Wetting parameters

Wetting Parameters in the Detergency Equation. The detergency system has three interfaces which have three interfacial tensions at equilibrium with all three phases Ksw> Yfs and Yfw When only two phases are in equilibrium, three other surface tensions are possible Ysw> Yfs> Yfw (however, when the fiber is an insoluble solid, Ysw Y w> Ysw will be... 

Wilhelmy plate wetting parameters, such as plate velocity during immersion or emersion and halting the motion of the plate after immersion or emersion, have been shown to alfect the intrinsic hysteresis, which consequently affects the overall shape of the force loop [3]. These wetting parameters were found to affect FHT differently depending on whether pure water or an aqueous artificial tear solution was employed as the wetting medium. 

Another important wetting parameter is the work of wetting [70] or adhesion tension W , defined as ... 

Ramshaw, and Burns et al.) has shown that wetting films for p values within the metastable film region can be obtained. In particular, the use of preflooding of the disk or the use of surface roughening can push the limit of the wetting film thickness down to the lower end of the metastable film region, further details of which will be discussed in the later sections. However, the above wetting parameter calculations can be used to examine how likely it is for a process to achieve a stable wetted disk surface. 

Fig. 14 presents the stationary solutions of eq.(43) for different values of the dimensionless wetting parameter, woi, corresponding to different values of the wetting interaction strength, w, and the initial film thickness, ho. One can see... 

Figure 4. Experimentally obtained relationship between the wetting parameter kb and the (apparent) water contact angle. The measurements refer to a number of different types of rough surfaces with same hydrophobic material properties (all samples were coated with a thin RF sputtered Au layer and a molecular decanethiol film to obtain intrinsic CA about 110 ).

Figure 20. Comparison of wetting parameter Kjj within specific spatial frequency decades for Z1O2 and AI2O3 single layer coatings.

Values of the wetting parameter kb, calculated for specific spatial frequency decades within the range / = (10 . .., 10 ) pm are given in Fig. 20. Obviously, only roughness components at spatial frequencies above / = 1 pm , which means structured components with nanometer dimensions, are relevant for... 

Figure 8 Experimentally measured shifts in the melting temperature for confined nanophases, showing the effect of pore width and wetting parameter. Here, CNT, multiwalled carbon nanotube. MCM-41 and SBA-15 are silica materials. Figure taken...

Yekeler M, Ozkan A. Determination of the breakage and wetting parameters of calcite and their correlations. Part Part Syst Charact 2002 19 419-425. 

Kj values (Table 7.1) were calculated from the PSD functions for four different spatial frequency decades between 0.01 pm and 100 pm. The samples 4 and 5 exhibit the highest wetting parameter in this sample series, and hence for both samples the best wettability, i.e. the lowest CA, is expected. 

Table 7.1 Root mean square roughness from at least two individual measurement positions in different scan areas, and wetting parameter k, determined within the investigated spatial frequency range, of the steel samples with graded surface roughness.

Figure 7.7 Apparent CA behavior of car engine oil drops on steel surfaces with graded surface roughness as a function of the wetting time t. Additionally, the wetting parameters for all samples are listed in the legend.

Table 7.2 Wetting parameters and apparent CA values for different wetting times t of the steel surfaces with graded surface roughness.

As can be seen from Figure 7.4(b), there is a third wetting parameter, called the work of wetting , (or more commonly, the wetting tension or adhesion tension ). This parameter is defined as the work expended in eliminating a unit area of the solid-liquid interface while exposing a unit area of the solid-vapour interface, as follows ... 

They generally suggest an increase of the Reynolds number exponent when using less wettable packings. This is well accounted for by Eq. 22 which predicts an exponent equal to 1-2/3 f i.e. increasing with Re. This role of wetting paramete ... 

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