Plasma synthesis, Mössbauer spectroscopy and X-ray diffraction studies of nanosized iron oxides

2010 ◽  
Vol 198 (1-3) ◽  
pp. 265-272 ◽  
Author(s):  
Daniela Paneva ◽  
Katerina Zaharieva ◽  
Janis Grabis ◽  
Ivan Mitov ◽  
Gheorghi Vissokov
Keyword(s):  
Mössbauer Spectroscopy ◽  
Iron Oxides ◽  
Mossbauer Spectroscopy ◽  
Plasma Synthesis ◽  
X Ray Diffraction ◽  
X Ray ◽  
Mößbauer Spectroscopy ◽  
Nanosized Iron

scholarly journals Coffee plantation soil characterization using a multi-method approach near the Volcano Nevado del Ruiz, Colombian Central Cordillera

2021 ◽  
Vol 25 (3) ◽  
pp. 263-273
Author(s):  
Brahiam Hincapié ◽  
Alexander Cortés-Soto ◽  
Mauricio A Bermudez ◽  
Santiago Yepez ◽  
Juan Sebastián Trujillo-Hernández ◽  
...  
Keyword(s):  
Mössbauer Spectroscopy ◽  
Iron Oxides ◽  
Mossbauer Spectroscopy ◽  
X Ray Diffraction ◽  
X Ray ◽  
Mößbauer Spectroscopy ◽  
Mineral Phases ◽  
Multi Method Approach ◽  
Sentinel 2A ◽  
Spectral Imager

The presence of iron oxides may provide a sensitive indicator of the effects of cropping practices on coffee plantations. Authors characterized the mineral phases present in soil A horizons at three different farms located in the Department of Tolima within the regions of Líbano and Villahermosa. Our analysis includes X-ray diffraction, Mössbauer spectroscopy, and remote sensing to discriminate the distribution of the different magnetic mineral phases. X-ray diffraction was used to identify the mineralogical properties of iron oxide such as hematite, goethite, and ferrihydrite (Fh), as well as tectosilicate minerals such as albite and sanidine. Mössbauer spectroscopy results for samples taken at room temperature indicate the presence of Fe2+ and Fe3+ mineral phases, which possibly correspond to ilmenite or magnetite. Finally, Sentinel-2A multi-spectral imager (MSI) data was used to map the distribution of iron oxides and study the influence of their distribution throughout the study area. A high correlation between Mössbauer spectroscopy and Sentinel-2A MSI data exists throughout the study area. The results suggest that farms close to the main Nevado del Ruíz Volcano have a more significant mineralogical variability. In contrast, more distant farms are characterized by soils with more iron oxides, the product of weathering, erosion, and human activities.

Iron oxide mineralogy of a hydrothermal assemblage on Santorini Island, Aegean Sea

1982 ◽  
Vol 46 (338) ◽  
pp. 89-93 ◽  
Author(s):  
Enver Murad
Keyword(s):  
Mössbauer Spectroscopy ◽  
Iron Oxide ◽  
Iron Oxides ◽  
Mossbauer Spectroscopy ◽  
Aegean Sea ◽  
Hydrothermal Fluids ◽  
X Ray Diffraction ◽  
X Ray ◽  
Mößbauer Spectroscopy ◽  
Basement Rocks

AbstractBasement rocks of Santorini have been locally impregnated by iron oxides and other minerals. The hydrothermal fluids which caused the mineralization have extensively altered the impregnated rocks, but left granditic garnets in these unaffected.Mössbauer spectroscopy and differential X-ray diffraction show that the iron oxides present are goethite and hematite in a ratio of about 2 : 1. The presence of hematite indicates that these minerals formed, directly from a hydrothermal phase, at higher temperatures than the recent submarine iron oxide deposits of Santorini, which contain no hematite.

Hydrolysis of FeIII solution to hydrous iron oxides

Soil Research ◽  
1989 ◽  
Vol 27 (1) ◽  
pp. 103 ◽  
Author(s):  
DG Lewis ◽  
CM Cardile
Keyword(s):  
Mössbauer Spectroscopy ◽  
Iron Oxides ◽  
Mossbauer Spectroscopy ◽  
Ammonium Oxalate ◽  
Magnetic Ordering ◽  
Low Ph ◽  
Ferric Nitrate ◽  
X Ray Diffraction ◽  
X Ray ◽  
Mößbauer Spectroscopy

A range of hydrous iron oxides was prepared from ferric nitrate solutions by varying the rate and manner of hydrolysis. The properties of the resultant products were determined by using various techniques including size fractionation with Amicon Diafilters, rate and extent of dissolution in acid ammonium oxalate solution, X-ray diffraction and Mossbauer spectroscopy. The variation in properties is interpreted in terms of the conditions under which the various materials had been formed. The products of spontaneous hydrolysis at low pH and low FeIII concentration had properties distinctly different from those samples in which hydrolysis was induced rapidly by addition of alkali. The low-pH products were far more resistant to dissolution in acid ammonium oxalate and were relatively well ordered as determined by X-ray diffraction and Mossbauer spectroscopy at 77 K. The crystallographic and magnetic ordering of the rapidly formed phase is normally very limited, but these properties were increased significantly if formation occurred in the presence of low-pH polymeric material which may act as a template for freshly precipitating oxides.

