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ferrite spinels

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Journal Article
Published: 01 October 2007
European Journal of Mineralogy (2007) 19 (5): 707–716.
...Victoria S. Coker; Carolyn I. Pearce; Claus Lang; Gerrit van der Laan; Richard A. D. Pattrick; Neil D. Telling; Dirk Schüler; Elke Arenholz; Jonathan R. Lloyd Abstract Ferrite spinels, especially magnetite (Fe 3 O 4 ), can be formed either by geological, biological or chemical processes leading...
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Journal Article
Published: 01 May 2006
American Mineralogist (2006) 91 (5-6): 880–893.
...Carolyn I. Pearce; C. Michael B. Henderson; Richard A.D. Pattrick; Gerrit van der Laan; David J. Vaughan Abstract Cation distributions in natural ferrite spinels, some containing large amounts of Mg, Ti, Mn, and Zn, have been investigated using the element-, site-, and symmetry-selective...
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Journal Article
Published: 01 July 2020
Mineralogical Magazine (2020) 84 (4): 554–562.
..., a component of specialised light, highly corrosion-resistant alloys and as a catalyst in polymerising processes. However, it also has increasing use in superconducting magnets and as a dopant that can be used to tune the magnetic and electrical properties of technologically important ferrite spinels [(Fe, Me...
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Journal Article
Published: 01 April 1984
American Mineralogist (1984) 69 (3-4): 283–291.
...Heather E. Jamieson; Peter L. Roeder Abstract The equilibrium distribution of magnesium and ferrous iron between olivine and aluminate spinel, and between olivine and ferrite spinel, was determined at 1300°C in order to understand the relationship between these phases in mafic and ultramafic rocks...
Journal Article
Published: 01 November 2002
European Journal of Mineralogy (2002) 14 (6): 1095–1102.
... on site occupancies in ferri- and ferro-magnetic minerals. XMCD spectra derived from the Fe L 2,3 absorption edge of a series of synthetic spinel ferrites and natural magnetite were collected using synchrotron radiation and a 0.6 Tesla ‘flipper’ magnet. These spectra were used to assess their potential...
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Photomicrographs showing textural relationships of the assemblages in the C...
Published: 01 April 2005
F ig . 4. Photomicrographs showing textural relationships of the assemblages in the C2 unit. a) Mn–Zn-rich ferrite spinel embedded in massive granoblastic garnet and interstitial manganoan calcite (sample G38–1080). b) Banded garnet – clinopyroxene – spinel rock composed of layers of massive
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REPRESENTATIVE COMPOSITIONS OF <span class="search-highlight">FERRITE</span> <span class="search-highlight">SPINEL</span>
Published: 01 April 2005
TABLE 3. REPRESENTATIVE COMPOSITIONS OF FERRITE SPINEL
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Composition of <span class="search-highlight">ferrite</span> <span class="search-highlight">spinel</span> in the C2 unit. The stippled field correspond...
Published: 01 April 2005
F ig . 8. Composition of ferrite spinel in the C2 unit. The stippled field corresponds to the composition of franklinite-rich spinel reported in the literature. Data from Frondel & Klein (1965) , Johnson et al. (1990) , and Holtstam (2002) .
Journal Article
Published: 01 April 2005
The Canadian Mineralogist (2005) 43 (2): 585–599.
...F ig . 4. Photomicrographs showing textural relationships of the assemblages in the C2 unit. a) Mn–Zn-rich ferrite spinel embedded in massive granoblastic garnet and interstitial manganoan calcite (sample G38–1080). b) Banded garnet – clinopyroxene – spinel rock composed of layers of massive...
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The structure of a <span class="search-highlight">ferrite</span> <span class="search-highlight">spinel</span> showing the octahedral sites (small black...
Published: 01 November 2002
Fig. 1. The structure of a ferrite spinel showing the octahedral sites (small black spheres) and tetrahedral sites (small grey spheres). Oxygen is represented by large light grey spheres. (structure created using the programs Cerius 2 and Weblab Life, Molecular Simulations Inc.)
Journal Article
Published: 01 August 2017
Mineralogical Magazine (2017) 81 (4): 857–872.
