Sol Sol - - gel process: an overview gel process: an overview Ana C. Marques 22 nd of June, 2007 Lehigh University Departamento de Engenharia de Materiais / ICEMS, Instituto Superior Técnico, TULisbon, Av. Rovisco Pais, 1049-001 Lisboa, Portugal Department of Materials Science and Engineering, Lehigh University, Bethlehem, PA 18015, USA