Brief Introduction Into Surface Rheology

The main principles of surface rheology were set up by Landau Lifschitz (1953), Stuke (1961), Levich (1962), Lucassen (1968), Wasan et al. (1971), van den Tempel (1977), Goodrich (1981). Goodrich(1969), Izmailova (1979), Lucassen-Reynders (1981), Wustneck Kretzschmar (1982) and, more recently, Edwards et al. (1991) and Miller et al. (1994) have provided overviews. 

In the notation of tensor components we are using some symbols taken from the classical work of Landau Lifschitz (1953), especially 

In Fig. 3.5. the tensor components for shear and compression/dilatation at a small cube is shown. 

From this figure we learn that pure deformation without any change in size (pure shear) and change in size without any change in shape of the body (dilatation or compression) have to be considered. For the latter case the tensor of strain becomes Uj,j 8 (Landau Lifschitz 1953). Any deformation can be given as the sum of pure shear and dilatation deformations. Therefore, we get 

We will now examine the simplest rheological model, the Hooke law for elasticity and Newton law for viscosity. In Hooke s law the tensor of strain Un is a linear fimction of the stress tensor of S, i.e. the deformation is proportional the acting forces. If the inertial stress, the elastic or Hooke s stress and the viscous stress are additive, we can write 

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The lateral liquid und surface layer movement is influenced by surface rheology which is coupled with the exchange of matter process (surface relaxations). This coupling creates great difficulties in the quantitative description of dynamic adsorption layers (DAL). A brief introduction into surface rheology and surface relaxations is given and results are specified for use in Chapters 8,9,10 and 11. 

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