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X-RAY POWDER DIFFRACTION DATA AND STRUCTURAL REFINEMENT OF Er3Co6Sn5
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作者 He, Wei Zeng, Lingmin +2 位作者 Qin, Wen Yan, Jialin Hao, Jianmin 《中国有色金属学会会刊:英文版》 EI CSCD 1999年第1期88-90,共3页
1INTRODUCTIONRaremetalsandtheircompoundshaveoutstandingpropertiesandarepaidincreasingatentionto.Numerousin... 1INTRODUCTIONRaremetalsandtheircompoundshaveoutstandingpropertiesandarepaidincreasingatentionto.Numerousinvestigationsinthe... 展开更多
关键词 ER 3Co 6Sn 5 x ray powder diffraction Rietveld STRUCTURAL REFINEMENT
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X-RAY POWDER DIFFRACTION DATA AND STRUCTURE REFINEMENT OF COMPOUND ErNi_2Si_2
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作者 Yan, JL Ou, XL Zeng, LM 《中国有色金属学会会刊:英文版》 CSCD 1998年第4期91-94,共4页
1INTRODUCTIONTherareearthcompoundsRET2Si2,whereREisarareearthelementandTisatransitionmetalelement,havebeenst... 1INTRODUCTIONTherareearthcompoundsRET2Si2,whereREisarareearthelementandTisatransitionmetalelement,havebeenstudiedwithgreatin?.. 展开更多
关键词 ErNi 2Si 2 x ray powder diffraction RIETVELD STRUCTURE REFINEMENT
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航天诱变育种第4代知母的XRF、PXRD分析 被引量:16
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作者 郭西华 关颖 +2 位作者 杨腊虎 王晓云 史锦珊 《药物分析杂志》 CAS CSCD 北大核心 2008年第12期2100-2102,共3页
目的:通过航天诱变选育优良的知母突变体,定向培育成药用部分品质提升的优良种质资源。方法:利用我国发射的神舟三号宇宙飞船搭载知母种子,回收后在地面上筛选繁育,并对枝叶和产量等方面占优势的第4代太空组及地面组知母药用部分中多种... 目的:通过航天诱变选育优良的知母突变体,定向培育成药用部分品质提升的优良种质资源。方法:利用我国发射的神舟三号宇宙飞船搭载知母种子,回收后在地面上筛选繁育,并对枝叶和产量等方面占优势的第4代太空组及地面组知母药用部分中多种元素含量用 X 射线荧光光谱(XRF)和粉末 X 射线衍射(PXRD)法测定并对比分析。结果:太空知母元素种类无改变,但 Zn、Sr 元素含量比地面组知母分别提高到2.7和1.7倍,Al 元素含量降低66.7%;并首次用 PXRD 技术在知母中鉴别出一水草酸钙晶体,太空知母中该晶体含量和晶粒尺寸比地面组明显减小。结论:航天诱变第4代知母中一水草酸钙晶体的含量明显减少,微量元素指标明显优化。通过航天诱变育种可以筛选出品质优化的知母新品种。 展开更多
关键词 航天诱变 知母 x射线荧光光谱(xRF) 粉末x射线衍射(pxrd)
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硒胁迫下彩叶草主要化学组分的FTIR和PXRD分析
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作者 袁菊红 胡绵好 《上海交通大学学报(农业科学版)》 2015年第2期39-46,共8页
为了阐明彩叶草(Coleus blumei Benth.)对硒(Se)胁迫的耐性机理,采用傅里叶变换红外光谱法(FTIR)和粉末X射线衍射法(PXRD)研究在不同Se浓度(0、0.1、0.5、1.0、2.5、5.0mg/L)处理下彩叶草根、茎、叶化学组分及其结构的变化。... 为了阐明彩叶草(Coleus blumei Benth.)对硒(Se)胁迫的耐性机理,采用傅里叶变换红外光谱法(FTIR)和粉末X射线衍射法(PXRD)研究在不同Se浓度(0、0.1、0.5、1.0、2.5、5.0mg/L)处理下彩叶草根、茎、叶化学组分及其结构的变化。结果表明,不同浓度Se处理下彩叶草各器官中化学组分的FTIR峰形基本不变,只有某些参与重金属吸收、转运及其积累的官能团如羟基(3 360~3 906cm^-1)、羧基(1 321~1 333cm^-1)、酰胺基(1 611~1 646cm^-1)、芳烃的C-H基(800~840cm^-1)及其C-Cl(618~706cm^-1)等的透射峰发生了不同程度的位移。彩叶草各器官中与植物生理有关的化学成分的特征峰大多数随Se浓度变化而变化。说明这些基团与Se的结合密切相关,进一步解释了彩叶草的耐Se及其在各器官积累Se的机理。不同浓度Se处理的彩叶草各器官物相结构主要组分以非晶体物质组分为主且均含有晶体成分,但处理浓度高低影响了其晶体物质组分含量的多少。 展开更多
关键词 彩叶草 硒胁迫 傅里叶变换红外光谱法(FTIR) 粉末x射线衍射分析(pxrd)
