is not necessary to fill the table. When all the data is entered, click
Calculate
. The main peak heights will be calculated and a graph of
concentration vs. peak height is plotted. A line of best fit will be drawn
through the data points and the y-intercept shown which corresponds to the
unknown sample concentration for the metal of interest. The value shown is
a negative because this indicates the amount which needs to be added to
each of the data points to ensure the line of best fit goes through the origin.
From the data entered into the example below, the unknown sample
concentration is 20.05ppb.
7. ADVANCED OPERATIONS
7.1 Background Subtraction
The
Background Subtraction
method is used to create a new baseline for
the analysis. Some of the buffers used may contain small amounts of
metals and the blank subtraction can be used to measure this and offset it
against the results. Performing this will replace the previous blank. The blank
offsets can also be cleared if required.
After each analysis the Sonde head and the electrodes should be washed
thoroughly. This is in order to minimise carry-over and to clean off all traces of
the previous analysis. The Sonde head can be washed in the sample water
and then given a final rinse with the rinse solution in the kit.
Metalyser® Field Pro HM3000 Instruction Manual v 5.0
www.trace2o.com
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