Abstract (EN):
The shape of a differential thermal analysis (DTA) curve depends on the sample and the reference, the heating or cooling rates used in the
experiment as also the thermal resistance to heat ¯ow from the heat source to the cell containing the sample (or the reference), Ra (Rr).
Having access to a database that contains the values of the sample heat capacity, Cp, and those of the enthalpy of transformation, H, and
calculating the parameters that depend on the apparatus, the cells and the reference, as well as the heating rate used, it is possible to
determine the T (Ta ÿ Tr) values through the equation
Ta ÿ Tr ˆ Ra
dH
dt
‡ RrCr
dTr
dt ÿ RaCa
dTa
dt
where Ca is the heat capacity of the cell ‡ sample system and Cb the heat capacity of the cell ‡ reference system. The comparison between
the calculated and experimental values for T enables an assessment to be made as to whether the modelled parameters are in agreement
with the experimental information. This procedure enables a deeper perception of the thermal analysis in general and of the apparatus used
in particular.
Language:
English
Type (Professor's evaluation):
Scientific
No. of pages:
3
License type: