The Experts below are selected from a list of 273 Experts worldwide ranked by ideXlab platform
V A Semionkin - One of the best experts on this subject based on the ideXlab platform.
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study of rhabdite Iron nickel phosphide microcrystals extracted from sikhote alin Iron Meteorite by magnetization measurements and mossbauer spectroscopy
Materials Chemistry and Physics, 2011Co-Authors: M I Oshtrakh, V I Grokhovsky, Yu M Larionov, V A SemionkinAbstract:Abstract Study of rhabdite (Iron nickel phosphide) microcrystals extracted from Sikhote–Alin Iron Meteorite was made using scanning electron microscopy, X-ray diffraction, magnetic measurements and Mossbauer spectroscopy with a high velocity resolution at various temperatures. The Curie temperature for Iron nickel phosphide microcrystals was evaluated in the range of 345–355 K. On the basis of Mossbauer data the temperature dependences of magnetic hyperfine fields for Fe atoms in the M1, M2 and M3 sites of rhabdite were shown as well as Fe and Ni occupancies of these sites were evaluated.
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temperature dependent high velocity resolution mossbauer spectroscopic study of Iron nickel phosphide microcrystals rhabdites extracted from sikhote alin Iron Meteorite
Journal of Alloys and Compounds, 2011Co-Authors: M I Oshtrakh, V I Grokhovsky, Yu M Larionov, V A SemionkinAbstract:Abstract Iron nickel phosphide microcrystals (rhabdites) extracted from Sikhote-Alin Iron Meteorite fragment were studied using Mossbauer spectroscopy with a high velocity resolution at various temperatures. Mossbauer spectra of rhabdites demonstrated superparamagnetic behavior. Low temperature rhabdite spectra were fitted using a model with six magnetic sextets two pairs of which were related to crystallographically non-equivalent sites M1, M2 and M3 occupied by Fe and Ni atoms in different ways. Temperature dependencies of correspondent magnetic hyperfine fields were evaluated. On the basis of relative areas of spectral components and results of rhabdite chemical analysis the average numbers of Fe and Ni atoms occupied the M1, M2 and M3 sites, respectively, were evaluated.
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Iron nickel alloy from Iron Meteorite chinga studied by mossbauer spectroscopy with high velocity resolution
Hyperfine Interactions, 2009Co-Authors: M I Oshtrakh, V I Grokhovsky, V A Semionkin, N V Abramova, O B MilderAbstract:Study of Iron–nickel alloy from Iron Meteorite Chinga using Mossbauer spectroscopy with improved velocity resolution (measurement and presentation in 4,096 channels) revealed six magnetic components which may be related to various α-Fe(Ni, Co) and γ-Fe(Ni, Co) phases while previous study with low velocity resolution (in 512 channels) revealed only three magnetic components. This new result was in agreement with the scanning electron microscopy study.
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study of Iron Meteorite sikhote alin and extracted Iron nickel phosphides using mossbauer spectroscopy with high velocity resolution
Hyperfine Interactions, 2008Co-Authors: M I Oshtrakh, V I Grokhovsky, Yu M Larionov, V A SemionkinAbstract:Comparative study of schreibersite and rhabdite extracted from Sikhote–Alin (IIAB) Iron Meteorite using Mossbauer spectroscopy, X-ray diffraction and magnetic measurements was carried out. Mossbauer spectra of bulk Meteorite sample and extracted phosphides were recorded in 4,096 channels and then presented in 1,024 channels. Differences of the unit cell structure, the Fe, Ni and Co content, the room temperature Mossbauer spectra and Curie temperature for rhabdite and schreibersite were found.
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mossbauer spectroscopy of Iron Meteorite dronino and products of its corrosion
Hyperfine Interactions, 2006Co-Authors: V I Grokhovsky, M I Oshtrakh, O B Milder, V A SemionkinAbstract:The results of the first study of Iron Meteorite Dronino and products of its corrosion by Mossbauer spectroscopy are presented. Mossbauer parameters for Iron phase, sulfide inclusions, products of terrestrial corrosion and Iron oxides in concretion are determined and analyzed.
M I Oshtrakh - One of the best experts on this subject based on the ideXlab platform.
