Energy Distribution of Carbon Black Surfaces

The integral in Eq. (6) is normalized to unity. This has to be taken into consideration if solid samples with different specific surface areas are compared. 

For an evaluation of the local model isotherm 6(p,T,Q) with constant interaction energy Q, the effects of multi-layer adsorption and lateral interactions between neighboring adsorbed molecules are considered by applying two modifications to the Langmuir isotherm (i) a multi-layer correction according to the well known BET-concept and (ii) a correction due to lateral interactions with neighboring gas molecules introduced by Fowler and Guggenheim (FG) [105]  

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