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Properties of iron in various samples of biological tissues were analyzed from the point of view of demonstration of their magnetic properties and structural positions. 57Fe Mössbauer spectrometry in transmission mode was applied as a principal investigation tool. Absorption spectra were recorded directly from lyophilized tissues of human brain, human and horse spleen. Mössbauer measurements were performed at room temperature (∼300 K) and at the temperature of 4.2 K using liquid helium bath cryostat. Each spectrum obtained at room temperature exhibits doublet-like features, which indicated presence of very small non-magnetically ordered or superparamagnetic particles. Low-temperature Mössbauer spectra are superpositions of sextets and one doublet. Spectral parameters of the sextet-like components are similar to those for hematite, ferrihydrite or possibly magnetite. [ABSTRACT FROM AUTHOR]

Magnetic behavior of Fe51Co12Si16B8 Mo 5P8 metallic glass prepared by a melt spinning technique is studied by magnetic measurements and room temperature transmission Mössbauer spectrometry. Mössbauer spectra were evaluated by the Normos program using distributions of hyperfine magnetic fields, P(B). The resulting ribbons were inspected in the as-quenched state as well as after annealing at temperatures of 200-550 °C for 1 hour. In the low temperature region, i.e., below the onset of crystallization, structural relaxation phenomena were unveiled. The onset of crystallization as derived from DSC and from XRD measurements differs by ∼40 degrees. Traces of crystalline phases were observed by XRD after annealing at 525 °C while DSC gives T x1 = 566 °C. Mössbauer spectrometry exhibits presence of crystallites only after annealing at 550 °C. Standard deviation and the mean hyperfine magnetic field values of P(B) distributions obtained from Mössbauer spectrometry monotonically increase with temperature of annealing. They are attributed to the modification in the short range order of Fe atoms environments. [ABSTRACT FROM AUTHOR]

The long-term reliability of construction materials operating in nuclear facilities under harsh conditions such as intense irradiation, high temperature, and in the presence of corrosion agents is a serious technologic, economic, and environmental demand. In this work, we elucidate the structural features of advanced corrosion-resistant LC 200N steel. High Cr and N contents provide high hardness and wear resistance of this perspective material which can be considered for possible applications in nuclear installations. Structural arrangement was checked by scanning electron microscopy and transmission electron microscopy. Chemical composition was inspected by X-ray fluorescence technique, spark optical emission spectroscopy, and neutron activation analysis. Mössbauer spectrometry was chosen as the principal method of investigation. Conversion Electron Mössbauer Spectrometry and transmission techniques were applied. [ABSTRACT FROM AUTHOR]

Combination of short data acquisition time and local investigation of a solid state through hyperfine parameters makes nuclear forward scattering (NFS) a unique experimental technique for investigation of fast processes. However, the total number of acquired NFS time spectra may be very high. Therefore an efficient way of the data evaluation is needed. In this paper we report the development of Hubert software package as a response to the rapidly developing field of in-situ NFS experiments. Hubert offers several useful features for data files processing and could significantly shorten the evaluation time by using a simple connection between the neighboring time spectra through their input and output parameter values. [ABSTRACT FROM AUTHOR]

57Fe75Mo8Cu1B16 metallic glass prepared by single roller melt spinning was investigated by conversion electron Mössbauer spectroscopy, conversion X-ray Mössbauer spectroscopy and high-energy X-ray diffraction. All methods confirmed presence of amorphous structure without traces of a crystalline phase. Results obtained by Mössbauer spectrometry suggest predominant appearance of magnetic regions on side of the ribbon which was in contact with the quenching wheel. In situ High-energy X-ray diffraction experiment revealed transition from ferromagnetic to paramagnetic state and it was even possible to estimate the Curie temperature [ABSTRACT FROM AUTHOR]