一种变形标准加入法及其在等离子体发射光谱分析中的应用

发布时间：2018-03-24 22:07

本文选题：标准加入法　切入点：背景校正　出处：《光谱学与光谱分析》2017年11期

【摘要】：在小体积(50μL)液体取样时,容易产生较大的取样误差,为了降低分析结果的不确定度,常常用质量定量法代替体积定量法。传统标准加入法以样品体积定量,不能用于以样品质量定量的场合。为此,我们提出了一种变形标准加入法,以便用于以样品质量定量的场合。以ICP-OES法测定复杂溶液体系中低含量及微量元素Hg,Mo和Rh为例,对变形标准加入法进行了介绍。标准加入法的目的是为了校正溶液基体效应,而溶液基体效应包括两种不同类型的干扰:"恒定干扰"和"比例干扰"。变形标准加入法只能校正溶液基体效应中的"比例干扰","比例干扰"的大小可以用一个定量指标k表示:当k=1时,表示不存在"比例干扰"的影响;k偏离1越远,则"比例干扰"的影响越大。至于"恒定干扰"的影响,则可以利用仪器自身的背景校正方法予以降低或消除。变形标准加入法测定结果不确定度主要来自于背景校正,与所选分析线的信背比密切相关。信背比越低,背景校正的不确定度越高,因此实际分析中应尽可能选择具有较高信背比的分析线,否则,即使事先经过了背景校正,最终的分析结果也可能包含很大的误差。
[Abstract]:In order to reduce the uncertainty of analysis results, the mass quantitative method is often used instead of the volume quantitative method, and the traditional standard addition method is used to quantify the volume of the sample, in order to reduce the uncertainty of the analysis results, it is easy to produce a large sampling error when the sample is sampled in a small volume of 50 渭 L liquid. This paper presents a deformation standard addition method for quantitative determination of low content and trace elements Hgomo and Rh in complex solution system by ICP-OES method. The deformation standard addition method is introduced. The purpose of the standard addition method is to correct the solution matrix effect. The solution matrix effect includes two different types of interference: "constant interference" and "proportional interference". The deformation standard addition method can only correct the "proportional interference" in the solution matrix effect, and the size of the "proportional interference" can be determined by a single method. The quantity index k is expressed as: when k = 1, The greater the deviation from 1, the greater the effect of "proportional interference." as for the effect of "constant interference," The uncertainty of the result of the deformation standard addition method mainly comes from the background correction, which is closely related to the signal-back ratio of the selected analysis line, and the lower the signal-back ratio, the lower the signal-back ratio. Because the uncertainty of background correction is higher, the analysis line with high signal-to-back ratio should be chosen as much as possible in practical analysis. Otherwise, even after background correction, the final analysis result may contain a lot of errors.
【作者单位】：清华大学核能与新能源技术研究院先进核能技术协同创新中心;中核四○四有限公司第二分公司;
【基金】：国家自然科学基金项目(21271113)资助
【分类号】：O657.31

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