Why Does My DSC Baseline Go Below Zero?

Thread starter jaejoon89
Start date Dec 14, 2009
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The discussion centers on the issue of a Differential Scanning Calorimeter (DSC) displaying baseline values below zero (negative values). Key points include the possibility of bad calibration affecting the readings, as the absolute number is less significant than the relative change from the initial value set. Another consideration is the potential conversion between polymorphs, which could release energy and result in negative values. Participants also suggest verifying the consistency of results by running the same sample multiple times to see if the negative values persist.

Dec 14, 2009

jaejoon89

My baseline for the DSC goes past zero (below 0 W/g) why would the instrument be doing this?

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Dec 14, 2009

alxm

Science Advisor

This may be obvious, but: Bad calibration?

Dec 14, 2009

wangasu

it goes relative to the initial value you put in. the absolute number does not mean much.

Dec 18, 2009

chemisttree

Science Advisor

Homework Helper

Gold Member

Perhaps you converted from one polymorph to another and a little energy was released? Have you run the same sample twice and noticed the negative value again?

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