Creating A Method - Agilent Technologies 7500 ICP-MS Operator's Manual

Agilent 7500 ICP-MS ChemStation Operator's Manual

Creating a Method

Creating a Method
A method encompasses data acquisition and data analysis. Use them to define
parameters for acquiring and analyzing data.
The last method used before closing ChemStation is loaded into memory, next time
you access the software. The three most recently loaded methods are listed as
numbered menu items, with the first entry corresponding to the most recently loaded
method. Selecting any one of these numbered menu items will cause that method to
be loaded. The name of the current method is displayed in the title bar at the top of
the window. You can create a new method by editing any existing method and
saving the changes to disk under a new name.
This chapter explains how to create a method. There are four types of acquisition
modes for which you can create a method:
• Spectrum acquisition accumulates a signal for the entire data acquisition period,
100 scans. The signal displays as an accumulated intensity versus mass plot (mass
spectrum) for the masses previously selected in the method. You can acquire both
qualitative and quantitative data using Spectrum acquisition.
• Time Resolved Analysis acquisition (TRA) produces a transient signal that
appears as an intensity versus time plot (time chart). This acquisition mode is
usually used when the signal changes with time. You can monitor and display the
signals obtained for each selected mass, in real time. It is useful for applications
which use the Agilent 7500 combined with peripheral equipment such as the
Liquid Chromatography, Laser Ablation System, etc.
• Time Program acquisition is basically the same as TRA but more powerful. You
can change tuning parameters and the analyte mass automatically during TRA
acquisition, allowing complex chromatographic programs to be developed.
• Isotope Analysis is similar to Spectrum analysis, but the number of scan is 1000.
This allows for better precision when determining isotope ratios, for example in
geological studies.
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