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EXAFS STUDY OF THE SHORT RANGE STRUCTURE OF NANOCRYSTALLINE BCC-Fe_(80)Cu_(20) SOLID SOLUTION 被引量:1
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作者 Y.Z. Yang, X.J. Bai, T.C. Kuang, G.M. Wang and S.Q. WeiFaculty of Materials and Energy, Guangdong University of Technology, Guangzhou 510090, ChinaCenter of Structure Analysis, University of Science and Technology of China, Hefei 230026, China Manuscript 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2002年第3期307-311,共5页
The structure of bcc-Fe80Cu20 solid solution produced by mechanical alloying of the elemental bcc-Fe and fcc-Cu powders has been studied using X-ray diffraction and the extended X-ray absorption fine structure (EXAFS)... The structure of bcc-Fe80Cu20 solid solution produced by mechanical alloying of the elemental bcc-Fe and fcc-Cu powders has been studied using X-ray diffraction and the extended X-ray absorption fine structure (EXAFS) techniques. The disappearance of elemental Fe and Cu X-ray diffraction (XRD) peaks and the presence of bcc structural XRD peaks illustrate the formation of a nanocrystalline single-phase bcc-Fe80Cu20 solid solution. From the EXAFS result, the clear observation of Cu atoms taking on bcc coordination in the solid solution and Fe atoms remaining bcc structure further verifies the reality of atomic alloying between Fe and Cu atoms and the lattice change of Cu from fcc to bcc. However, the supersaturated bcc solid solution is not chemically uniform, i.e., some regions are rich in Fe atoms and other regions rich in Cu atoms. 展开更多
关键词 COPPER powderS Solid solutions SUPERSATURATION x ray diffraction
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Unknown crystal structure determination from X-ray powder diffraction data
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作者 施颖 梁敬魁 +1 位作者 刘泉林 陈小龙 《Science China Mathematics》 SCIE 1998年第2期191-197,共7页
The crystal structure of new compound Ba 3BPO 7 has been solved by X ray powder diffraction technique. As a new structure type, the positions of barium, boron and phosphate atoms have been determined by single crystal... The crystal structure of new compound Ba 3BPO 7 has been solved by X ray powder diffraction technique. As a new structure type, the positions of barium, boron and phosphate atoms have been determined by single crystal direct method after profile decomposition from Ba 3BPO 7 X ray powder diffraction patterns. The positions of oxygen atoms have been determined by the interpretation of their vibration spectra which indicate that in this crystal the boron and phosphorus atoms form BO 3 and PO 4 polyhedra. The structure has been refined by Rietveld technique based on the above model. 展开更多
关键词 x ray powder diffraction crystal structure profile decomposition RIETVELD refinement.
