When highly divided spinel fenites become reactive enough with oxygen, to allow the oxidation of the Fe ions at low temperature and of substitute cations too, when these cations are capable of different valence states. We prepared fine particles of spinel ferrites substituted by Mn, Mo, Cu, by "chimie douce", especially from oxalate precursors and used them to reveal and to study the oxido-redu...

The microstructure, static, and dynamic magnetic properties have been investigated for BaCoZnFe16O27 doped with small amounts of V2O5 from 0 to 1.5 wt %. The results show that the doping of V2O5 can significantly improve the dynamic properties of W-type barium ferrites at microwave frequency. As compared to the undoped sample, the permeabilities m08 and mmax 9 increase by about 42% and 67%, res...