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
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
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
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
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
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
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
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
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
<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
文摘目的: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。
基金Natural Science Foundation of Guangdong Province (Grant No. 20010056).
文摘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.
文摘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.
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 50872148 and 51072225)the National Basic Research Program of China (Grant No. 2007CB925003)
文摘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.
文摘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.
文摘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.
文摘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.
文摘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.
文摘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.
文摘<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>