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The crystal structures and physical properties of the solid solution compound Ba_5Y_(8-x)Mn_4O_(21-1.5x)(x = 0,1)
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作者 高庆庆 李静波 +4 位作者 宋士佳 饶光辉 骆军 刘广耀 梁敬魁 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第6期364-369,共6页
New oxometallides with the formula Ba5Y8-xMn4021-1.5x (x = 0, 1) are prepared through an atmosphere-controlled solid-state reaction. Two single-phase samples with Ba/Y/Mn atomic ratios 5/8/4 (Y8) and 5/7/4 (Y7)... New oxometallides with the formula Ba5Y8-xMn4021-1.5x (x = 0, 1) are prepared through an atmosphere-controlled solid-state reaction. Two single-phase samples with Ba/Y/Mn atomic ratios 5/8/4 (Y8) and 5/7/4 (Y7) are obtained. The crystal structures and the physical properties of the compounds are investigated by X-ray powder diffraction, magnetization, conductivity, and dielectricity measurements. The Ba5Y8-xMn4021-1.5x compound is demonstrated to be a Y-deficient solid solution. The solid solution compound Ba5Y8-xMn4021-1.5x crystallizes into tetragonal symmetry with the space group I4/m. Detailed structure analysis by Rietveld refinement of the X-ray powder diffraction data reveals that the Y vacancies occur preferentially at the Y(2) site. Thermal magnetization measurements indicate the presence of antiferromagnetic interaction between Mn ions in the compounds, and temperature-dependent resistivity measurements show that insulator-semiconductor transitions occur around 175 K and 170 K for the Y8 and Y7 samples, respectively. Strong frequency dependences of the dielectric constant are observed above -175 K for the two compounds. 展开更多
关键词 Ba5Y8-xMn4021-1.5x x-ray powder diffraction crystal structure CONDUCTIVITY
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Determination the content of gypsum fibrosum in Xiaokening tablets by powder X ray diffraction method 被引量:2
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作者 Jianping Zhang Xinxin Feng Dong Wang 《Journal of Chinese Pharmaceutical Sciences》 CAS CSCD 2019年第3期186-194,共9页
The research on the application of X-ray diffraction in the quantitative analysis of Chinese medicines is rare. The main reason is that the technical problems related to the internal standard and the selection of quan... The research on the application of X-ray diffraction in the quantitative analysis of Chinese medicines is rare. The main reason is that the technical problems related to the internal standard and the selection of quantitative peaks are not well solved, and the accuracy and precision of the results are not satisfactory. This study employed the concept of mass absorption coefficient based on the internal standard method, and the full spectrum fitting and quantitative methods were used to solve the above technical problems. The sample was blended. the internal standard substance of zinc oxide was fully ground, and tablets were prepared by positive pressure method. Under certain instrumental conditions, the PXRD pattern was obtained by scanning. The percentage of gypsum fibrosum in Xiaokening tablet was obtained by quantitative analysis of full spectrum fitting internal standard by TOPAS software. The method was investigated by methodology. At the same time, the method was compared by ion chromatography, and SPSS software was used to make a significant t test on the results of the two methods. After the investigation, the average standard recovery rate of CaSO4-2H2O was 99.06%(RSD = 3.02%);and the recovery rate for simulated samples was 96.7%. The method had good specificity. After statistical analysis, there was no significant difference between the new PXRD method and the traditional method of ion chromatography. 展开更多
