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The Haber-Weiss cycle -- 70 years later: an alternative view
Abstract:
In a recent review published in this journal,(1) Koppenol traced the history of the Fenton reaction and of the catalytic decomposition of H(2)O(2) by iron salts. If his purpose was to shed light on current understanding of related chemistry in biological systems, he failed. Moreover, he managed to sow confusion by inaccurate reporting of the work of others. What follows is an attempt to point out these shortcomings and thus to clarify the situation.
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Cyclic Processes And Isolated Systems
In the case of a non-isolated system, the change in the internal energy is zero only if the process is cyclic. A thermodynamic process is considered cyclic if the system undergoes a series of changes and returns to its initial state.
Consider a cyclic process that returns to its initial state, undergoing a four-step process. The heat transfer along each path...
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