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Iron sulfide troilite inclusion extracted from sikhote alin Iron Meteorite composition structure and magnetic properties
Materials Chemistry and Physics, 2016Co-Authors: M I Oshtrakh, V I Grokhovsky, Zoltan Klencsar, E V Petrova, A V Chukin, A K Shtoltz, A A Maksimova, I Felner, E Kuzmann, Z HomonnayAbstract:Abstract Iron sulfide (troilite) inclusion extracted from Sikhote-Alin IIAB Iron Meteorite was examined for its composition, structure and magnetic properties by means of several complementary analytical techniques such as: powder X-ray diffractometry, scanning electron microscopy combined with energy-dispersive X-ray spectroscopy, magnetization measurements, ferromagnetic resonance spectroscopy and 57 Fe Mossbauer spectroscopy with a high velocity resolution. The applied techniques consistently indicated the presence of daubreelite (FeCr 2 S 4 ) as a minority phase beside troilite proper (FeS). As revealed by 57 Fe Mossbauer spectroscopy, the Fe atoms in troilite were in different microenvIronments associated with either the ideal FeS structure or that of a slightly Iron deficient Fe 1– x S. Phase transitions of troilite were detected above room temperature by ferromagnetic resonance spectroscopy. A novel analysis of 295 and 90 K 57 Fe Mossbauer spectra was carried out and the hyperfine parameters associated with the ideal structure of troilite were determined by considering the orientation of the hyperfine magnetic field in the eigensystem of the electric field gradient at the 57 Fe nucleus.
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study of rhabdite Iron nickel phosphide microcrystals extracted from sikhote alin Iron Meteorite by magnetization measurements and mossbauer spectroscopy
Materials Chemistry and Physics, 2011Co-Authors: M I Oshtrakh, V I Grokhovsky, Yu M Larionov, V A SemionkinAbstract:Abstract Study of rhabdite (Iron nickel phosphide) microcrystals extracted from Sikhote–Alin Iron Meteorite was made using scanning electron microscopy, X-ray diffraction, magnetic measurements and Mossbauer spectroscopy with a high velocity resolution at various temperatures. The Curie temperature for Iron nickel phosphide microcrystals was evaluated in the range of 345–355 K. On the basis of Mossbauer data the temperature dependences of magnetic hyperfine fields for Fe atoms in the M1, M2 and M3 sites of rhabdite were shown as well as Fe and Ni occupancies of these sites were evaluated.
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temperature dependent high velocity resolution mossbauer spectroscopic study of Iron nickel phosphide microcrystals rhabdites extracted from sikhote alin Iron Meteorite
Journal of Alloys and Compounds, 2011Co-Authors: M I Oshtrakh, V I Grokhovsky, Yu M Larionov, V A SemionkinAbstract:Abstract Iron nickel phosphide microcrystals (rhabdites) extracted from Sikhote-Alin Iron Meteorite fragment were studied using Mossbauer spectroscopy with a high velocity resolution at various temperatures. Mossbauer spectra of rhabdites demonstrated superparamagnetic behavior. Low temperature rhabdite spectra were fitted using a model with six magnetic sextets two pairs of which were related to crystallographically non-equivalent sites M1, M2 and M3 occupied by Fe and Ni atoms in different ways. Temperature dependencies of correspondent magnetic hyperfine fields were evaluated. On the basis of relative areas of spectral components and results of rhabdite chemical analysis the average numbers of Fe and Ni atoms occupied the M1, M2 and M3 sites, respectively, were evaluated.
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Iron nickel alloy from Iron Meteorite chinga studied by mossbauer spectroscopy with high velocity resolution
Hyperfine Interactions, 2009Co-Authors: M I Oshtrakh, V I Grokhovsky, V A Semionkin, N V Abramova, O B MilderAbstract:Study of Iron–nickel alloy from Iron Meteorite Chinga using Mossbauer spectroscopy with improved velocity resolution (measurement and presentation in 4,096 channels) revealed six magnetic components which may be related to various α-Fe(Ni, Co) and γ-Fe(Ni, Co) phases while previous study with low velocity resolution (in 512 channels) revealed only three magnetic components. This new result was in agreement with the scanning electron microscopy study.
