Structural characterization of urethane/urea elastomers undoped and doped with magnetic nanoparticles by proton NMR relaxometry and X-ray diffraction - Sena, Cleidilane Oliveira; Figueiredo Neto, Antonio Martins; Sebastião, P J; Godinho, M H (Encontro Nacional de Física da Matéria Condensada, 2009)