Wetting performance evaluation method

Knife test (KNF) The test is done by making two intersecting scratches through the paint film to the substrate with a sharp steel knife. Adhesive or cohesive failures are evaluated by peeling the coating from the intersection point and outwards. Common for the three adhesion evaluation methods are that the test is performed on immersed and non- immersed panel-half (referred to as respectively "wet" and "dry" adhesion). The type of rupture is reported, and the severity is judged on a scale from 5 (perfect) to 0 (poor). 

The wetting balance is a comparatively new method of assessing wetting. In the microelectronics industry, its use to measure the wetting performance of solders and fluxes is pervasive. It is considered by some to be the most versatile method for evaluating solderabiUty. Its primary advantages are (a) it provides a near real-time quantitative output of force (b) substrates in the shape of microelectronic components can be used as specimens and (c) it can be used equally well to evaluate the wetting performance of solders and fluxes. 

The effect of catalyst wetting on the performance of a bench-scale trickle-bed reactor was also theoretically evaluated by Sylvester and Pitayagulsarn.94,9S Using the method of moments of Suzuki and Smith,93 they developed a procedure to show the combined effects of axial dispersion, external diffusion, intraparticle diffusion, and surface reaction on the conversion for a first-order irreversible reaction in an isothermal trickle-bed reactor and evaluated the effect of catalyst wetting on these combined effects. 

Then, the effectiveness of the ADS/PRC method in promoting the dispersion of the supported phase and consequently the reactivity of FeOx/Si02 system in MPO, has been evaluated by comparing the performance of catalysts prepared using either Si 4-5P or F5 silica carriers by INC/WET and ADS/PRC methods, respectively. Activity data at 650°C of the various catalysts in the MPO reaction, with reference to Si 4-5P and F5 silica carriers, are presented in Table 2 in terms of hourly CH4 conversion (Xch4,h, %), product selectivity (Sx, %) and reaction rate (rate, pmolcH4 s "g ), while the relative space time... 

The technique that lends itself best to small-scale evaluation is low pressure agglomeration (Chapter 5, Fig. 5.10, and Section 6.2.2), which may be followed by spheroni-zation. Since in this method of pressure agglomeration a wet mixture is passed through the openings of a screen or a thin perforated sheet, very little pressure is exerted and it is essentially a shaping process [B.97]. Therefore, even if tests are performed on a small perforated die, in regard to product characteristics, the results are also representative for larger units. 

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