基于麦夸特算法的X射线衍射物相定量分析的影响因素研究
Study on the Influencing Factors of the Levenberg-Marquardt Algorithm for X-ray Diffraction Quantitative Phase Analysis
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摘要: X射线衍射物相定量分析方法很多,新近提出的麦夸特算法(Levenberg-Marquardt)在XRD物相定量分析中具有明显的优势,但在实际应用过程中,哪些因素会对该方法计算结果的准确度产生影响仍不清楚。为了指导实际操作过程并提高麦夸特算法在X射线衍射物相定量分析中的准确度和处理效率,本研究通过Matlab软件,将已知配比含量的刚玉、石英、方解石和钠长石与其计算值进行比较,探讨衍射峰强度、衍射峰背底、样品数量等因素对麦夸特算法应用于X射线衍射物相定量分析中计算结果的影响。结果表明:通过前三强峰法的计算结果比通过最强峰法的计算结果具有更高的准确度;由于物相晶体结构及衍射特性的差异,衍射峰背底对不同物相定量结果的影响程度各异,扣除背底后各物相计算结果的准确度整体上都有不同程度的提高;在利用麦夸特算法进行批量分析过程中,当样品数低于一定阈值时,样品数越多,计算结果的准确度提高越明显,但当计算的样品超过一定阈值时准确度不会有明显的提高。Abstract: There are many traditional methods of X-ray Diffraction (XRD) quantitative analysis. The latest developed Levenberg-Marquardt (LM) algorithm has the obvious advantages over traditional methods. However, it is still unclear which, and how, influencing factors affect the reliability and accuracy of the computed results in practice. In order to improve the accuracy and processing efficiency, the authors discuss influences of the choice of diffraction intensity, pattern background and sample numbers on phase quantitative analysis based on the LM method and Matlab program. A series of mixed minerals, which consist of corundum, quartz, calcite and albite, or bulk samples mixed with corundum under different proportions, were designed to examine the influences. The computed results from the sum of integral intensities of the top three peaks have improved accuracy over these by the integral intensity of the strongest peak. Some random errors are eliminated through the sum of integral intensities of the top three peaks effectively to some extent. The accuracies of the computed results were improved by background correction. Because of the differences in crystal structure and diffraction characteristics, the influences of background on the calculation results were different. The sample size also affects the accuracy of quantitative analyses using the LM method. Increasing samples can improve accuracy significantly if the number of samples is less than the threshold value, however, there is no obvious change if the number of samples is more than threshold value.
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Keywords:
- Levenberg-Marquardt /
- algorithm /
- X-ray /
- Diffraction /
- quantitative /
- analysis
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潘正君,康立山,陈毓屏.演化计算[M].北京:清华大学出版社, 1998: 23-116. Marquardt D W. An algorithm for least-squares estima-tion of nonlinear parameters[J]. Journal of Society Industry Apply Mathatic,1963,11(6): 431-441. Marquardt D W. An algorithm for least-squares estima-tion of nonlinear parameters[J]. Journal of Society Industry Apply Mathatic,1963,11(6): 431-441.
同济大学计算数学教研室.现代数值数学和计算[M].上海:同济大学出版社, 2004: 56-209. 谢政,李建华,汤泽潆.非线性最优化 [M].2版.长沙:国防科技大学出版社, 2003: 1-358. 晋勇,孙小松,薛屺.X射线衍射分析技术[M].北京:国防工业出版社, 2008: 1-56. 廖立兵,李国武.X射线衍射方法与应用[M].北京:地质出版社, 2007: 1-81. 刘粤惠,刘平安.X射线衍射分析原理与应用[M].北京:化学工业出版社, 2003: 1-77. 马礼敦.近代X射线多晶体衍射:实验技术与数据分析[M].北京:化学工业出版社, 2004: 1-256. 房俊卓,张霞,徐崇福.实验条件对X射线衍射物相定量分析结果的影响[J].岩矿测试, 2008,27(1): 60-62. Hill R J, Howard C J. Quantitative phase analysis from neutron powder diffraction using the Rietveld method[J]. Journal of Applied Crystallography,1987,20: 467-474. Hill R J, Howard C J. Quantitative phase analysis from neutron powder diffraction using the Rietveld method[J]. Journal of Applied Crystallography,1987,20: 467-474.
Young R A. The Rietveld Method [M]. Netherland: Oxford University Press, 1995: 1-308. Young R A. The Rietveld Method [M]. Netherland: Oxford University Press, 1995: 1-308.
储刚,翟秀静,符岩,毕诗文.X射线衍射多谱峰匹配强度比定量相分析方法[J].分析测试学报, 2004,23(1): 48-51. 曾蒙秀,宋友桂.麦夸特算法在X射线物相定量研究中的应用[J].地球科学——中国地质大学学报(已接收). 刘仕子.X射线衍射定量相分析的策略架构[J].岩矿测试, 2001,20(2): 81-87. 李建欣,宋党育,张军营,郑楚光.X射线衍射数据分析系统评价[J].岩矿测试, 2008,27(3): 189-192. 李传想,宋友桂,千琳勃,王乐民.中亚昭苏黄土剖面粒度记录的末次冰期以来气候变化历史[J]. 沉积学报, 2011,29(6): 1170-1179. 宋友桂,史正涛.伊犁盆地黄土分布与组成特征[J].地理科学, 2010,30(2): 267-272. 宋友桂,史正涛,方小敏,NIE Junsheng, NAOTO Ishikawa,强小科,王旭龙.伊犁黄土的磁学性质及其与黄土高原对比[J].中国科学:地球科学, 2010,40(1): 61-72. 马礼敦.X射线粉末衍射的新起点——Rietveld全谱拟合[J].物理学进展,1996,16(2): 251-265. 徐建平.莫来石中玻璃相含量的测定[J].理化检验:化学分册,2007,43(7): 605-606. 迟广成,张泉,赵爱林,钟辉,胡建飞.X射线粉晶衍射仪定量测量海泡石矿样的实验条件[J].岩矿测试, 2012,31(2): 282-286. 唐为华,刘敬魁,刘泉林.X射线粉末衍射法测定LaFe9Si4的晶体结构[J].自然科学进展,1997,7(5): 537-543. 谢义军,易礼均,李兴蓉,方淑芳.测试条件对08Al板ODF测算结果的影响[J].攀钢技术,2000,23(2): 41-46. 陈博钰.CSI模型样本量的Monte Carlo研究[J].统计与决策,2008(24): 17-19. 何振峰.一种基于限制的PAM算法[J].计算机工程与应用,2006(6): 190-192.
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