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High Resolution X-Ray Diffraction Analyses of (La,Sr)MnO<sub>3</sub>/ZnO/Sapphire(0001) Double Heteroepitaxial Films
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作者 Katsuhiko Inaba Shintaro Kobayashi +3 位作者 Kenichi Uehara Akira Okada Sanapa Lakshmi Reddy Tamio Endo 《Advances in Materials Physics and Chemistry》 2013年第1期72-89,共18页
The epitaxial relationships of lattices and crystalline qualities of LSMO/ZnO/sapphire double-hetero systems were thoroughly analyzed using X-ray diffraction techniques with a modern high resolution XRD system. It was... The epitaxial relationships of lattices and crystalline qualities of LSMO/ZnO/sapphire double-hetero systems were thoroughly analyzed using X-ray diffraction techniques with a modern high resolution XRD system. It was revealed that the epitaxial growth of the LSMO (110) phase was promoted under higher temperature accompanying the suppression of other competitive growth of the LSMO (001) and (111) phases. Supplying the plasma oxygen accelerated the suppression of the LSMO (111) phase. The complex epitaxial orientational relationships in these three growth modes were revealed from the precise analyses with the high resolution out-of-plane XRD and the in-plane XRD measurements, pole figure measurements, and reciprocal space mappings measurements, as [112ˉ](111)LSMO//[11ˉ00](0001)ZnO//[112ˉ0](0001)Sap, [110ˉ](111LSMO)//[11ˉ00](0001)Zno//[112ˉ0](0001)Sap, and [110](001)LSMO//[11ˉ00](0001)Zno//[112ˉ0](0001)Sap. The validity of this model for the epitaxial orientational relationships in LSMO/ZnO/sapphire double heteroepitaxial layers was confirmed identically with the data ana- lyses of the out-of-plane wide-range Reciprocal Space Mapping using the 2-dimensional X-ray detector. 展开更多
关键词 x-ray diffraction HETEROEPITAXY LSMO Orientational RELATIONS
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Synthesis and X-Ray Diffraction Analyses of Calcium Hydroxide Nanoparticles in Aqueous Suspension
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作者 G. Taglieri C. Mondelli +2 位作者 V. Daniele E. Pusceddu A. Trapananti 《Advances in Materials Physics and Chemistry》 2013年第1期108-112,共5页
Calcium hydroxide nanoparticles in aqueous suspensions (also called nanolime) were successfully employed in Cultural Heritage conservation thanks to the ability of favoring readhesion of the pictorial layer on origina... Calcium hydroxide nanoparticles in aqueous suspensions (also called nanolime) were successfully employed in Cultural Heritage conservation thanks to the ability of favoring readhesion of the pictorial layer on original carbonatic substrates or allowing to a better superficial cohesion and protection of treated stones. In this work, we have synthesized nanolime particles in aqueous suspension by two different methods. The produced particles were characterized in the laboratory, in terms of structural and morphological features, by means of X-Ray diffraction powder (XRD) and by transmission electron microscopy (TEM), respectively. Nanoparticles were crystalline, regularly shaped, hexagonally plated and with side dimensions generally ranging from 300 nm to 30 nm or less. Crystal structure of nanolime particles directly in the aqueous suspension, has been also analyzed by synchrotron diffraction from X-ray synchrotron radiation (SR-XRD);data have been analyzed by means of the Rietveld method and we have investigated the structure of Ca(OH)2 particles in suspension in terms of cell parameters, atomic coordinates, bond lengths and angles. 展开更多
关键词 NANOPARTICLES CALCIUM HYDROXIDE CRYSTAL Structure x-ray diffraction CRYSTAL Morphology
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Microstructures and micromechanical behaviors of high -entropy alloys investigated by synchrotron X-ray and neutron diffraction techniques: A review 被引量:1
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作者 Yubo Huang Ning Xu +3 位作者 Huaile Lu Yang Ren Shilei Li Yandong Wang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第6期1333-1349,共17页
