TA Instruments TMA 2940 CE, Руководство оператора, Страница: 86 / 178

Running Experiments
TA I
NSTRUMENTS
TMA 2940 CE 3–22
Subambient
Experiments
The TMA can be used to run experiments on
cooled samples with a cooling source such as
liquid nitrogen. In order to perform subambient
experiments, the furnace must work against the
coolant in the reservoir. Ideally, you should use
the least amount of coolant necessary to keep
the furnace drawing power over the entire
subambient range.
If the “Return to temperature range” method-
end condition is activated, press the STOP key
to deactivate it before trying to cool the TMA.
Performing a
Cooling Experiment
To run a subambient experiment, perform the
same operations as described in "Running a
TMA Experiment" on pages 3-10 to 3-21. Once
the sample is loaded and the furnace is lowered,
conduct the following operations:
1. Turn on the purge gas at 100 mL/min, and
allow it to flow for 3 to 5 minutes to ensure a
moisture-free environment.
2. Pour coolant carefully into the top of the
furnace, refilling it as needed in order to cool
the sample below the desired temperature.
NOTE: