Differential scanning calorimetry running conditions

Figure 2 Differential scanning calorimetry results (cooling) for a sample of runny cream and thick cream. Run conditions sample mass 13.0 mg, cooling rate 10°C/min, sealed aluminum pans.

Acidity modification of the external surface was characterized by differential scanning calorimetry (DSC) after pre-adsorption of 4-methyl quinoline which cannot enter the pore system. For comparison, sample OW-ZSM-5 and sample lOW-ZSM-5 were subjected to DSC measurements without amine pre-adsorption. In each case, after completion of the first DSC run and re-establishment of initial conditions a second run was performed, and the resulting profile was substracted from that of the first run. In this way, device-dependent factors are eliminated. Measurements were performed by means of a SETARAM DSC-92 equipment under 3 1/h air and nitrogen, respectively, and a heating rate of 5 K/min. 

Ignition temperatures determined by differential scanning calorimetry (DSC) usually correspond reasonably well to those obtained by a Henkin-McGill study. DSC values tend to be more reproducible from laboratory to laboratory, and from sample to sample. Differences in heating rate, sample size, homogeneity, etc., can cause some variation in values obtained with thermal analysis technique. For any direct comparison of ignition temperatures, it is best to run all of the mixtures of interest under identical experimental conditions, thereby minimizing the number of variables. 

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