分析系数法用于评价农业地质调查样品52个项目分析质量等级

A New Method of Evaluation for an Agricultural Geological Survey Sample of 52 Quality Graded Projects

土壤地球化学样品分析测试质量控制目前采用内部质量控制和外部质量控制相结合方法,重点从准确度、精密度、虚拟图等方面确保元素地球化学图成图质量,应用效果良好,不足之处是规范未规定统一的分析方法及评价分析质量等级的参数。分析系数是评价分析结果准确度和精密度的一个综合指标,既适用于实验室内部质量控制,又适用于实验室间质量控制,其评价方法简便易懂、量化直观,但在地矿实验室较少应用,有较好的推广应用价值。文章应用分析系数法评价河南省农业地质调查样品中4个日常监控土壤标准物质中52个项目的分析质量水平。依据多目标区域地球化学调查规范(1∶250000)相关指标计算出分析系数允许限,划分了质量评定等级并进行了实际应用。研究结果显示,4个土壤标准物质共208个分析项目中,其中138个项目达到优秀级,58个项目为良好级,12个项目为及格,总体分析质量好。对分析质量差的Se、Cr、I、Br、Th、C、Pb、Cd等8个项目,应查明原因,采取相应措施,提高这些项目分析的准确度和精密度。

Soil geochemical sample analysis quality control is currently used to combine intra-and inter-laboratory quality control.The accuracy,precision and virtual figures play key roles in geochemical drawing mapping quality with a good application effect.However,the deficiency is a lack of a unified analysis method and the evaluation parameters of the quality level.The analysis coefficient is the comprehensive proxy to evaluate analysis results for accuracy and precision,which is suitable for the laboratory internal quality control and for interlaboratory quality control.This assessment method is simple to understand with the direct-viewing quantification indexes.Since there are few applications in the geology and mining laboratory,it has a good promotion application value.The analysis coefficient method was first applied to evaluate the analysis quality level of agricultural geological survey samples in Henan Province consisting of 4 daily monitoring soil standard materials in 52 projects.The allowable limit of the analysis coefficient was achieved based on the related indexes of multi-target regional geochemical survey specifications（1∶250000）.The division of the level of quality evaluation was established with this practical application.4 soil standard materials with a total of 208 analysis projects were verified by this method,in which 138 items reached the outstanding level,58 projects were good,12 projects qualified,and the overall quality of the analysis was good.For the poor quality of Se,Cr,I,Br,Th,C,Pb and Cd projects,further work needs to be investigated further to improve the analysis accuracy and precision.