Beckman Coulter Multisizer 4, User Manual

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PN A51387A
B
4-17
Selecting Analysis Settings: SOM and SOP
Using a Standard Operating Method (SOM)
4
In the SOM Wizard, click
(
Next
)
to proceed to the next step.
Standard Operating Method: Concentration Information
Use Step 7 of the SOM Wizard (page 4-2 ) or the Concentration tab of the Edit the SOM window
(page 4-23 ) to enter information about sample volume, density, and dilution.
NOTE
For particle concentration analyses, use volumetric mode. For size distribution analyses, use any
available control mode.
1. In the Sample Amount pane:
• Select Volume if you are entering the volume of a sample suspended in liquid. Enter the
volume of liquid sample in the mL field.
• Select Mass if you are entering the mass of a dry sample of particles. Enter the density of
the dry sample in the Density field (available in a chemical handbook).
2. Select Use Pre-dilution Factor if you are diluting your sample (for example, if you are adding
electrolyte to a dry sample) before you add the sample to the electrolyte solution in the beaker.
Enter the ratio of electrolyte solution to sample (the pre-dilution factor).
If you select Use Pre-dilution Factor, the software will not allow you to enter a dilution factor.
The only possible combination is Pre-dilution factor (ratio of electrolyte solution to sample)
added to electrolyte solution volume.
3. In the Analytic Volume text field, enter the volume of electrolyte solution and sample that will
pass through the aperture during the run.
To enter an accurate value in the Analytic Volume field, it is necessary to run your analysis in
volumetric mode. If it is not possible to use volumetric mode (for example, if your aperture is
larger than 360 µm) you can estimate the analytic volume. To estimate analytic volume, run a
timed analysis several times and average the volume of sample that passes through the orifice.