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DSC standard for Indium with higher enthalpy values than normal

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kombito:
Hello, i work with thermal analysis (DSC and TGA) and my standard for indium is, usually, around 6.9 mg, with the values for its enthalpy ranging from 28 to 31 J/g. However, currently the value is within the range of 50 to 55 J/g since a few days ago, and i've looked everywhere to search a cause for it, but i just can't find any good reason for it.

The chamber haven't been cleaned recently for this to be a reason, nor any analysis that may present a risk for it. May this be a big problem for it to be necessary giving a call to a specialized technician? Can this affect negatively ou substancially future analysis?

The last three exact readings for it are:
1 - Mass - 8.1 mg; Temp - 156.83ºC; Enthalpy - 53.514 J/g
2 - Mass - 6.9 mg; Temp - 156.94ºC; Enthalpy - 51.358 J/g
3 - Mass - 6.9 mg; Temp - 156,75ºC; Enthalpy - 50,810 J/g

Thanks in advance

mjc123:
Has the calibration been reset recently (deliberately or accidentally)? The machine should have a calibration log.

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