Thermo Scientific TSQ Quantum XLS, Руководство пользователя

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Functional Description
Mass Spectrometer
34 TSQ Quantum XLS Series User Guide Thermo Scientific
Figure 24. Magnitude of the rf and dc voltages applied to the rods of the Q1 and Q3 mass
analyzers
Mass Analysis
The Q1 and Q3 rods are charged with a variable ratio of rf voltage and dc voltage ( Figure 24 ).
These potentials give rise to an electrostatic field that gives stable oscillations to ions with a
specific mass-to-charge ratio and unstable oscillations to all others.
At any given instant, one particular set of rf and dc voltage values is being applied to the mass
analyzer rods. Under these conditions, only ions of one mass-to-charge ratio (for example,
m/z 180) are maintained within bounded oscillations as their velocity carries them through
the mass analyzer. During this same time, all other ions undergo unbounded oscillations.
These ions strike one of the rod surfaces, become neutralized, and are pumped away, or they
are ejected from the rod assembly.
10,000 V P/P
840 V DC VOLTAGE