Thermoanalytical instrument

D. Dollimore, Thermoanalytical Instrumentation, in Analytical Instrumentation Handbook, G. W. Ewing, ed., Marcel Dekker, New York, 1990, pp. 905-960. 

R. F. Speyer, Innovative Applications of Computerization in Thermoanalytical Instrumentation , Ceramic Bulletin, 69 (1) 85-90 (1990). 

Gallagher, P.K. (1997) Thermoanalytical instrumentation, techniques and methodology, in Turi, E. A. (Ed.) Thermal Characterization of Polymeric Materials, San Diego, CA Academic Press. 

Thermoanalytical instruments allow the study of chemical and physical changes that occur with temperature, allowing the characterisation of materials and an understanding of their thermal events. 

Every two years, a fundamental review on thermal analysis is published in Analytical Chemistry, in which the development of new methods and the main applications to calibration, thermodynamics, kinetics, polymers, inorganics, pharmaceutical, biological, foods, etc. are reported [1-3]. Several articles regarding coordination compounds are cited and critically described. An update of the applications of evolved gas analysis (EGA), coupled to the thermoanalytical instruments, is also published every four years, and many studies on coordination compounds are cited [4-7]. 

In this respect, progress in thermophysical and thermoanalytical instrumentation is apparently proceeding in two opposite directions ... 

The thermoelectric voltage developed in a thermoelectric couple is a function of the temperature difference between the measured and reference sites. The reference ends are connected with further conductors in an electrically and thermally insulated space to avoid parasitic voltages (compensation leads, shielded conductors, shortest path to encircle smallest possible, holder induced leaks). Temperature measurements by thermoanalytical instruments are conventionally calibrated by a set of ICTAC-approved standards, convenient for both the DTA/DSC [594,614] and TG [615] techniques. 

The simplest way of coupling is by using a heated capillary with laminar flow conditions to extract the gas from the TG, and an orifice arranged at the outlet side of the capillary for a molecular flow into the ionization chamber of the MS. This coupling needs little preliminary modification of the thermoanalytical instrument. The capillary can be heated to 150°C or 200°C, but this cannot exclude condensation effects in some applications. The length of the capillary, usually Im, can cause time or mass dependent separation of gases when they pass through it. 

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