Differential scanning calorimeters enthalpy calibration

The heat flux and energy calibrations are usually performed using electrically generated heat or reference substances with well-established heat capacities (in the case of k ) or enthalpies of phase transition (in the case of kg). Because kd, and kg are complex and generally unknown functions of various parameters, such as the heating rate, the calibration experiment should be as similar as possible to the main experiment. Very detailed recommendations for a correct calibration of differential scanning calorimeters in terms of heat flow and energy have been published in the literature [254,258-260,269]. 

Example Determination of the Heat of Fusion by Means of DSC Let us assume that the task is to determine the heat of fusion of an unknown sample by means of differential scanning calorimetry. The calorimeter is first calibrated by using a certified sample of indium of mass mdb = 10.12 mg as the calibration material. The certificate states an enthalpy of fusion of Afush<-ib = (28.64 0.06) Jg. Four measurements are performed and give the following results (peak areas 2 <-ii,) 284.15, 281.39, 263.49, and 276.04m). The mean value is Adb = 276.27 mj. The calibration factor Kq of the instrument is calculated according to the following equation ... 

---