Malvern Zetasizer Nano Series, Руководство пользователя

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Size ranges and measurement thresholds can be applied to the analysis to filter
spurious peaks prior to the analysis being performed.
Please see the Advice button for more information.
+ General Purpose
Select this model for most cases, especially if the sample to be measured is
unknown. The result will reveal details about the number of modes and the shape
of the zeta potential distribution.
To obtain a detailed measurement a minimum of 10 runs should be performed. If
the sample is thought to generate a multi-modal distribution then 20 to 30
measurement runs should be performed.
, Monomodal
The monomodal model should be used if only the zeta potential mean value is
required. In this case only 5 to 10 runs are required to obtained a detailed
measurement.
This mode is recommended for time, pH and temperature trend measurements
as well for samples known to have a conductivity greater than 5milliSiemans.
- Advanced
The Advanced button dialogue enables both the measured Zeta potential
range and the measurement thresholds to be set.
If it known that all particles within the sample will fall within a certain Zeta
potential range, then the
Zeta range can be set to improve repeatability of the
measurement result; similarly a lower threshold can be applied to eliminate
undesired particles that are below a defined percentage of the particle population.
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N o t e
. If the Zeta range or Threshold values are different from the default
settings the Advanced button will be shown with a red exclamation
mark . Moving the cursor over the button will display the message
“ Advance settings not at default ”.
Using the Smoothing function, it is possible control the sharpness and shape of
the plotted zeta potential distribution, i.e. with an increased smoothing figure,
two distinct peaks will begin to blend together to show a gentler distribution.
Please see the Advice button for more information.
C H A P T E R 9
Z e t a s i z e r N a n o S e r i e s
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