PerkinElmer AVIO 500, Руководство по оборудованию и обслуживанию для клиентов

Страница: 321 / 355

319
Sodium Bullet Test
• Precision Test: This test indicates the Relative Standard Deviation (RSD) of
the instrument's analyte emission intensity or concentration measurements.
The RSD may also be referred to as the CV (Coefficient of Variation). A high
RSD or CV is usually indicative of a problem with the sample introduction
system such as improper drainage, leaks, improper tension on the pump tubing,
worn pump tubing, or nebulizer problems. Refer to the Syngistix Software
Guide on the Syngistix Document Pack CD for details .
• Detection Limit Test: This test measures the baseline signal for a blank
solution to give an indication of the lowest concentration of an element which
can be measured. The detection limit is calculated as three times the standard
deviation of the blank. Refer to the Syngistix Software Guide on the Syngistix
Document Pack CD for details .
Sodium Bullet Test
To run the sodium bullet test:
1. For aqueous analyses, aspirate a 1000 mg/L solution of sodium. For organic
analyses, aspirate an appropriate organic blank.
2. Examine the plasma through the viewing window in the sample compartment
door.
A yellow-orange bullet (or green, in the case of organic compounds) should be
visible in the center of the discharge, and should extend from the base of the
discharge to just below the top plasma induction plate. If the bullet height is
unsatisfactory, adjust the nebulizer argon flow in the Method Editor or Plasma
Control windows.
If no bullet appears or the bullet is faint:
• Check that your sample does contain sodium at the required concentration.
• Check that sample is being pumped to the nebulizer. Make sure that the pump
lever is engaged and that the pump tubes are connected appropriately.
• Check that the drain is being pumped properly. You should see a segmented
flow of bubbles through the tubing.