Wettability scenarios

Worden et al. 1998). Wettability would also have to be taken into account the present calculations assume a water-wet system, where the diffusion of solutes in the water phase is retarded by sorption onto mineral surfaces (Ad assumed to be 5 in equation (13)), while components of oil and gas are not significantly slowed (Ad assumed to be 0). Clearly, other wettability scenarios (oil-wet or mixed wettability) could significantly affect the model results. 

End-use formulations should be used as the test substance. If an active ingredient is marketed in two commercial formulations, then both should be used in the study, since there may be differences in residue levels and dissipation rates, e.g., a wettable powder versus a liquid formulation. The best solution would be plots located at the same site for a side-by-side comparison. This should only be necessary at one of the sites. However, each formulation should be represented in the study unless a strong case can be made for a worst-case scenario. 

To illustrate previous comments, an attempt was made to compare estimated exposure levels of the different databases using one scenario, i.e. the downward groundboom application of a wettable powder (WP) formulation. In order to compare the outputs, specific input data must be selected. The input data presented in Table 5.13 for the identified scenario are considered to be a reasonable representation for all European databases. 

For liquids impacting at some velocity on nanofiber surfaces, the physieal scenario can change considerably. The impact of drops has been studied in depth in view of the possible development of spray cooling methods for surfaces coated by nanofibers. A significant penetration of liquids into nanofiber non-wovens is found, regardless of the specific wettability of the nanostructures, provided that incoming droplets are fast enough ( 1.5-3.0 m s ). °... 

The deposition scenario can be divided into two sections the kinematic and the actual deposition. In the first stage, the radius of the droplet base R correlates with fand is independent of the physical properties of the liquid and the surface. However, in the second stage, the physical parameters have their influence on the spreading. After the kinetic energy of the drop impact has been partly dissipated by the viscous forces and partly converted into the surface energy associated with the greatly increased free-surface area, the subsequent behavior of the lamella depends largely on the surface wettability. 

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