4, Table ) the surface RAE oxidation states of the spent catalyst sample under UHV (c M,M>C OPQ ), the surface RAE oxidation states under dry, alkane-rich and wet feeds (c M,@"J OPQ , c M,9:;9<# OPQ , and c M,e#C OPQ , respectively) and the pore volume of the fresh catalyst (Ä $" >?"# ) appear. These parameters correlate with the surface redox activity and local transport. In the relatively complex expression of the model, the differences between oxidation states measured in situ at different chemical potentials, i.e., (c M,@"J OPQ -c M,9:;9<#