1. Dipartimento di Ingegneria Civile
2. Chimica, Ambientale e dei Materiali
3. Universitá di Bologna
4. Bologna 40131
5. Italy
6. Institute of Physics
7. West Pomeranian University of Technology Szczecin
8. Szczecin 70-310
9. Poland
10. Institute of Materials Science and Engineering
11. Instituto de Estructura de la Materia
12. IEM-CSIC, Serrano 121
13. Madrid 28006
14. Spain