134 research outputs found
Effect of time and storing conditions on iron forms in ferrous gluconate and Ascofer
Antianemic medicament Ascofer and ferrous gluconate, its basic iron bearing
ingredient, were studied with the use of Mossbauer spectroscopy. Room
temperature spectra gave a clear evidence that two phases of iron were present
viz. ferrous (Fe2+) as a major one with a contribution of 85+-5%, and ferric
(Fe3+) whose contribution was found to be 15+-5%. However, the actual values of
the contributions of the two kind of the iron ions in Ascofer depend on
sample's age: the abundance of Fe2+ ions increases with time by 10% after 51
months, while that of Fe3+ decreases by the same amount. This means that an
internal reduction of Fe3+ ions takes place. Ferrous ions were shown to occupy
at least two different sites. In Ascofer, the relative abundance of the two
sites does not depend on the age of sample, while in the gluconate the
population of site 1 increases and that of site 2 decreases with the age of the
sample.Comment: 14 pages, 13 figure
Evaluation of the Debye temperature for iron cores in human liver ferritin and its pharmaceutical analogue Ferrum Lek using Mossbauer spectroscopy
An iron polymaltose complex Ferrum Lek used as antianemic drug and considered
as a ferritin analogue and human liver ferritin were investigated in the
temperature range from 295K to 90K by means of 57Fe Mossbauer spectroscopy with
a high velocity resolution i.e. in 4096 channels. The Debye temperatures equal
to 502K for Ferrum Lek and to 461K for human liver ferritin were determined
from the temperature dependence of the center shift obtained using two
different fitting procedures.Comment: 13 pages, 5 figure
Iron environment non-equivalence in both octahedral and tetrahedral sites in NiFe2O4 nanoparticles: study using Mössbauer spectroscopy with a high velocity resolution
Mössbauer spectrum of NiFe2O4 nanoparticles was measured at room temperature in 4096 channels. This spectrum was fitted using various models, consisting of different numbers of magnetic sextets from two to twelve. Non-equivalence of the 57Fe microenvironments due to various probabilities of different Ni2+ numbers surrounding the octahedral and tetrahedral sites was evaluated and at least 5 different microenvironments were shown for both sites. The fit of the Mössbauer spectrum of NiFe 2O4 nanoparticles using ten sextets showed some similarities in the histograms of relative areas of sextets and calculated probabilities of different Ni2+ numbers in local microenvironments. © 2012 American Institute of Physics
Study of olivines from Omolon and Seymchan meteorites using X-ray diffraction and Mössbauer spectroscopy with a high velocity resolution
Study of olivine from Omolon and Seymchan meteorites was performed using X-ray diffraction and Mössbauer spectroscopy with a high velocity resolution. X-ray diffraction patterns were measured at room temperature while Mössbauer spectra were measured at 295 and 90 K. The orthorhombic crystal lattice parameters were evaluated for olivine from Omolon and Seymchan. These parameters appeared to be different for olivines from both meteorites. Mössbauer spectral components related to 57Fe in crystallographically non-equivalent sites M1 and M2 in both olivines were determined and its Mössbauer hyperfine parameters were evaluated. Some differences in the tendencies of temperature dependence of spectral parameters and small variations of 57Fe quadrupole splitting in both M1 and M2 sites of olivines from Omolon and Seymchan were found. On the basis of Mössbauer parameters and chemical data, the temperatures of equilibrium cation distribution were evaluated for both olivines. © 2012 American Institute of Physics
Comparative study of nanosized iron cores in human liver ferritin and its pharmaceutically important models Maltofer® and Ferrum Lek using Mössbauer spectroscopy
Studies of human liver ferritin and its pharmaceutically important models Maltofer® and Ferrum Lek were carried out using Mössbauer spectroscopy with a high velocity resolution at 295 and 90 K and Mössbauer spectroscopy with a low velocity resolution at 40 and 20 K. The Mössbauer spectra fits using a multi-component model confirm the hypothesis of the complicated heterogeneous structure of nanosized iron cores in the investigated samples. © 2013 Allerton Press, Inc
Applications of mössbauer spectroscopy in meteoritical and planetary science, part i: Undifferentiated meteorites
Mössbauer (nuclear γ-resonance) spectroscopy is a powerful technique that is actively used in various fields, from physics and chemistry to biology and medicine. Rudolf L. Mössbauer, who observed nuclear γ-resonance and published his results in 1958, received a Nobel Prize in physics in 1961 for this discovery. The57 Fe is the most widely used nucleus in Mössbauer spectroscopy. Therefore, a large variety of compounds containing iron can be studied by Mössbauer spectroscopy. It is well known that planetary matter contains various iron-bearing phases and minerals. Therefore, the extraterrestrial material from different meteorites, asteroids, and planets can be studied using 57 Fe Mössbauer spectroscopy as additional powerful technique. Two parts of this review consider the results of more than 50 years of experience of Mössbauer spectroscopy applied for the studies of various meteorites, soils, and rocks from the Moon and recent investigation of the Mars surface using two rovers equipped with miniaturized Mössbauer spectrometers. Part I will discuss known results on Mössbauer spectroscopy of undifferentiated meteorites, which are the most primitive and formed with the solar system. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.This work was supported by the Ministry of Science and Higher Education of the Russian Federation, project № FEUZ‐2020‐0060. The Zavaritsky Institute of Geology and Geochemistry of the Ural Branch of the Russian Academy of Sciences is supported by the Ministry of Science and Higher Education of the Russian Federation, project № AAAA‐A19‐119071090011‐6 (A.A.M.)
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