关键词 powder x ray diffraction Full spectrum fitting internal standard quantitative method xiaokening tablet Gypsum fibrosum
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Characterization and Preparation of Ce-Zr-O Solid Solution 被引量:1
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作者 罗孟飞 周碧 +3 位作者 林瑞 陈敏 袁贤鑫 郑小明 《Journal of Rare Earths》 SCIE EI CAS CSCD 2000年第4期275-278,共4页
Ce Zr O solid solution was prepared by four different methods, i.e., decomposition of nitrate, coprecipiation, hydroxysuainic acid sol gel as well as citrate sol gel, and characterized by using X ray powder diffr... Ce Zr O solid solution was prepared by four different methods, i.e., decomposition of nitrate, coprecipiation, hydroxysuainic acid sol gel as well as citrate sol gel, and characterized by using X ray powder diffraction, Raman and temperature programmed reduction. The phase composition and the reduction properties of Ce Zr O depend on the preparation method. A cubic Ce 0.5 Zr 0.5 O 2 solid solution can be obtained by using the sol gel method. The Ce Zr O solid solution prepared by using decomposition or coprecipiation was composed of cubic Ce 0.8 Zr 0.2 O 2 and tetragonal Ce 0.2 Zr 0.8 O 2 solid solution. The Ce Zr O solid solution prepared with different methods shows the different reduction properties owing to different phase composition. Results of differential thermal analysis and XRD show that Ce 0.5 Zr 0.5 O 2 solid solution is formed during the decomposition or combustion of the gel. 展开更多
关键词 rare earths Ce 0.5 Zr 0.5 O 2 solid solution x ray powder diffraction RAMAN temperature programmed reduction
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MICROSTRUCTURAL CHANGE OF YSZ-SUPPORTED YBaCuO SUPPERCONDUCTING FILM BY PROTON BEAM BOMBARDMENTS
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作者 王广厚 罗成林 +7 位作者 潘国强 颜石乾 韩民 杨森祖 李元 吉争鸣 孙志坚 吴培亨 《Nuclear Science and Techniques》 SCIE CAS CSCD 1990年第3期129-136,共8页
Microstructural change of YBaCuO film/YSZ substrate with and without proton irradiation has been studied by scanning electron microscope and X- ray diffraction techniques. Structural analysis has shown that conversion... Microstructural change of YBaCuO film/YSZ substrate with and without proton irradiation has been studied by scanning electron microscope and X- ray diffraction techniques. Structural analysis has shown that conversion from tetragonal to orthorhombic phases, reduction of nonsuperconducting phase and preferential rearrangement of crystal grains are all favorable to the improvement of superconductivity in the YBaCuO film supported by YSZ substrate by proton beam bombardment. 展开更多
关键词 YBACUO superconducting FILM PROTON irradiation Scanning electron MICROSCOPE x - ray diffraction Conversion of PHASES
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Isothermal Section of the Cu-rich Cu-Be-Ag Ternary System
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作者 张丽萍 周开文 庄应烘 《Rare Metals》 SCIE EI CAS CSCD 1997年第3期73-76,共4页
The 500℃ isothermal section of the phase diagram of the Cu Be Ag (Cu≥50 at%) ternary system was investigated by X ray powder diffraction. The isothermal section consists of two single phase regions (namely α C... The 500℃ isothermal section of the phase diagram of the Cu Be Ag (Cu≥50 at%) ternary system was investigated by X ray powder diffraction. The isothermal section consists of two single phase regions (namely α Cu and CuBe), two two phase regions (namely α Cu+Ag and CuBe+α Cu) and one three phase region (namely α Cu+Ag+CuBe). The maximum solubility of Be in α Cu and Ag in α Cu are about 6.6 at% and 0.8 at% respectively. 展开更多
