Quasi-isothermal and isobaric

The thermal decomposition of a number of double complexes containing the [Cr(CN)6]3-anion has been investigated and the results obtained under quasi-isothermal and -isobaric conditions are summarized in Scheme 31.336 The CN-flipping reactions involved in the scheme resemble similar reactions of Prussian blue analogues such as Co3[Cr(CN)6]2 337 and Fe3[Cr(CN)6]2-338 The unusually low magnetic moment of Cr(CN)6Cr indicates considerable metal-metal interaction via the CN bridges. 

Paulik F, Paulik J, Erdey L (1958) The Derivatograph. I. An Automatic Recording Apparatus for Simultaneously Conducting Differential Thermal Analysis, Thermogravimetry, and Derivative Thermogravimetry. Z anal Chem 160 241-252. For standardization, quasi-isothermal and isobaric analyses and some example research with the Derivatograph see also (1966) Anal Chim Acta 34 419-426 Paulik F, Paulik J (1973) J Thermal Anal 5 253-270 (1975) 8 557-576. 

Isa and Oruno describe a method that enables identification of intermediates (in the gypsum dehydration process) more easily. The method involves the use of simultaneous TG-DTG-DTA under various sealed atmospheres corresponding to three systems—open completely, sealed, and quasi-sealed. Endothermic DTA peaks appear earlier (129 and 133°C) than the point of decreasing TG. This technique, resembling the quasi-isothermal and isobaric thermogravimetry (Q-TG), is superior to the latter in that it needs less of the sample. 

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