Conform glosarului de cromatografie indicat.

At the stationary phase surface, the molecule either pulls itself free and evaporates or returns into the liquid http://www.restek.com/Technical-Resources/Technical-Library/...

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Note added at 59 mins (2011-08-23 20:47:59 GMT)
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Din Lloyd R. Snyder, Joseph J. Kirkland, John W. Dolan: Introduction to Modern Liquid Chromatography, Third Edition, Wiley 2009 (paginile rezultate la căutarea "stationary phase")

Packings made in this way often exhibit the highest column efficiency because of rapid diffusion of the solute into and out of the less-crowded stationary-phase layer. Stationary phases with certain ligands (e.g., those containing reactive amino or hydroxyl groups) cannot be prepared from chlorosilanes because of undesirable
secondary reactions of the ligand. These reactive stationary phases are instead made from alkoxysilanes, as in Figure 5.14c or d.
Sterically protected stationary phases are available with a variety of ligands (e.g., C8, C18, cyano, phenyl), each of which show exceptional stability for use with low-pH mobile phases.
Thus the pressure P required to force the mobile phase into a particle pore of diameter dpore is
P = −4γ cos θ/dpore (5.2)
where γ is the surface tension of the mobile phase, and θ is the contact angle between the stationary and mobile phases. The value of θ is >90◦ for a C18 stationary phase and water as mobile phase, meaning that pressure is required to force water into the pores.


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Note added at 1 hr (2011-08-23 20:54:43 GMT)
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Din Paul C. Sadek: Illustrated Pocket Dictionary of Chromatography, Wiley 2004-Interscience

stationary phase = The retentive component(s) of the packing
material. In adsorption chromatography the packing material itself is
the stationary phase, whereas in partition chromatography the
adsorbed liquid phase or bonded phase is the stationary phase. (pag. 188)

surface area = The surface area of a porous packing material is commonly determined through the calculation of nitrogen isotherms run at -19°C (see BET test method). Surface area is typically expressed as m2/g of packing. High-surface-area packing materials are desirable because this is where the solute equilibrium occurs. Surface areas range from 10 to 450m2/g corresponding to pore sizes of 4000–50 Å, respectively. (pag 190-191)