attension Theta, User Manual

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Figure 3.19. Air-liquid surface tension measurement by pendant drop method.
Figure 3.20. Liquid-liquid interfacial tension measurement by pendant drop method.
Meniscus experiments
The fibers commonly used with Meniscus experiments are very thin, and so often requires the use of the
zoom lens and additional lighting for the zoom lens. Before beginning the measurement, clean the solid
appropriately and attach it to the syringe clamp.
Theta instrument can be used to investigate cylindrical shapes such as rods or fibers as well as shapes
that are not symmetrical about their axis such as plates. For the sake of convenience for the rest of this
section of the manual the solid sample will be referred to as a rod, but keep in mind that plates, fibres,
etc. can also be used.
Adjust the position of the rod until it is visible on the image. Lift the liquid or lower the rod until the two
surfaces intersect and a meniscus is formed. If necessary use a trigger, in most cases it should be
sufficient to manually press Start/ Record once the meniscus is visible.