High-entropy alloys(HEAs)possess outstanding features such as corrosion resistance,irradiation resistance,and good mechan-ical properties.A few HEAs have found applications in the fields of aerospace and defense.Exten... High-entropy alloys(HEAs)possess outstanding features such as corrosion resistance,irradiation resistance,and good mechan-ical properties.A few HEAs have found applications in the fields of aerospace and defense.Extensive studies on the deformation mech-anisms of HEAs can guide microstructure control and toughness design,which is vital for understanding and studying state-of-the-art structural materials.Synchrotron X-ray and neutron diffraction are necessary techniques for materials science research,especially for in situ coupling of physical/chemical fields and for resolving macro/microcrystallographic information on materials.Recently,several re-searchers have applied synchrotron X-ray and neutron diffraction methods to study the deformation mechanisms,phase transformations,stress behaviors,and in situ processes of HEAs,such as variable-temperature,high-pressure,and hydrogenation processes.In this review,the principles and development of synchrotron X-ray and neutron diffraction are presented,and their applications in the deformation mechanisms of HEAs are discussed.The factors that influence the deformation mechanisms of HEAs are also outlined.This review fo-cuses on the microstructures and micromechanical behaviors during tension/compression or creep/fatigue deformation and the application of synchrotron X-ray and neutron diffraction methods to the characterization of dislocations,stacking faults,twins,phases,and intergrain/interphase stress changes.Perspectives on future developments of synchrotron X-ray and neutron diffraction and on research directions on the deformation mechanisms of novel metals are discussed. 展开更多
关键词 high-entropy alloys MICROSTRUCTURES micromechanical behaviors synchrotron x-ray diffraction neutron diffraction
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Intensity correlation properties of x-ray beams split with Laue diffraction
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作者 赵昌哲 司尚禹 +3 位作者 张海鹏 薛莲 李中亮 肖体乔 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期379-383,共5页
Beam splitting is one of the main approaches to achieving x-ray ghost imaging, and the intensity correlation between diffraction beam and transmission beam will directly affect the imaging quality. In this paper, we i... Beam splitting is one of the main approaches to achieving x-ray ghost imaging, and the intensity correlation between diffraction beam and transmission beam will directly affect the imaging quality. In this paper, we investigate the intensity correlation between the split x-ray beams by Laue diffraction of stress-free crystal. The analysis based on the dynamical theory of x-ray diffraction indicates that the spatial resolution of diffraction image and transmission image are reduced due to the position shift of the exit beam. In the experimental setup, a stress-free crystal with a thickness of hundredmicrometers-level is used for beam splitting. The crystal is in a non-dispersive configuration equipped with a double-crystal monochromator to ensure that the dimension of the diffraction beam and transmission beam are consistent. A correlation coefficient of 0.92 is achieved experimentally and the high signal-to-noise ratio of the x-ray ghost imaging is anticipated.Results of this paper demonstrate that the developed beam splitter of Laue crystal has the potential in the efficient data acquisition of x-ray ghost imaging. 展开更多
关键词 x-ray ghost imaging beam splitting with Laue diffraction intensity correlation dynamical theory of x-ray diffraction
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Direct observation of shock-induced phase transformation in polycrystalline iron via in situ x-ray diffraction
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作者 Fan Zhang Jia-Qin Dong +11 位作者 Zhi-Yong Xie Zhi-Yu He Hua Shu Rui-Rong Wang Jun Xiong Guo Jia Zhi-Heng Fang Wei Wang Da-Wu Xiao An-Le Lei Jie Chen Xiu-Guang Huang 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第10期337-342,共6页
Phase transition of polycrystalline iron compressed along the Hugoniot is studied by combining laser-driven shock with in situ x-ray diffraction technique.It is suggested that polycrystalline iron changes from an init... Phase transition of polycrystalline iron compressed along the Hugoniot is studied by combining laser-driven shock with in situ x-ray diffraction technique.It is suggested that polycrystalline iron changes from an initial body-centered cubic structure to a hexagonal close-packed structure with increasing pressure(i.e.,a phase transition fromαtoε).The relationship between density and pressure for polycrystalline iron obtained from the present experiments is found to be in good agreement with the gas-gun Hugoniot data.Our results show that experiments with samples at lower temperatures under static loading,such as in a diamond anvil cell,lead to higher densities measured than those found under dynamic loading.This means that extrapolating results of static experiments may not predict the dynamic responses of materials accurately.In addition,neither the face-centered cubic structure seen in previous molecular-dynamics simulations or twophase coexistence are found within our experimental pressure range. 展开更多
