论文部分内容阅读
热表面电离质谱计(TIMS)MAT261在采用二次电子倍增器(SEM)接收时,SEM积分模拟模式的测量存在质量歧视效应和强度歧视效应。本研究测量了其质量歧视校正因子,建立了强度歧视效应基本可以忽略的测量方法。为实现弱信号的准确测量,建立SEM离子计数测量模式。基于SEM离子计数测量技术,应用钚标样比较SEM积分模拟模式测量和离子计数模式测量的结果。在控制离子流强度的条件下,两种方法的测量结果与标样标称值在不确定度范围内符合。
Thermal Surface Ionization Mass Spectrometry (TIMS) MAT261 Mass absorption and intensity discrimination effects exist in the measurement of SEM integral simulation mode when it is received using a double electron multiplier (SEM). This study measured the quality of the discrimination correction factor, the establishment of a discriminatory effect of the intensity of the basic negligible measurement methods. In order to achieve the accurate measurement of weak signal, the establishment of SEM ion counting measurement mode. Based on the SEM ion counting measurement technique, the plutonium standard was used to compare the SEM integral simulation mode and ion counting mode measurement results. Under the condition of controlling the ion current intensity, the measurement results of the two methods are in accordance with the nominal value of the standard within the range of the uncertainty.