Nature and mechanism of ilmenite alteration: a Mössbauer and X-ray diffraction study of oxidized ilmenite from the Beja-Acebuches Ophiolite Complex (SE Portugal)

2002 ◽  
Vol 66 (3) ◽  
pp. 421-430 ◽  
Author(s):  
J. C. Waerenborgh ◽  
J. Figueiras ◽  
A. Mateus ◽  
M. Gonçalves
Keyword(s):  
Mössbauer Spectroscopy ◽  
Mossbauer Spectroscopy ◽  
X Ray Diffraction ◽  
Ophiolite Complex ◽  
Cation Site ◽  
X Ray ◽  
Mößbauer Spectroscopy ◽  
Ilmenite Structure ◽  
Optical Evidence ◽  
Excess Fe

AbstractIlmenites from the least-altered rocks of the Beja-Acebuches Ophiolite Complex (SE Portugal), with low Ti values and excess Fe, despite rare optical evidence of hematite exsolution, were studied by 57Fe Mössbauer spectroscopy and X-ray diffraction. According to single-crystal XRD the sequence of alternate layers characteristic of the ideal ilmenite structure is preserved, the excess Fe being accommodated in the Ti layers. No superparamagnetic oxides were detected by 57Fe Mössbauer spectroscopy. The typical spectra of bulk αFe2O3 and of Fe3+-containing ilmenite, in the paramagnetic state above 49 K and magnetically ordered at 6 K, are observed. The average degree of oxidation of the ilmenites, estimated from the chemical analysis assuming ideally stoichiometric full cation site occupancies, is also confirmed by 57Fe Mössbauer data. Since our crystal chemistry study gave no evidence of crypto-exsolution textures within the ilmenite with the observed compositions, fast cooling from magmatic temperatures and decomposition of ilmenite in supergene conditions is suggested.

A Study of Aluminum-Substituted Iron Dextran Complexes by Mössbauer Spectroscopy and X-ray Diffraction

2001 ◽  
Vol 13 (1) ◽  
pp. 136-140 ◽  
Author(s):  
Tianrong Cheng ◽  
Robert Bereman ◽  
Eddy De Grave ◽  
Larry H. Bowen
Keyword(s):  
Mössbauer Spectroscopy ◽  
Mossbauer Spectroscopy ◽  
Iron Dextran ◽  
X Ray Diffraction ◽  
X Ray ◽  
Mößbauer Spectroscopy

Microstructure Evolution and Mossbauer Spectroscopy Research of Nanostructured Ni3 Fe Intermetallic

2021 ◽  
Vol 32 ◽  
pp. 1-13
Author(s):  
Amel Kaibi ◽  
Abderrahim Guittoum ◽  
Nassim Souami ◽  
Mohamed Kechouane
Keyword(s):  
Magnetic Field ◽  
Mössbauer Spectroscopy ◽  
Mössbauer Spectra ◽  
Milling Time ◽  
Mossbauer Spectroscopy ◽  
Hyperfine Magnetic Field ◽  
X Ray Diffraction ◽  
X Ray ◽  
Mossbauer Spectra ◽  
Mößbauer Spectroscopy

Nanocrystalline Ni75Fe25 (Ni3Fe) powders were prepared by mechanical alloying process using a vario-planetary high-energy ball mill. The intermetallic Ni3Fe formation and different physical properties were investigated, as a function of milling time, t, (in the range 6 to 96 h range), using X-Ray Diffraction (XRD) and Mössbauer Spectroscopy techniques. X-ray diffraction were performed on the samples to understand the structural characteristics and get information about elements and phases present in the powder after different time of milling. The refinement of XRD spectra revealed the complete formation of fcc Ni (Fe) disordered solid solution after 24 h of milling time, the Fe and Ni elemental distributions are closely correlated. With increasing the milling time, the lattice parameter increases and the grains size decreases. The Mössbauer experiments were performed on the powders in order to follow the formation of Ni3Fe compound as a function of milling time. From the adjustment of Mössbauer spectra, we extracted the hyperfine parameters. The evolution of hyperfine magnetic field shows that the magnetic disordered Ni3Fe phase starts to form from 6 h of milling time and grow in intensity with milling time. For the milling time more than 24 h, only the Ni3Fe disordered phase is present with a mean hyperfine magnetic field of about 29.5 T. The interpretation of the Mossbauer spectra confirmed the results obtained by XRD.

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