TWO different spinels, analyses of which are given, occur in the layered ultramafic rocks at Dawros. Chrome spinel occurs both as gravity-stratified cumulates and as complex orbs, while an Al-rich spinel is both in rocks of the main Dawros magmatic sequence and in an association with an aluminous bronzite, which may originate by recrystallization. It is concluded that while the chrome spinel is...

cobalt ferrite is an important magnetic material due to their large magneto-crystalline anisotropy, high cohercivity, moderate saturation magnetization and chemical stability.in this study, cobalt ferrites nanoparticles have been synthesized by the co-precipitation method and a new microemulsion route. we examined the cation occupancy in the spinel structure based on the “rietveld with energies...

The temperature dependence of core loss in cobalt substituted Ni-Zn-Cu ferrites was investigated. Co ions are known to lead to a compensation of the magnetocrystalline anisotropy in Ni-Zn ferrites, at a temperature depending on the cobalt content and the Ni / Zn ratio. We observed similar behaviour in Ni-Zn-Cu and it was found that the core loss goes through a minimum around this magneto-crysta...

Spinels from cumulus and non-cumulus members of the 0thris ophiolite display a considerable variation in composition. Cumulus pierites and gabbros contain either a primary chromite and/or a reaction spinel formed by reaction with co-existing sili?ate,-" (Cr--A1 varia tion) or intercumulus liquid (Cr--Fe variation). Non-cumulus peridotites contain spinels which vary along a Cr--A1 trend. Harzbur...

Spinels are compounds that have the general formula AB2O4 where A and B are metallic cations. The formal charges of A and B are strictly specifi ed and they are a criterion of the spinel type. There are three types of spinel compounds, the so-called 2-3, 4-2 and 6-1 spinels, where the numbers indicate the formal charges of the cations. The fi rst cation of each pair occupies a tetrahedral site ...

CoFe 2 O 4 and NiFe spinel ferrites were obtained by microwave-assisted sol–gel combustion synthesis using three different types of chelating/combustion agents: maleic acid, citric urea. The nanomaterials produced characterized from the structural, morphological, textural, magnetic viewpoints. prepared employed as adsorbents for removal Orange-II dye synthetic wastewaters. nickel ferrite sample...

Lanthanum substitution on spinel Nano particles has a significant repercussion the several features of materials. Sol–gel (auto-ignition) allowed for rare earth lanthanum ion (La3+) ferrite with composition SrLaxFe2-xO4 (where 0.00 ≤ x 0.10). As result base’s presence, systems structural, magnetic, electrical, and magnetic properties are all modified. X-ray diffraction (XRD) assessed structural...