Microsymposia(i) The theoretical developments made to analyse quantitatively the GISAXS patterns beyond the classical approximations, in particular to account for the profile of refraction index and the particle-particle correlations.(ii) The self similarity during the dynamic coalescence of Au/ TiO2(110) on the size distribution but also on the spatial ordering of the particles and its link with the randomness of the nucleation centers.(iii) The sintering of nanoparticles during the course of the CO oxidation reaction and the link between particle size and chemical reactivity measured by mass spectrometry.