Design and Construction of the DEMS Instrument

  • Sean James Ashton
Part of the Springer Theses book series (Springer Theses, volume 8)


In this chapter, details of the DEMS instrument design and construction created as part of this thesis are presented. The instrument employs a dual thin-layer electrochemical flow cell and microporous PTFE membrane interfaced to a high vacuum system containing a QMS. The vacuum system design possesses a tubular aperture to control and direct the flux of gas through the cross-beam ion source, whilst a 3-stage differentially pumped vacuum construction provided optimum operating pressures of the QMS in order to maximise instrument sensitivity.


Vacuum System Vacuum Pressure Membrane Interface Virtual Instrument Graphical Code 
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Copyright information

© Springer-Verlag Berlin Heidelberg 2012

Authors and Affiliations

  • Sean James Ashton
    • 1
  1. 1.Department of ChemistryUniversity of CopenhagenCopenhagenDenmark

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