A new ternary compound,Mg_(11-x)Zn_(x)Sr in the Mg-Zn-Sr system was observed and studied using Scanning Electron Microscopy(SEM),Energy-Dispersive Spectroscope(EDS),X-Ray Diffraction(XRD)and Transmission Electron Micr...A new ternary compound,Mg_(11-x)Zn_(x)Sr in the Mg-Zn-Sr system was observed and studied using Scanning Electron Microscopy(SEM),Energy-Dispersive Spectroscope(EDS),X-Ray Diffraction(XRD)and Transmission Electron Microscopy(TEM).The XRD patterns were refined by the Rietveld refinement method and the results revealed that the crystallized Mg_(11-x)Zn_(x)Sr phase belonged to tetragonal I41/amd space group and had the Cd_(11)Ba prototype.The Mg atoms were successfully doped into Zn_(11)Sr crystal lattice by occupying Zn atomic sites.Moreover,the Rietveld refinement and computational results demonstrated a gradual decrease in the a-axis and c-axis lattice parameters with decreasing concentration levels of Mg coordination substitution in the lattice of Mg_(11-x)Zn_(x)Sr compound.The elastic constants and modulus of the Mg_(11-x)Zn_(x)Sr compounds calculated by first-principles calculations(FPC)indicated they were increased with the increasing of Zn content.The variation of hardness,D-band widths and the total density of states for Mg_(11-x)Zn_(x)Sr compounds with Zn content was discussed.展开更多
目的通过电感耦合等离子体质谱(inductively coupled plasma mass spectrometry,ICP-MS)法建立加味左金丸中Cd、Pb、As、Hg、Co、V、Ni、Cu、Li、Sb、Ba、Mo、Sn、Cr、Na、Mg、Al、Ca、Ti、Mn、Fe、Zn、Ga、Se、Sr、Tl共计26种无机元素...目的通过电感耦合等离子体质谱(inductively coupled plasma mass spectrometry,ICP-MS)法建立加味左金丸中Cd、Pb、As、Hg、Co、V、Ni、Cu、Li、Sb、Ba、Mo、Sn、Cr、Na、Mg、Al、Ca、Ti、Mn、Fe、Zn、Ga、Se、Sr、Tl共计26种无机元素的测定方法。方法加味左金丸通过微波消解法处理后,根据相对分子质量的大小选择内标物,其中^(7)Li、^(23)Na、^(24)Mg、^(27)Al、^(40)Ca、^(48)Ti、^(51)V、^(52)Cr、^(55)Mn、^(56)Fe、^(58)Ni、^(59)Co、^(63)Cu、^(66)Zn、^(70)Ga、^(75)As、^(77)Se、^(86)Sr以^(72)Ge作为内标;^(95)Mo、^(114)Cd、^(118)Sn、^(121)Sb、^(137)Ba以^(115)In作为内标;^(202)Hg、^(205)Tl、^(208)Pb以^(209)Bi作为内标。对标准品溶液、空白溶液与供试品溶液进行分析,采用标准曲线法进行定量分析。通过ICP-MS法进行测定。结果26种无机元素线性的相关系数r≥0.9996,检出限为0.001~1.500μg/L,定量限为0.01~5.00μg/L,精密度与重复性试验的RSD均小于5%,平均回收率在82.64%~106.44%,RSD均小于5%。对3个厂家的12批样品进行了测定,26种元素的含量差异较大,其中Na、Mg、Ca、Fe 4种元素的含量比较高,均大于500μg/g,Cd、Pb、As、Hg、Co、Li、Sb、Mo、Sn、Cr、Se、Tl的含量比较低,均小于1μg/g。由结果可知,人体的常量元素,如Na、Mg、Ca的含量比较高,Cd、Pb、As、Hg等有害元素含量比较低。根据《中国药典》2020年版一部的要求,本品中Cd、Pb、As、Hg与Cu均符合规定。结论该方法快速、准确,可以用于加味左金丸中无机元素的测定。展开更多
基金the National Key Research and Development Program of China(grant numbers 2018YFC1106702)the Natural Science Foundation of Guangdong Province,China(grant numbers 2020A1515011301,2018A0303100018 and 2018A030313950)+1 种基金Shenzhen Basic Research Project(grant numbers JCYJ20170815153143221,JCYJ20200109144608205 and JCYJ20170815153210359)IER Foundation(HT-JD-CXY-201902 and HT-JD-CXY201907)for financial support
文摘A new ternary compound,Mg_(11-x)Zn_(x)Sr in the Mg-Zn-Sr system was observed and studied using Scanning Electron Microscopy(SEM),Energy-Dispersive Spectroscope(EDS),X-Ray Diffraction(XRD)and Transmission Electron Microscopy(TEM).The XRD patterns were refined by the Rietveld refinement method and the results revealed that the crystallized Mg_(11-x)Zn_(x)Sr phase belonged to tetragonal I41/amd space group and had the Cd_(11)Ba prototype.The Mg atoms were successfully doped into Zn_(11)Sr crystal lattice by occupying Zn atomic sites.Moreover,the Rietveld refinement and computational results demonstrated a gradual decrease in the a-axis and c-axis lattice parameters with decreasing concentration levels of Mg coordination substitution in the lattice of Mg_(11-x)Zn_(x)Sr compound.The elastic constants and modulus of the Mg_(11-x)Zn_(x)Sr compounds calculated by first-principles calculations(FPC)indicated they were increased with the increasing of Zn content.The variation of hardness,D-band widths and the total density of states for Mg_(11-x)Zn_(x)Sr compounds with Zn content was discussed.
