Calorimetry of the PD ED2O System: from Simplicity via Complications to Simplicity.

We present here one aspect of our recent research on the calorimetry of the Pd/D2O system which has been concerned with high rates of specific excess enthalpy generation (> 1kWcm-3) at temperatures close to (or at) the boiling point of the electrolyte solution. This has led to a particularly simple method of deriving the rate of excess enthalpy production based on measuring the times required to boil the cells to dryness, this process being followed by using time-lapse video recordings. Our use of this simple method as well as our investigations of the results of other research groups prompts us to present also other simple methods of data analysis which we have used in the preliminary evaluations of these systems. General Features of our Calorimetry Our approach to the measurement of excess enthalpy generation in Pd and Pd-alloy cathodes polarised in D2O solutions has been described in detail elsewhere (see especially (1-5); see also (6)). The form of the calorimeter which we currently use is illustrated in Fig 1. The following features are of particular importance