Thermo Finnigan LCQ Deca XP Plus, Руководство по оборудованию

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Functional Description
API Source _________________________________________________________________
1-8
____________________ LCQ Deca XP Plus Hardware Manual ________________
APCI Probe Assembly
The APCI probe assembly consists of the APCI flange, the APCI slide
assembly, the APCI probe, and the corona discharge needle assembly. See
Figure 1-4, Figure 1-5, and Figure 1-6.
The APCI flange holds the APCI slide assembly. The APCI slide assembly
holds the APCI probe in position near the entrance to the ion transfer
capillary. The APCI flange also holds the corona discharge needle assembly.
As with the ESI flange, the APCI flange seals the atmospheric pressure region
(also called the spray chamber) of the API source. Two flange retainer bolts
hold the APCI flange in place against the spray shield of the API stack. When
the APCI flange is in the operating position against the spray shield, it
compresses the high-voltage safety-interlock switch. The APCI flange mounts
on rails that allow movement of the flange into and out of the spray chamber
for easy servicing.
The APCI slide assembly allows the probe to move parallel to the axis of the
ion transfer capillary, or orthogonal to the axis of the ion transfer capillary. A
probe retainer bolt can be used to secure the APCI probe to the slide of the
APCI slide assembly, and prevent movement of the probe orthogonal to the
axis of the ion transfer capillary. Even when the probe retainer bolt is in use
for this purpose, the probe can be moved parallel to the axis of the ion transfer
capillary.
The APCI probe accommodates liquid flows of 100
µ
L/min to 2 mL/min and
ionizes the sample by atmospheric pressure chemical ionization. The APCI
probe includes the APCI sample tube, nozzle, manifold, sheath gas plumbing,
auxiliary gas plumbing, and vaporizer. The axis of the APCI probe is
orthogonal to the axis of the ion transfer capillary. See Figure 1-6. The
difference in electrical potential between the ions and the ion transfer
capillary causes the ions to travel along a curved path to reach the entrance to
the ion transfer capillary. The geometric arrangement of the APCI probe and
the API stack helps keep the ion transfer capillary clean.
Sample and solvent enter the APCI nozzle through the sample tube. The
sample tube is a short section of 0.15 mm ID fused silica tubing that extends
from the sample inlet to 1 mm past the end of the nozzle. The manifold
houses the APCI nozzle, the sheath gas plumbing, and the auxiliary gas
plumbing. The sheath gas plumbing delivers dry nitrogen gas to the nozzle.
The auxiliary gas plumbing also delivers dry nitrogen gas to the nozzle.