Gating the Ions into the Drift Tube

This feature provides IMS with a time-resolved response as opposed to a change in a standing current. An ion shutter is pulsed open for, typically, c. 0.2 ms every 5—40 ms, depending on the experimental conditions. The duration that the gate is open is important, as the longer it is open the larger the response (more ions get through) but the broader the ion peaks (greater temporal distribution of identical ions), and hence the lower the resolution will be.

A most important advance has been control of the electric field at the point between the reaction and drift regions with an ion trap. This allows the accumulation of ions between injection pulses rather than their annihilation, with significantly increased sensitivity and much greater control of the ionization processes used to produce the mobility spectra (see Figure 5).

Solar Panel Basics

Solar Panel Basics

Global warming is a huge problem which will significantly affect every country in the world. Many people all over the world are trying to do whatever they can to help combat the effects of global warming. One of the ways that people can fight global warming is to reduce their dependence on non-renewable energy sources like oil and petroleum based products.

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