Long range repulsive forces

The DLVO theory [88,89], a landmark in the study of colloids, interprets stability as dependent on the competition between the long-range repulsion forces of similarly charged... 

The thicknesses of free soap films and liquid films adsorbed on surfaces (Figs. 1.26d and 1.26e), which can be measured using optical techniques such as reflected intensity, total internal reflection spectroscopy, or ellipsometry as functions of salt concentration or vapor pressure, can provide information on the long-range repulsive forces stabilizing thick wetting films. We see an example of this in Chapter 11. 

The basic principle of self-assembly is based on the simultaneous coexistence of two parallel forces [85, 86], long-range repulsive forces and short-range attractive interactions. 

The long-range repulsive force increases somewhat when the polyelectrolyte concentration is increased to above 20 ppm. This indicates that the charges in the adsorbed polyelectrolyte layer slightly overcompensate the charge of the substrate surface, and that the polymer-coated surface now has a net positive charge. It is interesting to note that under these conditions the... 

It may be noted that the forces between polyelectrolyte-coated surfaces at higher salt concentrations (> 10 2 M) are more complex than those observed at low ionic strength. In these cases long-range repulsive forces of clear nonequilibrium nature are often observed. This results in hysteretic forces, and previous compressions may affect the forces measured on subsequent approaches [85,86],... 

Dynamical aspects of Q2D suspensions of spherical colloids and asymmetric colloid mixtures with long-range repulsive forces have been investigated by Brownian dynamics simulations [193-195]. These works emphasize dynamic scaling and the importance of hydrodynamic interactions on self- and tracer diffusion. 

Particles that interact with long range repulsive forces behave much like hard spheres when the distance between the particles is larger than the range of the repulsive force. This is usually the case when the volume fraction is low (average... 

A typical FDC between an AFM tip and a surface is depicted in Fig. 2, where there are two distinct traces, the approach and retract traces [34,72]. At the start of the FDC, the distance between tip and surface is so great that there is no interaction between them. As the approach begins, the distance between tip and surface reduces such that a point is reached in which attractive forces (such as van der Waals) cause the tip to instantaneously snap towards the surface. It is possible for long-range repulsive forces to dominate prior to the tip-surface contact, in which case the cantilever bends away from the surface before the snap-in [72]. 

Then, a plane-parallel film of radius R and typical thickness from 15 to 200 nm forms (see Fig. 33c and Sec. VTI.C). When the long-range repulsive forces are strong, an equilibrium (but thermodynamically metastable) primary film forms cf. point 1 in Fig. 17a. [This film is also called the common black film (CBF)]. 

A 2D system of particles interacting through long range repulsive forces... 

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