关键词 Phase diagram Cu Be Ag x ray powder diffraction
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Preparation and Characterization of Solid Dispersions of Silymarin with Polyethylene Glycol 6000 被引量:6
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作者 李凤前 胡晋红 姜远英 《Journal of Chinese Pharmaceutical Sciences》 CAS 2003年第2期76-81,共6页
Aim To prepare and characterize solid dispersions of silymarin with the intention of improving their dissolution properties. Methods The solid dispersions were prepared by the fusion method with polyethylene glycol ... Aim To prepare and characterize solid dispersions of silymarin with the intention of improving their dissolution properties. Methods The solid dispersions were prepared by the fusion method with polyethylene glycol 6000(PEG 6000) as the carrier. Evaluation of the properties of the dispersions was performed using dissolution studies, X ray powder diffraction and Fourier transform infrared (FT IR) spectroscopy. Results The rate of dissolution of silymarin was considerably improved as compared with pure silymarin when formulated in solid dispersions with PEG 6000. The data of the X ray diffraction showed some changes in the parameters of lattice spacing [ d ], peak position and relative intensities. FT IR together with those from X ray diffraction showed the absence of well defined drug polymer interactions. Conclusion The dissolution improvement of poorly soluble silymarin could be illuminated by the changes of the lattice parameters of PEG 6000 and the drug. 展开更多
关键词 SILYMARIN solid dispersions x ray powder diffraction FT IR spectroscopy DISSOLUTION PEG 6000
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5种丹参主要成分及微结构的检测及综合表征 被引量:10
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作者 郭西华 朱艳英 +6 位作者 王志宙 关颖 丁喜峰 王文静 叩根来 郝雪娟 程英杰 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2010年第8期2299-2302,共4页
利用X射线荧光(XRF)、粉末X射线衍射(PXRD)和傅里叶变换红外光谱(FTIR)分析技术,对安国栽培的5个不同种质丹参主要成分及微结构检测,对各样品中多种元素种类及含量、晶体及非晶体成分以一套综合特征图的方式对其表征;该谱将同种属不同... 利用X射线荧光(XRF)、粉末X射线衍射(PXRD)和傅里叶变换红外光谱(FTIR)分析技术,对安国栽培的5个不同种质丹参主要成分及微结构检测,对各样品中多种元素种类及含量、晶体及非晶体成分以一套综合特征图的方式对其表征;该谱将同种属不同种质丹参中的共有成分和细微差异之处给与直观地描述。3种技术共有制样简单,测定速度快,再现性和客观性好的特点;可用于药材优良品种的选育、中药材GAP种植条件的指导、药材产地特征、主要成分及微结构的检测及表征、质量稳定性的控制及真伪鉴别。 展开更多
关键词 xRF pxrd FTIR 丹参 质量控制
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乌桕类可可脂结晶膨胀过程中微观结构的变化 被引量:1
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作者 黄旭慧 熊涛 曾哲灵 《食品与发酵工业》 CAS CSCD 北大核心 2006年第12期48-51,共4页
结晶过程中乌桕类可可脂(CTCBE)的微观结构发生特殊变化,引起独特的立体膨胀现象。文中采用粉末X射线衍射法对比分析了CTCBE在15℃结晶3 h和5 h后的PXRD图谱,研究了CTCBE结晶膨胀过程中微观结构的变化。结果表明,在CTCBE结晶膨胀的过程... 结晶过程中乌桕类可可脂(CTCBE)的微观结构发生特殊变化,引起独特的立体膨胀现象。文中采用粉末X射线衍射法对比分析了CTCBE在15℃结晶3 h和5 h后的PXRD图谱,研究了CTCBE结晶膨胀过程中微观结构的变化。结果表明,在CTCBE结晶膨胀的过程中,外部和中部晶区晶面间距都具有增大的趋势,偏移量分别约为0.12?和0.10?。这说明甘油酸三酯分子之间间距的自发增大是引起CTCBE结晶膨胀的根本原因。 展开更多
关键词 乌桕类可可脂 粉末x射线衍射(pxrd) 结晶 膨胀 晶面间距
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Synthesis and Characterization of Methanesulfonate and Ethanesulfonate Intercalated Lithium Aluminum LDHs
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作者 Anton Niksch Herbert Pöllmann 《Natural Resources》 2021年第3期59-71,共13页