关键词 in situ x-ray diffraction phase transition polycrystalline iron
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A Novel High Temperature Apparatus for in situ Synchrotron X-ray Diffraction Studies of Molten Salt
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作者 CAO Hui-li GAO Mei +5 位作者 Andebet G.Tamirat ZHAO Hong-bin ZHOU Xing-tai HUANG Yu-ying LEI Qi WEN Wen 《分析测试学报》 CAS CSCD 北大核心 2024年第10期1608-1617,共10页
This study demonstrates the design and application of a novel high temperature rotatory apparatus for insitu synchrotron X-ray diffraction studies of molten salts,facilitating investigation into the interaction betwee... This study demonstrates the design and application of a novel high temperature rotatory apparatus for insitu synchrotron X-ray diffraction studies of molten salts,facilitating investigation into the interaction between various structural materials and molten salts.The apparatus enables accurate detection of every phase change during hightemperature experiments,including strong reaction processes like corrosion.Molten salts,such as chlorides or fluo⁃rides,together with the structure materials,are inserted into either quartz or boron nitride capillaries,where X-ray diffraction pattern can be continuously collected,as the samples are heated to high temperature.The replacement re⁃action,when molten ZnCl2 are etching Ti3AlC2,can be clearly observed through changes in diffraction peak intensity as well as expansion in c-axis lattice parameter of the hexagonal matrix,due to the larger atomic number and ionic ra⁃dius of Zn2+.Furthermore,we investigated the high-temperature corrosion process when GH3535 alloy is in FLiNaK molten salt,and can help to optimize its stability for potential applications in molten salt reactor.Additionally,this high temperature apparatus is fully compatible with the combined usage of X-ray diffraction and Raman technique,providing both bulk and surface structural information.This high temperature apparatus has been open to users and is extensively used at BL14B1 beamline of the Shanghai Synchrotron Radiation Facility. 展开更多
关键词 in-situ x-ray diffraction rotary micro-diffractometer rotary high-temperature apparatus molten salt
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Tracking the phase transformation and microstructural evolution of Sn anode using operando synchrotron X-ray energy-dispersive diffraction and X-ray tomography 被引量:1
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作者 Kang Dong Fu Sun +4 位作者 Andre Hilger Paul H.Kamm Markus Osenberg Francisco Garcia-Moreno Ingo Manke 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第1期429-437,I0011,共10页
Tin(Sn)holds great promise as an anode material for next-generation lithium(Li)ion batteries but suffers from massive volume change and poor cycling performance.To clarify the dynamic chemical and microstructural evol... Tin(Sn)holds great promise as an anode material for next-generation lithium(Li)ion batteries but suffers from massive volume change and poor cycling performance.To clarify the dynamic chemical and microstructural evolution of Sn anode during lithiation and delithiation,synchrotron X-ray energydispersive diffraction and X-ray tomography are simultaneously employed during Li/Sn cell operation.The intermediate Li-Sn alloy phases during de/lithiation are identified,and their dynamic phase transformation is unraveled which is further correlated with the volume variation of the Sn at particle-and electrode-level.Moreover,we find that the Sn particle expansion/shrinkage induced particle displacement is anisotropic:the displacement perpendicular to the electrode surface(z-axis)is more pronounced compared to the directions(x-and y-axis)along the electrode surface.This anisotropic particle displacement leads to an anisotropic volume variation at the electrode level and eventually generates a net electrode expansion towards the separator after cycling,which could be one of the root causes of mechanical detachment and delamination of electrodes during long-term operation.The unraveled chemical evolution of Li-Sn and deep insights into the microstructural evolution of Sn anode provided here could guide future design and engineering of Sn and other alloy anodes for high energy density Li-and Na-ion batteries. 展开更多
