大米中的微量元素种类及其含量多少与人体正常新陈代谢等生理功能密切相关，当人体摄入物质中含有过多有害的微量元素时，会严重的危害身体健康。本实验应用一种使用X光透镜的微束X射线荧光(Micro -XRF)分析技术，对5个不同产地大米中的微量元素进行了测定和分析，探讨不同产地大米中元素种类与含量之间的关系。并对其中一粒哈尔滨大米进行二维扫描，得出7种微量元素分布图。本研究建立了干灰化-XRF法测定大米中微量元素，采用干灰化消解制样和能量色散X荧光分析技术（EDXRF）分别测定5个不同产地大米中K、Ca、Ti、Co、Cr、Mn、Fe、Ni、Cu、Zn、As、Rb、Sr等13种金属元素含量。并与ICP-MS测定元素的结果相对比，用标准物质验证方法的准确度。实验表明，K、P在大米中含量较高远大于其他微量，P、Ca、Fe、Cu和Zn元素分布大致均匀，K、Cl元素主要富集在大米的前端，湖南大米和五常大米的特征产地元素可能是Si和Ni,干灰化-XRF对大米中微量元素具有富集作用，提高元素的探测极限，该方法简便、快速，适用于大米等粮食作物中金属元素的含量的测定，为食品微量元素的检测提供了一种新的方法和思路。

The concentrations of trace elements in rice are closely related to many metabolic functions in human body. Intaking many harmful trace elements will lead to the toxic effect on health. The trace elements of rice planted in five different areas are measured by Micro X-ray fluorescence analysis (Micro-XRF) technology.The types and concentrations of trace elements in rice planted in five different areas were discussed in detail. The concentrations distribution of trace elements are obtained through scanning the rice from Harbin.The method is established by combining the Ashing Digestion (ASD) of sample and XRF techniques (ASD-X RF) .Metal elements in rice (such as K, Ca, Ti, Co, Cr, Mn, Fe, Ni, Cu, Zn, As, Rb, Sr) are detected and analyzed by ASD-XRF techniques. By comparing with ICP-MS analysis on rice sample (GBW10045), the ASD-XRF has been verified an effective technique. Experimental results show that K and P concentrations are higher than other trace elements in rice. The trace elements in rice (such as P, Ca, Fe, Cu and Zn) distribute uniform roughly, K and Cl are mainly enriched in the front of the rice. Si concentrations of rice planted in Hunan and Ni concentrations planted in Wu Chang are higher than other regions. ASD - XRF is proved to be a simple and rapid technique in evaluting the concentrations of trace elements in food.