ICP-MS离子提取模型的建立与传输透镜的参数优化

Ion Extraction Model and Parameter Optimization of Transmission Lens in Inductively Coupled Plasma Mass Spectrometer

电感耦合等离子体质谱(ICP-MS)具有对一种或多种基本元素、同位素快速分析的能力,在诸多领域有其广泛应用。本文对ICP-MS接口部分中等离子体气流及离子的运动过程进行了理论分析,基于Child鞘层定律首次建立了正离子提取模型,以确定离子束形成的初始位置。然后在忽略空间电荷效应的前提下,利用电、离子光学模拟软件SIMION计算离子在透镜传输系统中的运动轨迹,通过调整透镜电极电压参数来获取最佳的离子传输效率,并以此作为分析实验前透镜调谐工作的理论依据。

The motion of the plasma flow and the positive ions at the extraction interface in the ion transmission sys- tem of the inductively coupled plasma mass spectrometer （ICP-MS）, was theoretically studied. First, the positive ion ex- traction was modeled, on the basis of Child law, and evaluated for the purpose of determining the initial position of the ion flow. Next, the ion trajectories in the transmission system were simulated with the software package SIMION, excluding the influence of the space charge. Finally, the ion transport efficiency was optimized by adjusting the lens potentials. We sug- gest that the simulated results may be of some basic and technological interest in design optimization of the vacuum inter- face and the ion transmission system.