Metastable ambient environments

The reason that the appropriate practical choice for T, pf, u. .f are the steady values in the metastable local ambient environment is that the available energy Bq is not accessible practically--as long as the metastability cannot be overcome with practical means. If the metastability can be overcome, then, of course, the proper selection for T, p, would be the final values in the ultimate dead state of the ambient surroundings. 

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