He L, Lubman D M
Department of Chemistry, University of Michigan, Ann Arbor 48109-1055, USA.
Rapid Commun Mass Spectrom. 1997;11(13):1467-77. doi: 10.1002/(SICI)1097-0231(19970830)11:13<1467::AID-RCM54>3.0.CO;2-X.
In this work we have developed a PC-based simulation to study ion injection, cooling and extraction processes for multiple ions in an trap/reflectron time-of-flight (IT/reTOF) system. This simulation is based upon SIMION 6.0 with user written programs in which a 3D collision model is used to describe ion--buffer gas molecule interactions. The results of various simulations describing the relation between the trapping efficiency for external injection of ions into the trap and the RF phase, and the effects of initial kinetic energy and ramp-up rate on dynamic trapping of externally produced ions are discussed. Further, single-pulsing and bipolar-pulsing schemes for ejecting ions from the trap are examined. The simulations show that bipolar pulsing can markedly improve the resolution. In the bipolar ejection mode the relation between resolution and the extraction voltages and RF ramp-off rate are studied.
在这项工作中，我们开发了一种基于个人计算机的模拟程序，用于研究阱式/反射式飞行时间（IT/reTOF）系统中多离子的注入、冷却和提取过程。该模拟基于SIMION 6.0，并配有用户编写的程序，其中使用三维碰撞模型来描述离子与缓冲气体分子之间的相互作用。讨论了各种模拟结果，这些结果描述了离子向阱外注入时的俘获效率与射频相位之间的关系，以及初始动能和上升速率对外部产生离子动态俘获的影响。此外，还研究了从阱中喷射离子的单脉冲和双脉冲方案。模拟结果表明，双脉冲可以显著提高分辨率。在双脉冲喷射模式下，研究了分辨率与提取电压和射频下降速率之间的关系。
