电感耦合等离子体质谱仪中氩原子和钙离子的动力学温度及终端移动速率测量  

Measurement of kinetic temperature and terminal velocity for argon atom and calcium ion in inductively coupled plasma mass spectrometry

作　　者：马海斌[1] 孙自杰[2] 

机构地区：[1]潍坊学院化学化工与环境工程学院,山东潍坊261061 [2]环境保护部标准样品研究所,北京100029

出　　处：《冶金分析》2015年第8期7-11,共5页Metallurgical Analysis

基　　金：2012年度国家环境保护标准制修订项目(2012-60)

摘　　要：为保证电感耦合等离子体质谱仪(ICP-MS)的最佳检测性能,不同分析离子应连续一致的高效通过取样界面,而理解离子在取样界面的非理想传递行为至关重要。基于多普勒频移及高分辨率激光诱导荧光技术,建立了ICP-MS取样锥后不同粒子的动力学温度及终端移动速率测量装置,并在定义水平与竖直方向上钙离子的最大荧光响应交叉点为校直零点的基础上,计算比较了氩原子及钙离子终端移动速率及动力学温度变化,结果表明在等离子体炬管竖直及水平方向上扫描钙离子终端移动速率比中性氩原子快,说明在取样锥后带电粒子被加速,发生了双极电场扩散现象及带电粒子加速运动,使带电离子更偏离等离子体中心轴向,并更难以到达截取锥口。实验结果可为取样界面传递效率计算及相关模拟模型发展提供实验数据支持。In order to guarantee the optimal detection property of inductively coupled plasma mass spectrometry(ICP-MS),the different analytical ions should pass the sampling interface efficiently and continuously.Therefore,the understanding of non-ideal transfer behaviors of ions on the sampling interface was very important.The measurement equipment of kinetic temperature and terminal velocity of various particles after the sampling cone of ICP-MS was established based on the Doppler frequency shift and high resolution laser induced fluorescence technologies.It was defined that the maximum fluorescence response intersection of calcium ion between horizontal and vertical directions was the zero point of calibration.The changes of terminal velocity and kinetic temperature of argon atom and calcium ion were calculated and compared.The results showed that the terminal velocity of calcium ion on vertical and horizontal directions of plasma torch tube was higher than that of neutral argon atom,indicating the acceleration of charged particle after sampling cone.The ambipolar diffusion in electric field and the acceleration of charged particles resulted in the more deviation from center axis of plasma.Therefore,it was more difficult to reach the skimmer cone.The experimental results could provide data support for the calculation of transmission efficiency on sampling interface and the development of related simulation model.

关 键 词：电感耦合等离子体质谱 取样锥 双极扩散 超声膨胀 

分 类 号：TH843[机械工程—仪器科学与技术] O657[机械工程—精密仪器及机械]