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study of Iron Meteorite sikhote alin and extracted Iron nickel phosphides using mossbauer spectroscopy with high velocity resolution
Hyperfine Interactions, 2008Co-Authors: M I Oshtrakh, V I Grokhovsky, Yu M Larionov, V A SemionkinAbstract:Comparative study of schreibersite and rhabdite extracted from Sikhote–Alin (IIAB) Iron Meteorite using Mossbauer spectroscopy, X-ray diffraction and magnetic measurements was carried out. Mossbauer spectra of bulk Meteorite sample and extracted phosphides were recorded in 4,096 channels and then presented in 1,024 channels. Differences of the unit cell structure, the Fe, Ni and Co content, the room temperature Mossbauer spectra and Curie temperature for rhabdite and schreibersite were found.
Alan E. Rubin - One of the best experts on this subject based on the ideXlab platform.
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edscottite fe5c2 a new Iron carbide mineral from the ni rich wedderburn iab Iron Meteorite
American Mineralogist, 2019Co-Authors: Alan E. RubinAbstract:Edscottite (IMA 2018-086a), Fe_5C_2, is a new Iron carbide mineral that occurs with low-Ni Iron (kamacite), taenite, nickelphosphide (Ni-dominant schreibersite), and minor cohenite in the Wedder-burn Iron Meteorite, a Ni-rich member of the group IAB complex. The mean chemical composition of edscottite determined by electron probe microanalysis, is (wt%) Fe 87.01, Ni 4.37, Co 0.82, C 7.90, total 100.10, yielding an empirical formula of (Fe_(4.73)Ni_(0.23)Co_(0.04))C_(2.00). The end-member formula is Fe_5C_2. Electron backscatter diffraction shows that edscottite has the C2/c Pd_5B_2-type structure of the synthetic phase called Hagg-carbide, χ-Fe_5C_2, which has a = 11.57 A, b= 4.57 A, c = 5.06 A, β = 97.7 °, V = 265.1 A^3, and Z = 4. The calculated density using the measured composition is 7.62 g/cm^3. Like the other two carbides found in Iron Meteorites, cohenite (Fe_3C) and haxonite (Fe_(23)C_6), edscottite forms in kamacite, but unlike these two carbides, it forms laths, possibly due to very rapid growth after supersaturation of carbon. Haxonite (which typically forms in carbide-bearing, Ni-rich members of the IAB complex) has not been observed in Wedderburn. Formation of edscottite rather than haxonite may have resulted from a lower C concentration in Wedderburn and hence a lower growth temperature. The new mineral is named in honor of Edward (Ed) R.D. Scott, a pioneering cosmochemist at the University of Hawai‘i at Manoa, for his seminal contributions to research on Meteorites.
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joegoldsteinite a new sulfide mineral mncr2s4 from the social circle iva Iron Meteorite
American Mineralogist, 2016Co-Authors: J Isa, Alan E. RubinAbstract:Joegoldsteinite, a new sulfide mineral of end-member formula MnCr_2S_4, was discovered in the Social Circle IVA Iron Meteorite. It is a thiospinel, the Mn analog of daubreelite (Fe^(2+)Cr_2S_4), and a new member of the linnaeite group. Tiny grains of joegoldsteinite were also identified in the Indarch EH4 enstatite chondrite. The chemical composition of the Social Circle sample determined by electron microprobe is (wt%) S 44.3, Cr 36.2, Mn 15.8, Fe 4.5, Ni 0.09, Cu 0.08, total 101.0, giving rise to an empirical formula of (Mn_(0.82)Fe_(0.23))Cr_(1.99)S_(3.95). The crystal structure, determined by electron backscattered diffraction, is a Fd3m spinel-type structure with a = 10.11 A, V = 1033.4 A^3, and Z = 8.
V I Grokhovsky - One of the best experts on this subject based on the ideXlab platform.
