Abstract
The influence of the surroundings on the output signal of a colorimetric unit composed of a metallic cell, a circuit with four thermopiles and a heat sink, is studied. The conditions of the surroundings are: i) room temperature, around 291 K, without any kind of insulation; ii) insulation with expanded polyurethane and room temperature; iii) insulation with acrylic and with temperature control at 298±0.01 K
It is established that the condition that keeps the output signal stable is that in which the calorimetric unit is isolated in a 60 L acrylic box and temperature control is maintained.
A value for the sensitivity of the calorimetric unit of around 1.87×10−2 ±8.00×10−4 VW−1 is found which permits the measurement of thermal effects above 30 mW.
Acknowledgments
The authors thank the Chemistry Departments of Universidad Nacional de Colombia and Universidad de los Andes and the Master Agreement established between these two institutions.