GE MOA 280i, Operation And Maintenance Manual

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GE Analytical Instruments ©2006
14-7
DLM 14291 Rev. A
Dynamic Headspace Analysis
The technique described above is often referred to as static headspace, since
the sample container is sealed, an equilibrium established between NO in the
gas and liquid phases and an aliquot of the gas sampled. In dynamic headspace,
the entire gas above the liquid is measured. A special container equipped with
a gas inlet and outlet is required for dynamic headspace. In this technique, NO
can either be continuously monitored or the sample allowed to equilibrate and
then the entire gas sample is injected into the NOA. For this technique, the
purge vessel is not used, instead the outlet of the apparatus is connected
directly to the gas sampling package of the NOA. A source of NO free gas is
connected to the container and is used to sweep the gas headspace from the
container into the NOA. Contact Sievers for more details and specific
references on dynamic headspace analysis.