Effect of Particle Aggregation

However, as a means of studying the filtrability of suspensions and the effect of particle aggregation, either in fundamental work or in practical applications, it could prove to be useful. 

Figure 16. Effect of particle aggregation on the back-scattered light intensity profile of food emulsion, containing 20 wt% emulsified fat, at 5 °C (green light).

Although field-flow fractionation was first developed in the 1960s (II), the first major study of colloidal silica by FFF was not reported until 1978 (4). At that time it was shown that the subtechnique of flow FFF could be used to fractionate colloidal silica down to a particle size of 0.01 pm (see Figure 2). The fractionation was verified by electron microscopy. Size distribution curves were obtained under different experimental conditions and shown to be consistent with one another. The effects of particle aggregation were examined. 

Effect of Particle Aggregation on Elementary Microflotation Act and Dynamic Adsorption Layer... 

Reinforcement depends on two features the number of interactions at the interface between polymer and filler (which is mainly controlled by the low primary particle size in conjunction with the surface activity) and the hydrodynamic effects of particle aggregation and agglomeration (which are linked with shear modulus and hysteresis during dynamic or static deformation). 

The theory of irreversible diffusion-controlled reactions is discussed in Chapter 6 the effects of particle Coulomb and elastic interactions are analyzed in detail. The many-particle effects (which in principle cannot be explained in terms of the linear theory) are demonstrated. Special attention is paid to the pattern formation and similar particle aggregation in systems of interacting and noninteracting particles. 

As earlier for the case U b = 0 (Fig. 6.35), the correlation functions XA(r,t) and Y(r, t) shown in Fig. 6.38 (a) and (b) demonstrate appearance of the domain structure in a reaction volume with interacting particles, having the distinctive size = y/Dt. Interaction within AB pairs holds at the relative distances r re (at long times rc < takes place) and only slightly modifies the AB pair distribution on the domain boundaries, where the reaction takes place, but do not influence essentially the entire mechanism of the domain formation (the effect of statistical aggregation). 

Mass or heat transfer between fluid and particles is related not only to fluid-particle contacting, but also to the exchange between the dense and the dilute phases. Therefore, further efforts are needed to unravel how the latter effect, which is characterized by repeated dissolution and reformation of particle aggregates, should be incorporated in order to evaluate the overall mass or heat transfer process. 

Simulation can also be applied to longer length-scale phenomena. Examples include attempts to model the structural and mechanical properties of catalyst pellets, the mesopore structure of particle aggregates and phenomenological studies of crystallization. Here I mention just two examples, studies of crystallite morphology and quantitation of the effect of pore blockages on effective sorption capacities. 

Kobayashi, M. et al., Aggregation and charging of colloidal silica particles Effect of particle size, Langmuir, 21, 5761, 2005. 

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