关键词 Sn anode Li-Sn phase transformation x-ray tomography Operando x-ray diffraction Anisotropic displacement Digital volume correlation(DVC)
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Thermal expansivity of geikielite and ilmenite utilizing in-situ synchrotron X-ray diffraction at high temperature
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作者 Jiamei Song Dawei Fan +4 位作者 Shijie Huang Shanrong Zhang Mengzeng Wu Wei Chen Wenge Zhou 《Acta Geochimica》 EI CAS CSCD 2023年第6期988-997,共10页
The unit-cell parameters and volumes of geikielite(MgTiO_(3))and ilmenite(FeTiO_(3))were investigated at high temperatures up to 700 K and ambient pressure,using in-situ angle-dispersive synchrotron X-ray diffraction.... The unit-cell parameters and volumes of geikielite(MgTiO_(3))and ilmenite(FeTiO_(3))were investigated at high temperatures up to 700 K and ambient pressure,using in-situ angle-dispersive synchrotron X-ray diffraction.No phase transition was detected over the experimental temperature range.Using(Berman in J Petrol29:445-522,1988.10.1093/petrology/29.2.445)equations to fit the temperature-volume data,the volumetric thermal expansion coefficients at ambient conditions(α_(V0))of MgTiO_(3) and FeTiO_(3) were obtained as follows:2.55(6)×10^(-5)K^(-1)and 2.82(10)×10^(-5)K^(-1),respectively.We infer that the larger effective ionic radius of Fe^(2+)(Ⅵ)(0.78 A)than that of Mg^(2+)(Ⅵ)(0.72?)renders FeTiO_(3)has a larger volumetric thermal expansivity than MgTiO_(3).Simultaneously,the refined axial thermal expansion coefficients under ambient conditions areα_(a0)=0.74(3)×10^(-5)K^(-1)andα_(c0)=1.08(5)×10^(-5)K^(-1)for the aaxis and c-axis of MgTiO_(3),respectively,andα_(a0)=0.95(5)×10^(-5)K^(-1)andα_(c0)=0.92(12)×10^(-5)K^(-1)for the aaxis and c-axis of FeTiO_(3),respectively.The axial thermal expansivity of MgTiO_(3) is anisotropic,but that of FeTiO_(3) is nearly isotropic.We infer that the main reason for the different axial thermal expansivity between MgTiO_(3) and FeTiO_(3) is that the thermal expansion mode of the Mg-O bond in MgTiO_(3) is different from that of the Fe-O bonds in FeTiO_(3). 展开更多
关键词 Geikielite ILMENITE Thermal expansion Synchrotron x-ray diffraction High temperature
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MULTI-PEAK MATCH INTENSITY RATIO METHOD OF QUANTI-TATIVE X-RAY DIFFRACTION PHASE ANALYSIS 被引量:5
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作者 G. Chu, Y.F. Cong and H.J. YouResearch Center of Analysis and Test, Liaoning University of Petroleum & Chemical Technology, Fushun 113001, China 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2003年第6期489-494,共6页
A new method for quantitative phase analysis is proposed by using X-ray diffraction multi-peak match intensity ratio. This method can obtain the multi-peak match intensity ratio among each phase in the mixture sample ... A new method for quantitative phase analysis is proposed by using X-ray diffraction multi-peak match intensity ratio. This method can obtain the multi-peak match intensity ratio among each phase in the mixture sample by using all diffraction peak data in the mixture sample X-ray diffraction spectrum and combining the relative intensity distribution data of each phase standard peak in JCPDS card to carry on the least square method regression analysis. It is benefit to improve the precision of quantitative phase analysis that the given single line ratio which is usually adopted is taken the place of the multi-peak match intensity ratio and is used in X-ray diffraction quantitative phase analysis of the mixture sample. By analyzing four-group mixture sample, adopting multi-peak match intensity ratio and X-ray diffraction quantitative phase analysis principle of combining the adiabatic and matrix flushing method, it is tested that the experimental results are identical with theory. 展开更多
关键词 x-ray diffraction multi-peak match intensity ratio quantitative phase analysis
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Analysis of surface orange peel of aluminum-alloy automobile sheet by using of EBSD and X-ray diffraction 被引量:7