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Iron sulfide troilite inclusion extracted from sikhote alin Iron Meteorite composition structure and magnetic properties
Materials Chemistry and Physics, 2016Co-Authors: M I Oshtrakh, V I Grokhovsky, Zoltan Klencsar, E V Petrova, A V Chukin, A K Shtoltz, A A Maksimova, I Felner, E Kuzmann, Z HomonnayAbstract:Abstract Iron sulfide (troilite) inclusion extracted from Sikhote-Alin IIAB Iron Meteorite was examined for its composition, structure and magnetic properties by means of several complementary analytical techniques such as: powder X-ray diffractometry, scanning electron microscopy combined with energy-dispersive X-ray spectroscopy, magnetization measurements, ferromagnetic resonance spectroscopy and 57 Fe Mossbauer spectroscopy with a high velocity resolution. The applied techniques consistently indicated the presence of daubreelite (FeCr 2 S 4 ) as a minority phase beside troilite proper (FeS). As revealed by 57 Fe Mossbauer spectroscopy, the Fe atoms in troilite were in different microenvIronments associated with either the ideal FeS structure or that of a slightly Iron deficient Fe 1– x S. Phase transitions of troilite were detected above room temperature by ferromagnetic resonance spectroscopy. A novel analysis of 295 and 90 K 57 Fe Mossbauer spectra was carried out and the hyperfine parameters associated with the ideal structure of troilite were determined by considering the orientation of the hyperfine magnetic field in the eigensystem of the electric field gradient at the 57 Fe nucleus.
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study of rhabdite Iron nickel phosphide microcrystals extracted from sikhote alin Iron Meteorite by magnetization measurements and mossbauer spectroscopy
Materials Chemistry and Physics, 2011Co-Authors: M I Oshtrakh, V I Grokhovsky, Yu M Larionov, V A SemionkinAbstract:Abstract Study of rhabdite (Iron nickel phosphide) microcrystals extracted from Sikhote–Alin Iron Meteorite was made using scanning electron microscopy, X-ray diffraction, magnetic measurements and Mossbauer spectroscopy with a high velocity resolution at various temperatures. The Curie temperature for Iron nickel phosphide microcrystals was evaluated in the range of 345–355 K. On the basis of Mossbauer data the temperature dependences of magnetic hyperfine fields for Fe atoms in the M1, M2 and M3 sites of rhabdite were shown as well as Fe and Ni occupancies of these sites were evaluated.
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temperature dependent high velocity resolution mossbauer spectroscopic study of Iron nickel phosphide microcrystals rhabdites extracted from sikhote alin Iron Meteorite
Journal of Alloys and Compounds, 2011Co-Authors: M I Oshtrakh, V I Grokhovsky, Yu M Larionov, V A SemionkinAbstract:Abstract Iron nickel phosphide microcrystals (rhabdites) extracted from Sikhote-Alin Iron Meteorite fragment were studied using Mossbauer spectroscopy with a high velocity resolution at various temperatures. Mossbauer spectra of rhabdites demonstrated superparamagnetic behavior. Low temperature rhabdite spectra were fitted using a model with six magnetic sextets two pairs of which were related to crystallographically non-equivalent sites M1, M2 and M3 occupied by Fe and Ni atoms in different ways. Temperature dependencies of correspondent magnetic hyperfine fields were evaluated. On the basis of relative areas of spectral components and results of rhabdite chemical analysis the average numbers of Fe and Ni atoms occupied the M1, M2 and M3 sites, respectively, were evaluated.
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Iron nickel alloy from Iron Meteorite chinga studied by mossbauer spectroscopy with high velocity resolution
Hyperfine Interactions, 2009Co-Authors: M I Oshtrakh, V I Grokhovsky, V A Semionkin, N V Abramova, O B MilderAbstract:Study of Iron–nickel alloy from Iron Meteorite Chinga using Mossbauer spectroscopy with improved velocity resolution (measurement and presentation in 4,096 channels) revealed six magnetic components which may be related to various α-Fe(Ni, Co) and γ-Fe(Ni, Co) phases while previous study with low velocity resolution (in 512 channels) revealed only three magnetic components. This new result was in agreement with the scanning electron microscopy study.
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study of Iron Meteorite sikhote alin and extracted Iron nickel phosphides using mossbauer spectroscopy with high velocity resolution
Hyperfine Interactions, 2008Co-Authors: M I Oshtrakh, V I Grokhovsky, Yu M Larionov, V A SemionkinAbstract:Comparative study of schreibersite and rhabdite extracted from Sikhote–Alin (IIAB) Iron Meteorite using Mossbauer spectroscopy, X-ray diffraction and magnetic measurements was carried out. Mossbauer spectra of bulk Meteorite sample and extracted phosphides were recorded in 4,096 channels and then presented in 1,024 channels. Differences of the unit cell structure, the Fe, Ni and Co content, the room temperature Mossbauer spectra and Curie temperature for rhabdite and schreibersite were found.
