Fritsch ANALYSETTE 22 NeXT, Руководство по эксплуатации

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7. From this measuring results folder you can select an SOP by
clicking on "Measurement". By double clicking on it, the required
SOP is opened and can be processed again, if this was not for-
bidden when the SOP was created.
SOP refers to a Standard Operating Procedure
used in our software. In an SOP, work steps are
pre-defined and processed with a single key-
stroke.
Ensure that you select the SOP which is suitable
for your device.
8. Adjust the beam. Select the SOP "Laser Alignment Wet".
9. Click on "Start Measurement" to adjust the beam.
10. Once the beam is adjusted, select the SOP "Fritsch test powder
F500" in the measurement folder.
11. Click on "Start Measurement" to measure the Fritsch test powder.
12. A background measurement is carried out first.
13. Then during sample feeding you are asked to feed the sample to
the dispersion unit (see Ä Chapter 5.1.4 ‘Sample addition’
on page 30).
14. In the measuring results folder you can display the individual
measurements for the min. and max. curve of the Fritsch test
powder.
15. Once the measurement is finished, rinse out the measuring system
using the SOP "Clean / Fill".
6.1.2 Dispersion of barely wettable samples
Hydrophobic samples can be dispersed despite their water-repellent
properties, if they are first mixed to a paste with a liquid tenside (e.g.
Dusazin) and then dispersed by constant agitation.
Agglomerates are also dispersed more easily and faster in an external
ultrasonic cleaner, as the whole sample is constantly exposed to the
ultrasound. In the circuit of the dispersion unit, each particle of the
sample is only located briefly in the range of the ultrasound, because the
sample is constantly circulated.
In the case of soil samples, for example, a 0.1 - 0.5 % sodium pyrophos-
phate solution is recommended as a dispersing aid. The sample prepared
in this way in the external ultrasonic cleaner can be measured in pure
water.
Using the device
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