Varian 4000 GCMS, Installation Procedures Manual

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6.4 BZP Acquisition
Use the Inject Single Sample option to make a 1µL manual injection of test mix
03-931126-01. Use a lower air gap to avoid sample loss through the tip of the
needle. Ensure the syringe plunger is not forced out of the syringe barrel if a
Pressure Pulse is used in the method. Inject slowly (1µL/sec.) to avoid sample
loss through explosive vaporization. Ensure the split valve has changed from
opened to closed before injecting by striking the injector auto-start switch with the
syringe barrel before depressing the syringe plunger.
6.5 Signal-to-noise Calculation
Use the quick load option shown in Figure 5.2 to load the BZP data file into
MSDR. Plot a single ion chromatogram of the m/z 183 ion. Refer to Figures 5.3
and 5.4 but be sure to plot ion m/z 183. Click the apex scan to display the
spectrum. Refer to Figures 5.10 and 5.11 and background correct the spectrum.
Right mouse click the apex scan and select Calculate Noise (refer to Figure 5.5).
The RMS signal-to-noise calculation will be performed for the scan closest to
where the cursor was placed for the right mouse click. Use 5 Point Savisky Golay
smoothing. A passing signal-to-noise calculation is shown in Figure 6.4.
Figure 6.4