... defined XMCD site specific peaks found in the ferrite spinel, magnetite. The Fe L 2,3 X-ray absorption spectra and XMCD spectra of the greigite reflect and reveal the high conductivity of greigite and the very strong covalency of the Fe–S bonding. The electron hopping between Fe 3+ and Fe 2+ on octahedral...
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Phase composition in the system FeO-FeO 1.5 -TiO 2  (mol%). The horizontal ...
Published: 01 May 2006
on the basis of a spinel formula unit (4 O atoms). Ideal phase compositions (filled triangles); titanium-rich ferrite spinel compositions calculated from XMCD data for samples T 203, SA 637, and SA 620, this work (gray squares); titanium-rich ferrite spinel compositions calculated on a basis of 4 O atoms and 3
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a) Clinopyroxene-melilite rock with druse vug (type A); b) melilite rich B-...
Published: 01 July 2005
of A-type rock (sample Ze8): darker prismatic mineral - clinopyroxene, lighter square-shaped crystals - melilite, opaque - magnesioferrite, light-grey - aragonite, colourless - cavities; f) photomicrograph of thin section of B-type rock. Transparent - melilite + Ca 2 SiO 5 , opaque - calcium ferrites
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Tetrahedral Fe 3+  vs.  tetrahedral Zn content of Mg-Zn-bearing <span class="search-highlight">ferrite</span> spi...
Published: 01 March 2001
Fig. 3. Tetrahedral Fe 3+ vs. tetrahedral Zn content of Mg-Zn-bearing ferrite spinels. Full diamond: MgF1a/6a sample; full square: Frk1a/d sample; open squares: literature data from Konakhovich & Saksonov (1963) , König & Chol (1968) , Rüegsegger et al. , (1970) , Sawicki (1974
Journal Article
Published: 01 July 2008
American Mineralogist (2008) 93 (7): 1119–1132.
... are often expensive to synthesize. In this study, the Fe 3+ -reducing bacteria Geobacter sulfurreducens and Shewanella oneidensis were used to synthesize spinel ferrite nanoparticles of the general chemical formula M x Fe 3– x O 4 , where M is either Co, Ni, Mn, Zn, or a combination of Mn and Zn...
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The experimentally derived XMCD spectra of mixed cation (Co, Ni, Zn and Mg)...
Published: 01 November 2002
Fig. 8. The experimentally derived XMCD spectra of mixed cation (Co, Ni, Zn and Mg) spinel ferrites. The theoretical XMCD spectrum for Fe 3 O 4 is also shown and the compositions of the spinel ferrites are shown in Table 1 .
Journal Article
Published: 01 May 2015
American Mineralogist (2015) 100 (5-6): 1257–1264.
... 1987 ; Haas 2003 ). The electrical conductivity mechanism of spinel ferrites containing Fe 2+ ions is explained by the electron hopping effect between Fe 2+ and Fe 3+ ions in octahedral sites ( Russo and Salahub 2000 ). Cation distribution between tetrahedral (A) and octahedral (B) sites...
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Journal Article
Published: 01 July 2005
European Journal of Mineralogy (2005) 17 (4): 623–633.
... of A-type rock (sample Ze8): darker prismatic mineral - clinopyroxene, lighter square-shaped crystals - melilite, opaque - magnesioferrite, light-grey - aragonite, colourless - cavities; f) photomicrograph of thin section of B-type rock. Transparent - melilite + Ca 2 SiO 5 , opaque - calcium ferrites...
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Journal Article
Published: 01 February 2017
American Mineralogist (2017) 102 (2): 327–332.
...(2) peak, the others show a character resembling the E g peaks noticed by D’Ippolito et al. (2015) and suggesting a certain degree of inversion. It is not possible to decipher if these natural spinels are chromate, aluminate or ferrite spinels by means of the E g mode as suggested by D’Ippolito...
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Journal Article
Published: 01 May 2018
European Journal of Mineralogy (2018) 30 (3): 559–567.
...–gehlenite hornfels of the Hatrurim Complex, Palestinian Autonomy. Both ferrites are characterized by a modular structure composed of 5-layered spinel ( S ) blocks interstratified with R -blocks. The R -modules of K-ferrite are of the β-alumina type whereas those in Ba-ferrite are of the magnetoplumbite type...
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