EVALUATION OF BASELINE NOISE IN ADSORPTION MICROCALORIMETRY

V. GARCIA-CUELLO, J.C.MORENO-PIRAJÁN, L. GIRALDO-GUTIÉRREZ, K. SAPAG, G. ZGRABLICH

Brasil

Congreso; 14th ICTAC – International Congress on Thermal Analysis and Calorimetry; 2008

This work presents an experimental methodology for carefully establishing noise on the signal baseline of thermal sensors used in a Calvet type Microcalorimeter, with twin cells and that uses 3D type sensors, developed in our laboratory together with International thermal Inc. This work shows the importance of the type of sensors that are used in calorimetry, since the detection limit depends on these sensors, especially when the Solid-Gas1-3 interphase is studied. Figure 1 shows the constructed equipment; this Microcalorimeter has two cells, one of which operates as a reference cell and the other one operates as a reaction cell, and the sensor type which allows more precision than other types of sensors. Figure 2 shows a typical potentiogram obtained with this Microcalorimeter, where a zoom is done to show the noise on the baseline of the thermometric signal. Table 1 shows obtained results changing operational conditions, versus the level of noise on the baseline.1-3 interphase is studied. Figure 1 shows the constructed equipment; this Microcalorimeter has two cells, one of which operates as a reference cell and the other one operates as a reaction cell, and the sensor type which allows more precision than other types of sensors. Figure 2 shows a typical potentiogram obtained with this Microcalorimeter, where a zoom is done to show the noise on the baseline of the thermometric signal. Table 1 shows obtained results changing operational conditions, versus the level of noise on the baseline.