PerkinElmer Clarus SQ 8 MS Series, Руководство по оборудованию

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About the Clarus GC/MS System
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Ion Optics Path
Ion Source
The Clarus MS ion source consists of a removable ion source. The
Clarus SQ 8 C also supports a CI source. In the EI source, molecules
exit the column where they are bombarded by electrons from the
filament and ionized into positive and negative ions as well as neutral
species. The positive electron trap attracts the negative ions and
electrons to the repeller that directs the positive ions out of the inner
source through focusing lens to the mass analyzer. Those remaining
molecules and neutral fragments are pumped away by the vacuum.
Heaters in the outer source raise the source temperature high enough to
prevent sample molecules from condensing in the source and minimize
any contamination.
Mass Analyzer The mass analyzer element of this high performance quadrupole mass
spectrometer is a finely machined assembly that has been precisely
aligned using specialized equipment.
Under no circumstances should
the main analyzer rod set assembly ever be dismantled.
The mass spectrometer is fitted with a quadrupole prefilter assembly
that is designed to protect the main analyzer by intercepting the majority
of any contamination. As a consequence, the main analyzer should
never require cleaning.
On occasion, it may be necessary to remove the prefilter rods for
cleaning. The need to clean these rods is usually indicated by poor peak
shape or loss of resolution, although other more likely causes, such as
source contamination, should be eliminated first. It is necessary to
remove the inner and outer ion source assembly before the prefilter
assembly can be removed.
Detector The detector consists of a series of focusing lenses, a 270
⁰
turn and a
high voltage conversion dynode. The ions hit the high voltage
conversion dynode and are converted to electrons. The electrons are
directed into a series of diecrete dynodes with amplify the signal.
Finally the signal is collected and transferred to the Data system.
Electronics
The Clarus MS electronics consist of an Ethernet port in the PC, an
embedded processor & digital I/O board, analog board (GC/MS),
backplane board, head amplifier, and high voltage and low voltage
power supply modules. The embedded processor controls all aspects of
instrument and data acquisition.