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作者 Ma Mingtu Sun Zhifu +2 位作者 Wang Zhiwen Lu Hongzhou Zhou Mingbo 《Engineering Sciences》 EI 2012年第6期7-11,37,共6页
The formation cause of orange peel of aluminum-alloy automotive sheet after tensile deformation was analysed by using X-ray diffraction and electron back-scattered diffraction(EBSD).The test results showed that format... The formation cause of orange peel of aluminum-alloy automotive sheet after tensile deformation was analysed by using X-ray diffraction and electron back-scattered diffraction(EBSD).The test results showed that formation cause of surface orange peel after tensile deformation related to product texture and nonuniform deformation during the tensile process.The grain size has significant effect on deformation uniform and texture formation.Coarse grains were easy to produce nonuniform deformation and texture,which would produce surface orange peel after tensile deformation. 展开更多
关键词 ALUMINUM-ALLOY automotive sheet orange peel TEXTURE EBSD x-ray diffraction
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Operando X-ray diffraction analysis of the degradation mechanisms of a spinel LiMn2O4 cathode in different voltage windows 被引量:2
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作者 Fakui Luo Congcong Wei +6 位作者 Chi Zhang Hui Gao Jiazheng Niu Wensheng Ma Zhangquan Peng Yanwen Bai Zhonghua Zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2020年第5期138-146,共9页
The understanding of reaction mechanisms of electrode materials is of significant importance for the development of advanced batteries.The LiMn2O4 cathode has a voltage plateau around 2.8 V(vs.Li^+/Li),which can provi... The understanding of reaction mechanisms of electrode materials is of significant importance for the development of advanced batteries.The LiMn2O4 cathode has a voltage plateau around 2.8 V(vs.Li^+/Li),which can provide an additional capacity for Li storage,but it suffers from a severe capacity degradation.In this study,operando X-ray diffraction is carried out to investigate the structural evolutions and degradation mechanisms of LiMn2O4 in different voltage ranges.In the range of 3.0-4.3 V(vs.Li^+/Li),the LiMn2O4 cathode exhibits a low capacity but good cycling stability with cycles up to 100 cycles and the charge/discharge processes are associated with the reversible extraction/insertion of Li^+from/into LixMn2O4(0≤x≤1).In the range of 1.4-4.4 V(vs.Li^+/Li),a capacity higher than 200 mAh/g is achieved,but it rapidly decays during the cycling.The voltage plateau around 2.8 V(vs.Li^+/Li)is related to the transformation of the cubic LiMn2O4 phase to the tetragonal Li2Mn2O4 phase,which leads to the formation of cracks as well as the performance degradation. 展开更多
关键词 LITHIUM-ION BATTERY OVER-DISCHARGE Phase transition CATHODE OPERANDO x-ray diffraction
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In situ X-ray diffraction and thermal analysis of LiNi0.8Co0.15Al0.05O2 synthesized via co-precipitation method 被引量:2
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作者 Na Zhang Xiaoyu Zhang +7 位作者 Erbo Shi Shiyong Zhao Kezhu Jiang Di Wang Pengfei Wang Shaohua Guo Ping He Haoshen Zhou 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2018年第6期1655-1660,共6页
LiNi0.9Co0.15Al0.05O2 (NCA) material is successfully synthesized with a modified co-precipitation method,in which NH3,H2O and EDTA are used as two chelating agents. The obtained LiNi0.9Co0.15Al0.05O2 materialhas wel... LiNi0.9Co0.15Al0.05O2 (NCA) material is successfully synthesized with a modified co-precipitation method,in which NH3,H2O and EDTA are used as two chelating agents. The obtained LiNi0.9Co0.15Al0.05O2 materialhas well-defined layered structure and uniform element distribution, which reveals an enhanced electro-chemical performance with a capacity retention of 97.9% after 100 cycles at 0.2 C, and reduced thermalrunaway from the isothermal calorimetry test. In situ X-ray diffraction (XRD) was employed to capturethe structural changes during the charge-discharge process. The reversible evolutions of lattice parame-ters (a, b, c, and V) further verify the structural stability. 展开更多
关键词 LiNi0.9Co0.15Al0.05O2 CO-PRECIPITATION Isothermal calorimetry Insitu x-ray diffraction
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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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Fitting Full X-Ray Diffraction Patterns for Quantitative Analysis: A Method for Readily Quantifying Crystalline and Disordered Phases 被引量:3
