Use of the Washburn—Rideal Equation for Studying Capillary Flow in Porous Media

The wetting and interfacial properties of alumina surface treated with dipalmitoylphosphatidylcholine and lipase enzyme

“…More details of the theory and experimental method were described elsewhere [13][14][15][16][17][18]. Analogically, as it was done in our previous papers [11,12], three series of wicking experiments on the alumina plates were conducted: for the bare surfaces (bare), for the overnight precontacted surfaces with the vapors of probe liquids in a covered Petri dish (precontacted) and for the surface treated with DPPC in NaCl solution (treated).…”

“…It should be mentioned that the contact angles are not equivalent to the Young's contact angles, that would be measured for the liquid drop on the flat solid surface [13][14][15][16][17][18]. Consequently, the surface free energy components calculated based on such dynamic angles are apparent values.…”

Determination of Hydraulic Conductivity Based on (Soil) - Moisture Content of Fine Grained Soils

“…This time was then compared to a reference sample with cos = 1 (contact angle = 0°). This method assumes that the differences in the penetration rate are due only to differences in contact angle, after taking surface tension and viscosity into account (Yang & Zografi, 1986). …”

Influence of Crystal Habit on the Surface Free Energy and Interparticulate Bonding ofL-Lysine Monohydrochloride Dihydrate

“…The rate of crosshead movement for the tensile strength experiments was predetermined, such that any difference in the strain rate sensitivities of the samples did not affect the tensile strength measurements (31). The tensile strength was obtained as Tensile strength ϭ 0.16 ϫ F max (10) where F max is the stress required by the compacts to undergo tensile failure. The dynamic indentation hardness, P d , of a compact was determined by means of the pendulum indentation method (32) as…”

“…Alternatively, the Washburn (8) equation has been used to calculate the surface free energy from the rate of penetration of the measuring liquid into a powder bed (9). Problems associated with the liquid penetration method were described by Yang and Zografi (10). Sheridan et al (11) calculated molecular orbital indices (electron density, frontier electron density, and superdelocalizability indices) from portions of molecular structures liable to form hydrogen bonds, and found a good correlation between the indices and contact angle measurements with water.…”