Jean-François Daïan is a retired and voluntary researcher at LTHE (Laboratoire d’Étude des Transferts en Hydrologie et Environnement) in Grenoble, France, having worked there as a lecturer for nearly 30 years before his retirement. His main fields of research include porous media, pore structure characterization: mercury porosimetry and the application of percolation theory. He is the co-author of the XDQ (Xu Ke, Quenard, Daïan) model.