Theory And Principles Of Operation - Waters Micromass ZQ 2000 Operator's Manual

continuously measures vacuum pressure with a built-in Pirani gauge. The gauge also
serves as a switch, discontinuing detector operation when it senses vacuum loss.
A vacuum isolation valve isolates the source from the mass analyser, allowing routine
source maintenance without venting.
Mass Analyser (Quadrupole)
The mass analyser separates ions by mass-to-charge ratio (m/z).
Data System
The data system collects information from the mass analyser and includes these
components:
• MassLynx™ 4.0 software
• An external workstation
• An embedded PC
MassLynx software controls the workstation-based data system and mass detector
through the detector's embedded PC. Using MassLynx, you tune the instrument, set up
and run the HPLC system, and acquire and process data. When they are part of the
system, the software also controls the autosampler and the divert and injector valves.
The workstation uses a Windows NT
environment and allows full user interaction with the keyboard or mouse. A network link
communicates between the workstation and the detector's embedded PC.
MassLynx acquires and stores data from conventional LC detectors simultaneously with
data the mass detector acquires. It can also acquire data from selected systems, like
Waters 996/2996 Photodiode Array Detectors. Consult the MassLynx 4.0 Guide to Inlet
Control for details about MassLynx.

1.2 Theory and Principles of Operation

Electrospray Ionization (ESI)
In ESI, a high electrical voltage charges the eluent as it emerges from a nebulizer,
producing an aerosol of charged droplets. As the solvent evaporates, the droplets shrink,
developing a charge dense enough to eject ions from their surfaces (ion evaporation). The
mass analyser then sorts the singly or multiply charged ions by mass-to-charge m/z ratio.
The analyser source can accommodate eluent flows of up to 1 mL/min. You can enhance
performance by reducing the rate of eluent flow at the ion source.
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, Windows 2000, or Windows XP color graphical
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