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作者 Steve J. Chipera David L. Bish 《Advances in Materials Physics and Chemistry》 2013年第1期47-53,共7页
Fitting of full X-ray diffraction patterns is an effective method for quantifying abundances during X-ray diffraction (XRD) analyses. The method is based on the principal that the observed diffraction pattern is the s... Fitting of full X-ray diffraction patterns is an effective method for quantifying abundances during X-ray diffraction (XRD) analyses. The method is based on the principal that the observed diffraction pattern is the sum of the individual phases that compose the sample. By adding an internal standard (usually corundum) to both the observed patterns and to those for individual pure phases (standards), all patterns can all be normalized to an equivalent intensity based on the internal standard intensity. Using least-squares refinement, the individual phase proportions are varied until an optimal match is reached. As the fitting of full patterns uses the entire pattern, including background, disordered and amorphous phases are explicitly considered as individual phases, with their individual intensity profiles or “amorphous humps” included in the refinement. The method can be applied not only to samples that contain well-ordered materials, but it is particularly well suited for samples containing amorphous and/or disordered materials. In cases with extremely disordered materials where no crystal structure is available for Rietveld refinement or there is no unique intensity area that can be measured for a traditional RIR analysis, full-pattern fitting may be the best or only way to readily obtain quantitative results. This approach is also applicable in cases where there are several coexisting highly disordered phases. As all phases are considered as discrete individual components, abundances are not constrained to sum to 100%. 展开更多
关键词 Full-Pattern QUANTITATIVE x-ray diffraction XRD
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Powder x-ray diffraction and Rietveld analysis of (C_(2)H_(5)NH_(3))_(2)CuCl_(4) 被引量:2
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作者 Yi Liu Jun Shen +2 位作者 Zunming Lu Baogen Shen Liqin Yan 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第6期58-61,共4页
Structural properties of the organic-inorganic hybrid(C_(2)H_(5)NH_(3))_(2)CuCl_(4) have been investigated by means of x-ray powder diffraction and Rietveld analysis. A structural phase transition from Pbca to Aba2 oc... Structural properties of the organic-inorganic hybrid(C_(2)H_(5)NH_(3))_(2)CuCl_(4) have been investigated by means of x-ray powder diffraction and Rietveld analysis. A structural phase transition from Pbca to Aba2 occurs at T_(4)= 240 K, which results in a paraelectric–ferroelectric phase transition. The release of the Jahn–Teller distortion with increasing temperature toward T_(4) is revealed by the structural analysis. 展开更多
关键词 organic-inorganic hybrid x-ray diffraction (C_(2)H_(5)NH_(3))_(2)CuCl_(4)
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Preparation, crystallization and preliminary X-ray diffraction analysis of PH1948, predicted RNA methyltransferase from Pyrococcus horikoshii
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作者 高永贵 姚闵 TANAKA Isao 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE EI CAS CSCD 2005年第6期454-456,共3页
RNA methyltransferase is responsible for transferring methyl and resulting in methylation on the bases or ribose ring of RNA, which existed widely but mostly remains an open question. A recombinant protein PH1948 pred... RNA methyltransferase is responsible for transferring methyl and resulting in methylation on the bases or ribose ring of RNA, which existed widely but mostly remains an open question. A recombinant protein PH1948 predicting RNA methyl- transferase from Pyrococcus horikoshii OT3 has been crystallized. The crystals of selenomethionyl PH1948 belong to space group C2, with unit-cell parameters a=207.0 ?, b=43.1 ?, c=118.2 ?, β=92.1°, and diffract X-rays to 2.2 ? resolution. The VM value was determined to be 2.8 ?3/Da, indicating the presence of four protein molecules in the asymmetric unit. 展开更多
关键词 Pyrococcus horikoshii METHYLTRANSFERASE x-ray diffraction Protein crystallography
