Agilent Technologies 7500 ICP-MS Operator's Manual page 156

Agilent 7500 ICP-MS ChemStation Operator's Manual
Tuning
4) Input the concentration of each mass number of the tuning solution in the Std
Conc Text Box and select the concentration unit in Conc Unit.
5) Select Std (standard solution) in Current Solution.
6) Select He Gas in the Ramp Flow group and input the minimum value,
maximum value, and the step size of the He gas flow rate to adjust the Flow
Rate.
7) Display the signals by clicking the Check Count button and confirm that the
signal is stable. At this time, the flow rate of He gas doesn't change. Click the
Stop button after confirming signal stability.
8) Click the Ramp Flow button. Sensitivity data is collected by changing the He
gas within the flow rate range that was previously set. A message will be
displayed on the message line after the data collection is complete.
9) When the previous step has finished, aspirate fresh DI water or nitric acid
solution (blank solution) whose concentration is the same as the tuning
solution.
10)Select Blank (blank solution) in the Current Solution.
11) Display the signal by clicking the Check Count button and confirm that the
signal is at a normal background level after replacing the solution. If it's not
low enough, wait until it falls. At this time, the flow rate of He gas doesn't
change. Click the Stop button after confirming an accepted background level.
12)Click the Ramp Flow button. The background data is collected by adjusting
the He gas within the flow rate range that was previously set. A message will
be displayed on the message line once the data collection is complete.
13)After collecting data from both the tuning and blank solutions, click the Graph
button to view the result.
14)The Reaction Gas Graph Dialog Box will appear. In the dialog box, the
sensitivity and BEC (Background Equivalent Concentration) of the tuning
solution and blank solution, for the different flow rates of He gas, are plotted
for each mass measured. Examine this graph and determine the best sensitivity
and flow rate of He gas while satisfying the BEC.
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