As for TGA analysis, in order to get better result for the curve, it is recommended for us to subtract with the blank curve. So how about DSC?
Most of the DSC, analysis, no need to subtract anything. Directly, you obtain the results as exotherm or endotherm using the instrument software.
Dear Jasim Ahmed
Thank you for you feedback. True, normally for DSC no need to subtract anything. However, recently my supplier said normally need to subtract as same of TGA curve. That's why I ask in RG whether is there anyone did the same way for DSC curve.
As for TGA, at least it could discard for the increasing of weight especially for non-organic material. But for DSC, the curve will completely different if I subtract it with the blank sample. In my opinion, my supplier just gave me wrong information.
Dear Fareezex Mohd Rawi
The subtracting in DSC can be helpful if shape of your curve is not same as your supplier, for example when your curve is not slant, you can use subtracting. As I performed it in some of my previous works.
The subtracting can be performed easily by mathematical software, such as origin, and you needn't perform new test.
However, it should be noted that only the shape of curve would be changed, however, the temperature of transition remains intact.
Sincerely
M. Tayefi
Normally we don’t subtract as the reference is already a blank. However one can always cross check by running a blank. Blank should not give any peak. If it does calibration may be required. Again if the supplier insist on subtracting from blank then you may have to follow that to get better result.
As long as the instrument is well-calibrated (Both for heat-flow and heat-capacity) a separate blank subtraction is not needed. The working principle of the instrument is to do the subtraction automatically, to relieve us from having to run a blank separately. But in some extreme cases, if the heating and cooling baselines are not symmetric around zero (in heat flow space), a symmetry correction may be needed. But generally, this is only needed for some Fast Scanning Calorimetry (FSC) work.
If the empty pan measurement result in a not straight but very curved line in the respective temperature region it would be helpful to subtract it. Furthermore it is indeed nescesarry to subtract the empty pan line for heat capacity measurements.
I agree with Gunther. It is better to subtract the empty pan line, where the value stands by itself. Where the measurements are done on similar samples for comparison, it may not be required as the relative values are enough.
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