D.T.A. - differential thermal analysis

Figure 9. Thermal analysis of levoglucosenone samples (a) neat, (b) +5% zinc chloride, (c) +5% diammonium phosphate, and (d) +5% diphenyl phosphate (D.t.a., differential thermal analysis T.g., thermo gravimetry D.t.g., derivative of thermogravimetry)...

Keywords D.T.A.-Differential Thermal analysis magnetic susceptibility, Mossbauer... 

The technique of differential thermal analysis (D.T.A.) has been applied to the study of the systems CraOa, FeaOs, and CrjOa-FejOj. 

The technique of differential thermal analysis (D.T.A.) has been extensively employed in the study of clay and other minerals for elucidating their structures for more than three decades. The application of D.T.A. as a tool has not been widely made to the systematic study of solid catalysts. Only a few references on the subject could be foimd 1-6). In the present article, differential thermal studies of a number of solid catalysts like chromic oxide gels, ferric oxide gels, and chromic oxide-ferric oxide are reported. An attempt has also been made to correlate the data with x-ray... 

However, as with the penetration theory analysis, the difference in magnitude of the mass and thermal diffusivities with cx 100 D, means that the heat transfer film is an order of magnitude thicker than the mass transfer film. This is depicted schematically in Fig. 8, The fall in temperature from T over the distance x is (if a = 100 D) about 0% of the overall interface excess temperature above the datum temperature T.. Furthermore, in considering the location of heat release oue to reaction in the mass transfer film, this is bound to be greatest closest to the interface, and this is especially the case when the reaction becomes fast. Therefore, two simplifications can be introduced as a result of this (i) the release of heat of reaction can be treated as am interfacial heat flux and (ii) the reaction can be assumed to take place at the interfacial temperature T. The differential equation for diffusion and reaction can therefore be written... 

Reading, M., Price, D. M., and Orliac, H. (2001), Measurement of crystallinity in polymer using modulated temperature differential scanning calorimetry, in Material Characterization by Dynamic and Modulated Thermal Analysis Techniques, American Society for Testing and Materials, Riga, A. T. and Judovits, L. H., eds ASTM, STP 1402. 

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