Remarks on calorimetric nomenclature

Modem biological calorimetry differentiates between quantitative and analytical calorimetry. The first is the classical one bound to the determination of thermodynamical data of enthalpy, entropy and heat capacity. The more modem analytical calorimetry looks whether heat producing processes are occurring and with which kind of time profile. This type is of great interest during metamorphosis of insects, adaptation phenomena to environmental factors or periodically repeated activities. Examples of such different applications of analytical calorimetry will be given below. 

Sometimes there is confusion due to different use of terms. Thermodynamics calls a process exothermic when heat is given off by the system and endothermic when it consumes heat. In biology, warm-blooded (homeothermic) animals like mammals and birds that produce heat to keep their body temperature constant are called endotherms and their behaviour endothermic, in contrast to the thermodynamical direction. Their counterparts with changing body temperatures are ecto-therms (not exotherms) or cold-blooded poikilothermic) animals. Nevertheless, all of them produce heat as a by-product of their metabolism so that they can be monitored by (exothermic) calorimetry. 

The term thermogram was used in the older literature for the calorimeter signal as function of time. Thermogram is now reserved by nomenclature for changes of 

Physiologists are rather conservative people and like to publish still in old units that do not agree with the SI norm. Even the large calorie Cal is sometimes found in the literature. In this survey all original data are transformed to the official power unit Watt (W) and the corresponding energy unit Joule (J). To facilitate the comparison of data Table 1 shows the appropriate conversion factors - but unidirectional  

Conversion of some frequently used old or odd units of energy and power into the correct SI units. 

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