An isothermal calorimeter for solid-state reactions

The design and operation of an isothermal calorimeter is described. The calorimeter is suitable for studying solid-state reactions of long duration in the temperature range 40-300°C. Advantage is taken of the natural damping of thermal fluctuations in a massive body to achieve a temperature stability of better than ± 10−3 degC. In the temperature range 150-240°C the maximum sensitivity is 0·1 cal h−1.