Irreversible process energy degradation

F Energy per unit mass degraded because of irreversibility of process J/kg l2t 2... 

The self-discharge phenomena are revealed by the continuous decrease of the low energy bands characteristic of the doped states and by the corresponding increase of those characteristic of the undoped state. These phenomena are not easy to explain. One important fact is that the self-undoping processes do not induce irreversible degradation of the... 

As a result of the irreversible or spontaneous process, the system has become degraded, i.e., energy which was available for doing useful work to the surroundings has become converted into thermal energy (heat) in which form it is no longer available for external purposes. 

First of all, we will touch a widely believed misunderstanding about impossibility of using the second law of thermodynamics in the analysis of open systems. Surely, the conclusion on inevitable degradation of isolated systems that follows from the second law of thermodynamics cannot be applied to open systems. And particularly unreasonable is the supposition about thermal death of the Universe that is based on the opinion of its isolation. The entropy production caused by irreversible energy dissipation is, however, positive in any system. Here we have a complete analogy with the first law of thermodynamics. Energy is fully conserved only in the isolated systems. For the open systems the balance equalities include exchange components which can lead to the entropy reduction of these systems at its increase due to internal processes as well. 

Entropy production is a measure of dissipated useful energy and degradation of the performance of a process the level of dissipation depends on the extent of irreversibilities. 

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