The Influence of a Long-Chain Hydrocarbon on the Retention of Probes Differing in the Type of Intermolecular Interactions. 
The surface properties of entirely hydroxylated, as well as significantly dehydroxylated, silica gel were investigated by means of the gas phase titration method.  n-Tridecane was applied as blocking agent, while n-octane, benzene, and chloroform were the testing probes.  The results obtained were compared to those from the previous investigation, where ethylmethylketone was used as blocking agent.  After the proper recalculation of n-tridecane surface concentration it was stated that the titration curves for n-octane coincided for both blocking agents.  The changes in nonspecific adsorption interaction do not depend on the type of the blocking agent intermolecular interactions.  Copyright 2000 Academic Press.