The second law of thermodynamics and optimal bounds for the efficiency of cyclic processes (Q1333616)

The paper shows the equivalence of Clausius' inequality to a certain bound on the efficiency of any general cyclic process, as well as the equivalence of the entropy inequality to a certain bound on the work performed in any general process. These bounds are expressed in terms of a geometrical characteristic of the functions accounting the absorption and emission of heat in terms of the temperatures at which the exchange takes place, namely the ``baricenters'' or ``first moments'' of these functions. Further, the analysis is extended to take into account the temperatures of the environment.