The Nature of Mobility Data

So far in this discussion the emphasis has been on assigning a feature in an ion mobility spectrum to the products of a specific ion—molecule reaction. However, there are other ways of using the information contained within a mobility spectrum.

It is possible to study gas-phase reactions and ion—molecule processes within the drift tube with a tuned mass spectrometer. Thus, equilibrium constants for clustering reactions, activation energies for ion—molecule reactants and molecular sizes have all been determined with IMS. The introduction of dopant to the drift region of the instrument enables the reaction kinetics of ion—molecule reactions to be studied and data derived so far from such studies have agreed closely with accepted literature values.

IMS data can also be used in a completely phenom-enological-based manner. Complex but constant mixtures yield reproducible ion mobility spectra, although the interpretation and assignment of individual features in such spectra is not currently possible. The application of pattern recognition algorithms and standard chemometric tools enables IMS to be used to identify changes in composition or types of sample. So far identification of different types of polymers, wood species, foodstuffs and pharmaceutical products has been demonstrated. This is an application area that undoubtedly has significant commercial potential.

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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