David N. Seidman - One of the best experts on this subject based on the ideXlab platform.
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atom probe tomography and transmission electron microscopy of the kamacite taenite interface in the fast cooled bristol iva Iron Meteorite
Meteoritics & Planetary Science, 2017Co-Authors: S. S. Rout, Andrew M Davis, Philipp R. Heck, Dieter Isheim, Thomas Stephan, Nestor J. Zaluzec, Dean J. Miller, David N. SeidmanAbstract:We report the first combined atom-probe tomography (APT) and transmission electron microscopy (TEM) study of a kamacite–tetrataenite (K–T) interface region within an Iron Meteorite, Bristol (IVA). Ten APT nanotips were prepared from the K–T interface with focused ion beam scanning electron microscopy (FIB-SEM) and then studied using TEM followed by APT. Near the K-T interface, we found 3.8 ± 0.5 wt% Ni in kamacite and 53.4 ± 0.5 wt% Ni in tetrataenite. High-Ni precipitate regions of the cloudy zone (CZ) have 50.4 ± 0.8 wt% Ni. A region near the CZ and martensite interface has <10 nm sized Ni-rich precipitates with 38.4 ± 0.7 wt% Ni present within a low-Ni matrix having 25.5 ± 0.6 wt% Ni. We found that Cu is predominantly concentrated in tetrataenite, whereas Co, P, and Cr are concentrated in kamacite. Phosphorus is preferentially concentrated along the K-T interface. This study is the first precise measurement of the phase composition at high spatial resolution and in 3-D of the K-T interface region in a IVA Iron Meteorite and furthers our knowledge of the phase composition changes in a fast-cooled Iron Meteorite below 400 °C. We demonstrate that APT in conjunction with TEM is a useful approach to study the major, minor, and trace elemental composition of nanoscale features within fast-cooled Iron Meteorites.
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Atom-probe tomography and transmission electron microscopy of the kamacite–taenite interface in the fast-cooled Bristol IVA Iron Meteorite
Meteoritics & Planetary Science, 2017Co-Authors: S. S. Rout, Andrew M Davis, Philipp R. Heck, Dieter Isheim, Thomas Stephan, Nestor J. Zaluzec, Dean J. Miller, David N. SeidmanAbstract:We report the first combined atom-probe tomography (APT) and transmission electron microscopy (TEM) study of a kamacite–tetrataenite (K–T) interface region within an Iron Meteorite, Bristol (IVA). Ten APT nanotips were prepared from the K–T interface with focused ion beam scanning electron microscopy (FIB-SEM) and then studied using TEM followed by APT. Near the K-T interface, we found 3.8 ± 0.5 wt% Ni in kamacite and 53.4 ± 0.5 wt% Ni in tetrataenite. High-Ni precipitate regions of the cloudy zone (CZ) have 50.4 ± 0.8 wt% Ni. A region near the CZ and martensite interface has
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Atom‐probe tomography and transmission electron microscopy of the kamacite–taenite interface in the fast‐cooled Bristol IVA Iron Meteorite
Meteoritics & Planetary Science, 2017Co-Authors: S. S. Rout, Andrew M Davis, Philipp R. Heck, Dieter Isheim, Thomas Stephan, Nestor J. Zaluzec, Dean J. Miller, David N. SeidmanAbstract:We report the first combined atom-probe tomography (APT) and transmission electron microscopy (TEM) study of a kamacite–tetrataenite (K–T) interface region within an Iron Meteorite, Bristol (IVA). Ten APT nanotips were prepared from the K–T interface with focused ion beam scanning electron microscopy (FIB-SEM) and then studied using TEM followed by APT. Near the K-T interface, we found 3.8 ± 0.5 wt% Ni in kamacite and 53.4 ± 0.5 wt% Ni in tetrataenite. High-Ni precipitate regions of the cloudy zone (CZ) have 50.4 ± 0.8 wt% Ni. A region near the CZ and martensite interface has