<span style="font-family:Verdana;"> <span style="font-family:;" "="">LDH-phases become increasingly interesting due to their broad ability to be able to incorporate many ... <span style="font-family:Verdana;"> <span style="font-family:;" "="">LDH-phases become increasingly interesting due to their broad ability to be able to incorporate many different cat</span><span style="font-family:;" "="">ions</span><span style="font-family:;" "=""> and anions. The intercalation of methanesulfonate and ethanesulfonate into a Li-LDH as well as the behavior of the interlayer structure as a function of the temperature is presented. A hexagonal P6<sub>3</sub>/m [LiAl<sub>2</sub>(OH)<sub>6</sub>][Cl?1</span><span style="font-family:;" "="">.</span><span style="font-family:;" "="">5H<sub>2</sub>O] (Li-Al-Cl) precursor LDH was synthesized by hydrothermal treating of a LiCl solution with <i>γ</i>-Al(OH)<sub>3</sub>. This precursor was used to intercalate methanesulfonate (CH<sub>3</sub>O<sub>3</sub>S<sup>?</sup>) and ethanesulfonate (C<sub>2</sub>H<sub>5</sub>O<sub>3</sub>S<sup>?</sup>) through anion exchange by stirring Li-Al-Cl in a solution of the respective organic Li-salt (90?C, 12 h). X-ray diffraction pattern showed an increase of the interlayer space <i>c</i></span><i><span style="font-family:;" "="">'</span></i><span style="font-family:;" "=""> (d<sub>001</sub>) of Li-Al-methanesulfonate (Li-Al-MS) with 1.2886 nm and Li-Al-ethanesulfonate (Li-Al-ES) with 1.3816 nm compared to the precursor with 0.7630 nm. Further investigations with Fourier-transform infrared spectroscopy and scanning electron microscopy confirmed a complete anion exchange of the organic molecules with the precursor Cl<sup>?</sup>. Both synthesized LDH compounds [LiAl<sub>2</sub>(OH)<sub>6</sub>]CH<sub>3</sub>SO<sub>3</sub>?nH<sub>2</sub>O (n = 2.24</span><span style="font-family:;" "="">-</span><span style="font-family:;" "="">3.72 (Li-Al-MS) and [LiAl<sub>2</sub>(OH)<sub>6</sub>]C<sub>2</sub>H<sub>5</sub>SO<sub>3</sub>}?nH<sub>2</sub>O (n = 1.5) (Li-Al-ES) showed a monomolecular interlayer structure with additional interlayer water at room temperature. By increasing the temperature, the interlayer water was removed and the interlayer space <i>c</i></span><i><span style="font-family:;" "="">'</span></i><span style="font-family:;" "=""> of Li-Al-MS decreased to 0.87735 nm (at 55?C). Calculations showed that a slight displacement of the organic molecules is necessary to achieve this interlayer space. Different behavior of Li-Al-ES could be observed during thermal treatment. Two phases coexisted at 75?C </span><span style="font-family:;" "="">-</span><span style="font-family:;" "=""> 85?C, one with a reduced <i>c</i></span><i><span style="font-family:;" "="">'</span></i><span style="font-family:;" "=""> (0.9015 nm, 75?C) and one with increased <i>c</i></span><i><span style="font-family:;" "="">'</span></i><span style="font-family:;" "=""> (1.5643 nm, 85?C) compared to the LDH compound at room temperature. The increase of <i>c</i></span><i><span style="font-family:;" "="">'</span></i><span style="font-family:;" "=""> is due to the formation of a bimolecular interlayer structure.</span><span style="font-family:;" "=""></span> <p> <br /> </p> </span><span style="font-family:Verdana;"></span><span style="font-family:;" "=""></span> 展开更多
关键词 LDH LITHIUM Aliphatic Sulfonic Acid x-ray powder diffraction High Temperature pxrd Layered Double Hydroxides SULFONATE
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真伪阿胶的X射线荧光分析及X射线衍射鉴别研究 被引量:14
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作者 关颖 郭西华 +4 位作者 杨腊虎 王志宙 邸立杰 朱二旷 王立鹏 《药物分析杂志》 CAS CSCD 北大核心 2009年第10期1658-1661,共4页
目的:建立和探索对阿胶及中药材既从整体上表征,又有定性又有量化指标的检定方法。方法:选择5个不同来源的阿胶样品与阿胶对照品进行对比分析。结果:XRF可对其宏量和微量元素的种类和含量进行测定,PXRD可对含有晶态物质的伪品阿胶进行... 目的:建立和探索对阿胶及中药材既从整体上表征,又有定性又有量化指标的检定方法。方法:选择5个不同来源的阿胶样品与阿胶对照品进行对比分析。结果:XRF可对其宏量和微量元素的种类和含量进行测定,PXRD可对含有晶态物质的伪品阿胶进行鉴别。结论:2种方法的联合应用可以从整体上对阿胶的元素指标和化合态这两方面进行质量控制和鉴别。这2种方法在阿胶、中药材及其饮片的检定标准制定方面具有较好的应用前景。 展开更多
关键词 阿胶 x射线荧光(xRF) 粉末x射线衍射(pxrd)
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