摘要
X射线荧光光谱法(XRF)是地球化学标准物质均匀性检验的重要方法之一,但目前应用XRF法对标准物质进行均匀性检验还存在争议。由于均匀性检验要求称样量为最小取样量,而采用常规粉末压片或熔融制样进行XRF均匀性检验时称样量一般均大于最小取样量,得到的结果在理论上不足以支撑样品在最小取样量条件下是否均匀。本研究称取0.1 g样品,以四硼酸锂、偏硼酸锂和氟化锂(质量比为45∶10∶5)为混合熔剂,碘化氨为脱模剂,熔融制备样片;采用经验系数法建立了SiO2、Al2O3、TFe2O3、MgO、CaO、Na2O、K2O、Ti、P和Mn共10个测量组分的标准曲线,各组分校正曲线的相关系数在0.9973~1.0000之间。对制样条件的实验优化结果表明,样品与熔剂比为1∶4,以2滴0.2 g/mL碘化氨为脱模剂,在1050℃熔融10 min,熔融制得的样片成型效果最好。对方法参数进行了研究,各组分相对标准偏差值在0.2%~5.3%之间,相对误差小于6.2%,方法精密度和方法准确度均较高。与常规称样量0.65 g熔片结果相比,两种方法实验结果一致。本研究为X射线荧光光谱法在地球化学标准物质均匀性检验中的应用提供了依据。
X ray fluorescence spectrometry(XRF)is one of the important methods to test the homogeneity of geochemical reference materials,but there is still controversy about the application.The homogeneity test requires the prerequisite that the sample weight is the minimum.The result of homogeneity test using conventional powder tableting or melting samples by XRF is generally larger than the minimum sample weight,so the results obtained are not theoretically sufficient to support the homogeneity of the sample under the condition of minimum sample weight.In this study,the 0.1 g samples experienced melted preparation with a mixed flux of Li2B4O7 LiBO2 and LiF(mass ratio 45∶10∶5)and NH4I release agent.The authors established an experiential method to analyzetotally 10 measuring components,i.e.,SiO2,Al2O3,TFe2O3,MgO,CaO,Na2O,K2O,Mn,Ti and P.The correlation coefficient of the calibration curve of each component was between 0.9973 and 1.0000.The experimental optimization results of sample preparation conditions showed that the ratio of sample to mixed flux was 1∶4,2 drops of 0.2 g/mL and ammonia iodide were used as the mold release agent,melting at 1050℃for 10 min.,leading to the best molding effect.The method parameters were studied.The relative standard deviation of each component was 0.2%~5.3%,and the relative error was less than 6.2%.The method precision and method accuracy were high.Compared with the conventional sample weighing of 0.65 g,the experimental results of the two methods are consistent.This study provides the basis for the application of X ray fluorescence spectroscopy to the homogeneity test of geochemical reference materials.
作者
赵红坤
郝亚波
田有国
高祥照
刘亚轩
ZHAO Hong-Kun;HAO Ya-Bo;TIAN You-Guo;GAO Xiang-Zhao;LIU Ya-Xuan(Institute of Geophysical and Geochemical Exploration,Chinese Academy of Geological Sciences,Langfang 065000,China;China University of Geosciences,Beijing 100083,China;TJ-Standard(tianjin)Metrology Testing Co.Ltd,Tianjin 300380,China;National Agro-Tech Extension and Service Center,Beijing 100026,China)
出处
《物探与化探》
CAS
北大核心
2020年第4期778-783,共6页
Geophysical and Geochemical Exploration
基金
“全国土壤污染状况详查”国家专项二级项目“土壤详查统一监控样品研制”。
关键词
熔融制样
X射线荧光光谱法
小取样量
主量元素
fusion preparation sample
X ray fluorescence spectrometry
small sample quantity
major elements
