User`s guide

Theory of Thermal Desorption
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or decrease the carrier-gas pressure during trap desorption to
improve desorption efficiency and give better recoveries and
peak shapes.
• Method sequencing allows the use of different flows and
pressures in methods to enable different analyses to be
performed in the same run and also to simplify method
development and optimization.
• MS mode ensures that internal valving and pneumatics are
continually swept with a low flow of carrier gas to minimize
build-up of air, water and organic contaminants that would
otherwise interfere with analyses (especially with a mass
spectrometer detector).
• Automatic reduction of gas flows when system is idle
delivers cost savings by ensuring gas conservation once an
analysis is complete.
Figure 85 PPC Configuration