Traveling wave IMS. TWIMS

Conventional IMS is often called drift tube IMS (DTIMS) because the constant electric field is commonly established in tubes where ions drift along the axis. However, implementations of conventional IMS vary and other designs have emerged in both research and commercial systems. Some, such as traveling wave IMS (TWIMS), acmally employ a time-dependent field, but that is for instrumental reasons and does not affect the separation parameters. 

Recently, two other approaches to IMS have been introduced commercially these are high field asymmetric waveform IMS (FAIMS) [2] and traveling wave IMS (TWIMS) [3]. 

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