Now showing items 1-10 of 41
The influence of heat treatments on order–disorder phenomena in a naturally occurring manganese‐ferrite
(The American Institute of Physics, 1994-05-15)
Naturally occurring samples of iwakiite, Mn1.1Fe1.9O4, have been annealed for 17 and 77 h at 1000 K in an investigation of order–disorder phenomena in Mn–Fe oxide spinels. Two distinct magnetic hyperfine patterns, which ...
The 57Fe Mössbauer spectra of oriented single‐crystal and powder PbFe12O19 (abstract)
(The American Institute of Physics, 1991-04-15)
The recent determination of the crystal structure of PbFe12O19 by means of single‐crystal x‐ray diffraction has made it possible to carry out a definitive and comparative analysis of the structure‐property relationship of ...
57 Fe NCR of Fe phases in “magnetic cassiterites”
(Springer-Verlag, 1975-09)
A pyralspite garnet from an anomalously magnetic concentrate of a pegmatitic cassiterite ore has been investigated using 57 Fe nuclear gamma-ray resonance spectroscopy. The quadrupole splitting and isomer shift values of ...
Magnetism and archaeology: Magnetic oxides in the first American civilization
(Elsevier, 1977)
Archaeological excavations at sites of the Olmec civilization (1500 to 500 B.C. in present-day Mexico) have unearthed artifacts formed from massive iron oxide ores. Iron oxide ores were ground and shaped into highly polished ...
High Temperature Electronic Structure of Fe3O4Fe3O4
(The American Institute of Physics, 1976-09-01)
The high temperature electronic structure and conduction mechanism in Fe3O4Fe3O4 have been investigated through correlations of resistivity and magnetoresistance data with 57Fe NGR. Similar to the resistivity, the relative ...
Order‐disorder and magnetic exchange interactions in substituted strontium hexaferrite SrAxFe12−xO19(A=Ga, In)
(The American Institute of Physics, 1994-05-15)
The unusual magnetic behavior of the 12k site in SrGaxFe12−xO19 (0.3≤x≤6.0) and SrInxFe12−xO19 (0.3≤x≤1.4) has been investigated by means of 57Fe Mössbauer spectroscopy at 298 K. The bifurcation of the 12k Mössbauer ...
Investigation of Virgin Coals and Coals Subjected to a Mild Acid Treatment
(Kluwer Academic Publishers; Springer Science+Business Media, 1998-03)
A quantitative determination of the relative marcasite/pyrite contents in virgin coals is possible by means of 57 Fe Mössbauer spectroscopy. Complications arise, however, when iron-containing silicates, carbonates, or other ...
Solid state and magnetochemistry of the SrO‐Fe2O3 system IV. Synthesis of SrFe12O19 from coprecipitated precursors
(The American Institute of Physics, 1981-03)
By means of 57Fe Mössbauer spectroscopy and powder x‐ray diffraction techniques, it has been determined that the formation of SrFe12O19 from coprecipitated ferric hydroxide and strontium laurate follows a reaction mechanism ...
Intra Site Cation Ordering and Clustering in Natural MnZn Ferrites
(The American Institute of Physics, 1976-09-01)
Cooling rates of 10−3 K/yr. permit naturally occurring MnZn ferrites (franklinites) to be in thermodynamic equilibrium at ambient temperatures with respect to both electrostatic and elastic energies. The elastic strain ...
The structure–property relationships in M‐type hexaferrites: Hyperfine interactions and bulk magnetic properties
(The American Institute of Physics, 1993-05-15)
57Fe Mössbauer spectroscopic measurements have been made at 296 K on single crystals of MFe12O19 (M=Ba, Sr, Pb) oriented parallel and perpendicular to the c axis, permitting the establishment of the systematics of the ...