Isothermal covers both static jacket (CAL2K) and Isoperibol systems.
Isoperibol calorimeters control the temperature of the surrounding jacket so that it is at a constant temperature.
The static jacket has a thermal capacity such that the temperature of the surrounds remains nearly constant without active control. The variation in the static jacket is measured and compensated for.
Bomb construction:
CAL2K: The vessel has a stainless body with an aluminum sleeve pressed over it.
Isoperibol: Stainless steel.
Temperature measurement of surrounds:
CAL2K: The ambient box containing the polystyrene (static jacket) is monitored throughout the determination.
Isoperibol: The jacket is water maintained at a constant temperature.
Temperature measurement of energy:
CAL2K: Sensors placed between the stainless steel body and the sleeve measure the energy released during a determination. A microprocessor is built into the vessel making the calibration independent of the calorimeter.
Isoperibol: The vessel is placed in a bucket of water and then the temperature of the water in the bucket is measured.
