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New magnetic nanocomposites: Polyurethane/ Fe3O4-synthetic talc

“…6 and Table 3 corroborates that the obtained nanocomposites behavior as a ferromagnetic material. The spectrum is decomposed in 3 sextets, two sextet components corresponding to [Fe 3+ ]A and [Fe 3+ /Fe 2+ ]B in site of nanomagnetite (size of particles around 10 nm) and the third component with a broad distribution corresponding to interface, where the diffusion of Mg and Fe cations can take place, as suggested by Handke et al [27]. The result indicates clearly that the interface between nanomagnetite and talc is on the edge of talc particle.…”

Structure, composition and crystallinity of epitaxial magnetite thin films

“…The room temperature Mössbauer spectrum of magnetite consists of two sextet components corresponding, respectively, to Fe 3þ A ions at the tetrahedral A-sites and the Fe 2:5þ B -like average signal from the cations at the octahedral B-sites. The intensity ratio b = I(B)/I(A) of the two spectral components is a sensitive measure of the stoichiometry (b = 1.88 for the perfect stoichiometric magnetite) [14]. It has been proved that for the systems with reduced dimensionality e.g.…”

“…It has been proved that for the systems with reduced dimensionality e.g. MBE thin films, the conversion electron Mössbauer spectroscopy (CEMS; in particular for the films prepared with a pure Mössbauer isotope) provides a possibility to characterizing simultaneously chemical, structural and magnetic properties with monoatomic-layer sensitivity [13,14]. The combined in situ LEED, CEMS and STM studies of epitaxial magnetite thin films have indicated large size-effects reflected by a reduction of the Verwey temperature (T V ; for film-thicknesses less than 50 nm) and a strong deviation from the bulk properties due to formation of a magnesium rich phase near the MgO/Fe 3 O 4 interface (for film-thickness down to 10 nm range) [13,15].…”

Chemical, Magnetic and X-Ray Diffraction Studies of the Sediments from Oil Field in Argentina

“…Single line appearing with the largest fraction in our spectrum (35%) corresponds to Fe atoms in nonmagnetic surrounding. It may be related to superparamagnetic particles but it could be also interpreted as iron doped illite [10].…”