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AN INCREMENTAL METHOD OF X-RAY DIFFRACTION QUANTITATIVE PHASE ANALYSIS OF SAMPLESCONTAINING AMORPHOUS MATERIAL
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作者 G. Chu(Department of Applied Chemistry Fushun Petroleum Institute, Fushun 113001, China) 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1997年第1期35-38,共4页
A new method for quantitative X-ray diffraction phase analysis of a powder misture has been developed according to Popovic's doping method. The weight fraction of amorphous material in the analysed sample is obtai... A new method for quantitative X-ray diffraction phase analysis of a powder misture has been developed according to Popovic's doping method. The weight fraction of amorphous material in the analysed sample is obtained. For a multicomponent system in which (n-2) pure phases are added into an n-phase compnent sample and theweight fractions of all n phases can be determined by the method. The test results of confirmation agree well with the theory. 展开更多
关键词 x-ray diffraction quantitative phase analysis amorphous material mass absorption coefficient
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A SOLUTION OF MINIMUM NORM FOR QUANTITATIVE PHASE ANALYSIS BY STANDARDLESS X-RAY DIFFRACTION
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作者 ZHAO Han GONG Yansheng SHEN Jingyuan RUAN Qikuan JIN Jialing ZHU Hanyu Research Institute of Qiqihar Steel Works,Fulaerji,China GONG Yansheng Senior Engineer,Research Institute of Qiqihar Steel Works,Filaerji 161041,China 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1990年第9期225-229,共5页
A new expression of quantitative phase analysis by standardless X-ray diffraction has been derived using intensity matrix of vector modulus,The criterion of standardless X-ray diffraction analysis was suggested,so as ... A new expression of quantitative phase analysis by standardless X-ray diffraction has been derived using intensity matrix of vector modulus,The criterion of standardless X-ray diffraction analysis was suggested,so as to separate the diffraction pattern of every phase from that of sample.The optimal solution could be obtained by the least squares regression. 展开更多
关键词 x-ray diffraction standardless phase analysis least square regression
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A SOLUTION OF MINIMUM NORM FOR QUANTITATIVE PHASE ANALYSIS BY STANDARDLESS X-RAY DIFFRACTION
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作者 ZHAO Han GONG Yansheng SHEN Jingyuan RUAN Qikuan JIN Jialing ZHU Hanyu Research Institute of Qiqihar Steel Works,Fulaerji,China 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1991年第9期225-229,共5页
A new expression of quantitative phase analysis by standardless X-ray diffraction has been derived using intensity matrix of vector modulus.The criterion of standardless X-ray diffraction analysis was suggested,so as ... A new expression of quantitative phase analysis by standardless X-ray diffraction has been derived using intensity matrix of vector modulus.The criterion of standardless X-ray diffraction analysis was suggested,so as to separate the diffraction pattern of every phase from that of sample.The optimal solution could be obtained by the least squares regression. 展开更多
关键词 x-ray diffraction standardless phase analysis least square regression
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THE DEGREE OF CRYSTALLINITY OF MULTICOMPONENT POLYMERS BY X-RAY DIFFRACTION ANALYSIS
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作者 Zhi Shen MO Bao Quan YANO Hong Tang ZHANO Changchun Institute of Applied Chemistry,Academia Sinica,Changchun 130022 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第4期323-324,共2页
Based on the X-ray scattering intensity theory,the correction factors of the degree of crystallinity formulae of the multicomponent polymers have been clearly defined.The formula of degree of erystallinity of the mult... Based on the X-ray scattering intensity theory,the correction factors of the degree of crystallinity formulae of the multicomponent polymers have been clearly defined.The formula of degree of erystallinity of the multicomponent polymers was derived in terms of the WAXD theory ahd improved graphic multipeak resolution methods.The results calculated are compatible with the density measurement. 展开更多
关键词 PP HO Li ZHANG THE DEGREE OF CRYSTALLINITY OF MULTICOMPONENT POLYMERS BY x-ray diffraction analysIS POLY
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