In addition, sound assisted fluidization has been indicated as
a suitable technique to have a broad control of the size of nanoparticles aggregates
(5, 9, 10, 11, 12). However, in all cases, even if a fluidization regime has been
obtained, there were indications that cohesive forces between elementary particles
continued to play a key role determining the form and size of loose agglomerates
that are the pseudo-particles really characterized by a fluidizing state.