystal structure was preserved in the studied temperature range,despite the large changes of the magnetic structure.A sharp tilt was observed at the first-order spin reorientation,TSR1;the angle between the easy magnetization axis and the crystal c axis was reduced from 90°at 2 K to about 20°at 200 K(where c is the easy axis above 200 K);and the Dy and Fe magnetic moments maintained an antiparallel coupling. 展开更多
关键词 NEUTRON diffraction MAGNETIC PHASE DIAGRAM crystal structure
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Comparison between Double Crystals X-ray Diffraction and Micro-Raman Measurement on Composition Determination of High Ge Content Si_(1-x)Ge_(x) Layer Epitaxied on Si Substrate 被引量:1
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作者 Lei ZHAO Yuhua ZUO Buwen CHENG Jinzhong YU Qiming WANG 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2006年第5期651-654,共4页
It is important to acquire the composition of Si1-xGex layer, especially that with high Ge content, epitaxied on Si substrate. Two nondestructive examination methods, double crystals X-ray diffraction (DCXRD) and mi... It is important to acquire the composition of Si1-xGex layer, especially that with high Ge content, epitaxied on Si substrate. Two nondestructive examination methods, double crystals X-ray diffraction (DCXRD) and micro-Raman measurement, were introduced comparatively to determine x value in Si1-xGex layer, which show that while the two methods are consistent with each other when x is low, the results obtained from double crystals X-ray diffraction are not credible due to the large strain relaxation occurring in Si1-xGex layers when Ge content is higher than about 20%. Micro-Raman measurement is more appropriate for determining high Ge content than DCXRD. 展开更多
关键词 Si1-xGex Ge content Composition determination Double crystals x-ray diffraction (DCXRD) Micro-Raman measurement
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