New positive mixed alkali effect in V2O5.nH2O nanocrystalline films A. S. Abdel Moghny, Samia E. Attia Negm, Sh. Heikal and A. A. Bahgat Eur. Phys. J. B, 98 4 (2025) 65 Published online: 17 April 2025 DOI: 10.1140/epjb/s10051-025-00907-4