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automatically open and the platinumware holders will be slid outside. The user
then manually adds the desired amount of non-wetting agent directly into the hot
crucibles, and then presses Start to resume the normal fusion.
While this feature can be useful with extremely sticky samples, one must keep in
mind that the quantity of non-wetting agent injected manually may not be exactly
the same for each crucible, and thus could lead to analytical issues.
Pouring step
The pouring step is when the crucible is tilted forward quickly, to empty its
contents either into a mold or a beaker containing acid. However, pouring can be
turned off altogether, for those fusion types where pouring is not desired: fusions
in sodium peroxide or potassium pyrosulfate.
Basic pouring parameters
well. Adjustment is sometimes required to adapt to melt viscosity and mold size.
Annealing
Generally, however, cracking and crystallizing disk problems can be cured by
proper control of the cooling (see below).
Crucible shaking
wishes to completely transfer the melt out of the crucible. This is mostly done with
the help of non-wetting agent, but can also be helped with a mechanical shaking
of the crucible after pouring.
The shaking feature is activated by setting the number of shaking motions (1x to
25x) and the shaking amplitude (1° to 20°). Press the right half of the button to
increase the parameter, or the left half to decrease. Setting those parameters to
zero will cause no shaking.
Pouring can be completely turned off
and on by pressing the red and green
vertical switch.
If pouring is on, the crucible tilting
angle and speed can be controlled with
the plus and minus buttons.
Generally, a pouring angle of 120°
with a speed of more than 30% works
Annealing is very rarely used, except in very
specific applications, with highly unstable
glass disks (i.e. disks that always crack or
crystallize). When activated (by means of the
horizontal
red
and
instrument will pull the full molds (after the
pouring) back into the furnace, at the given
temperature,
for
the
(adjustable with the plus and minus buttons).
In some cases, a droplet will remain stuck
inside the crucible. Once cooled, it can easily be
pinged off. However, in some instances, one
green
switch),
the
given
duration
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