Now why would you be interested in a DSC on your Pointy Haired Boss?! (Sorry about this comment. In the states there is a very popular comic strip called "Dilbert", about a tech worker who is tormented by his PHB, an icon for all the incompetent managers in the world.
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But seriously, I'm not clear on what you are trying to do and what the exact problem is. The best I can tell is that you are heating the samples up (too hot if you are getting degradation) and then cooling them down to your desired temperture in order to...determine the crystallization rate at a fixed temperature? Is this correct?
Assuming that this is correct: From all of your problems, it almost seems as if you have an old unit that is in dire need of service or total replacement. I say this because the temperature measurement seems shot (it over heating the sample to the point of degradation) and you aren't running dry air in the oven (as seen by the condensation).
Can you check that the temperatures are accurate? (Heat a range of high purity samples with a well defined melting points). Can you run dry air or another dry gas in the oven (dry nitrogen could prevent degradation in the event of overheating) or maybe put the entire unit in a box with a drying agent?
If my assumptions are incorrect, please clarify them and I'll be glad to take another shot at your problems.
John Aspen Research, -
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"Turning Questions into Answers"
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