TSI Incorporated 3480, Руководство пользователя

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4–8 Model 3480 Electrospray Aerosol Generator
C h a n g i n g S a m p l e s
Caution must be used when changing samples to avoid
contaminating either of the samples. A buffer solution should be
run in the Electrospray between samples to clear the capillary of
possible contaminants. Follow the procedure below (see “
Starting
Up the Electrospray ” earlier in this chapter for details) to change
samples.
!
C a u t i o n
To avoid contaminating samples, a buffer solution should be run between
samples to clear the capillary of possible contaminants.
1. Remove the bottom half of the pressure chamber.
2. Close the lid of the vial and remove it.
3. Insert a vial containing buffer solution.
4. Replace the bottom half of the pressure chamber.
5. Run buffer solution for one minute.
Note : The residence time in a capillary using a standard buffer
solution at 3.7 psi is approximately 112 seconds. For most
applications, running a buffer solution for 60 seconds will
sufficiently prevent sample contamination; however, using a
highly viscous fluid or a low capillary pressure drop will
increase the residence time. See Appendix B, “
Theory of
Operation ” for an analysis of liquid flow in the capillary.
6. Repeat steps 1–4, using a sample vial rather than a buffer
solution.
7. Aerosol should be produced after a time equal to the residence
time of the particular sample and operating conditions.
S h u t t i n g D o w n t h e E l e c t r o s p r a y
The capillary should be cleaned and cleared of liquid before
shutting down the Electrospray to avoid deposits on the inside of
the capillary. Follow the procedure below (see “
Starting Up the
Electrospray ” for details) to shut down the Electrospray.