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Abstract
The Mössbauer parameters of tin in aluminium matrix were studied and published in an earlier paper1. The aim of this work was to carry out investigations on tin in an aluminium alloy containing magnesium, silicon and lead beside the Mössbauer active tin. The effect of heat treatments on the formation of intermetallic compounds was studied by X-ray diffraction and by the Mössbauer spectra of119Sn.
Abstract
Mössbauer spectroscopy, X-ray diffractometry and differential scanning calorimetry were used to study the effect of the preparation parameters on the short range ordering of Fe83P17 amorphous alloys. The samples were quenched with different quenching rates from the melt which was kept either at 1100°C or 1250°C for 20 min. The short range order of the amorphous samples was found to depend on the quenching rate due to the relaxation taking place during rapid quenching of the melt. In one case, in the sample quenched with the lowest quenching rate from the melt of 1250°C, crystalline phases identified as Fe3P and 
-Fe were also found. This phase separation can be understood by taking into consideration the effect of both the melt temperature and the quenching rate. In this case, the cooling time can be long enough for separation of the phases which can be expected within the range of 1040–1250°C according to the phase diagram.
Abstract
BaTiO3, was studied by positron lifetime spectroscopy in static electric fioeld. The strength of the field was varied from 0 up to 104 V/cm. Two characteristic points were found at 4500 V/cm and at 8500 V/cm. These field strengths were related to subsequent ordering processes of the crystal. Additional temperaturee dependent measurements were perforrmed in the 70–310 range to confirn the interopretaion of the two positron lifetimes. The two expected phase transitions were observed and these measurements showd that positron are trapped by Ba vacancies.
Abstract
Conversion electron Mössbauer spectroscopy (CEMS) and XPS has been used for the surface analysis of an 
X10CrNiTi 18/9 (DIN 1.7440)
-type stainless steel in order to determine the supposed structural and/or chemical changes in the surface layer caused by polishing. Both, CEMS and XPS results can be associated with the appearance of Fe nitride in the outer layer of steel samples after polishing, while no sign of nitrogen was detected in the bulk material.
Abstract
A stacking Mössbauer technique, MMS has been applied for studying thin surface layers. The surface layers formed on the57Fe film in aqueous solutions of corrosion inhibitors, such as zinc phosphate and barium metaborate, and in distilled water was studied by this method. It has been found that the corrosion is much slower in the presence of zinc phosphate and barium metaborate. XPS analysis suggests the formation of a mixed iron zinc phosphate on the surface of the57Fe film after corrosion in a zinc phosphate solution.
Abstract
A special Mössbauer technique, MMS has been used for the study of corrosion on the surface of57Fe layers, under two types of organic coatings. The corrosion processes were followed by the Mössbauer spectra.
Abstract
119Sn conversion electron Mössbauer spectroscopy, X-ray diffractometry and energy dispersive X-ray analysis (EDAX) were employed to investigate microstructure, composition and phases present in as-electroplated Sn-Cr and Sn-Cr-Zn alloys deposited on copper substrates. In the Sn-Cr deposits Cu, 
-Sn, Cr-Sn phases can be identified by X-ray diffractometry. The phase composition is significantly different between the samples prepared with relatively higher and lower current densities. In the diffractograms of Sn-Cr-Zn deposits Cu, -Sn, Zn phases can be well identified. A small intensity amorphous peak is also present, which can perhaps be associated with the presence of some amorphous Zn and Sn alloy. 119Sn Mössbauer spectra of Sn-Cr deposits exhibit an asymmetric broad main line centered near the isomer shift characteristic of -Sn as well as they contain a small component near the zero velocity which can be attributed to a SnO2 phase based upon its characteristic. 119Sn Mössbauer spectra of Sn-Cr-Zn deposits are roughly similar to those of Sn-Cr deposits although the Mössbauer parameters of the third phase are different and vary with the Zn content. The presence of SnO2 on the surface mainly in the Sn-Cr samples can be attributed to the corrosion process in the air.
Abstract
151Eu Mössbauer spectrum of IR-transmitting calcium aluminate glass, 60CaO·32Al2O3·5Fe2O3·3Eu2O3, consists of a broad peak due to distorted Eu(III) with 
and 
values of 0.91 and –2.02 mm·s–1, respectively. Debye temperatures (
D) of 360 and 320 K were obtained from the temperature dependence of absorption area (A) and that of , respectively. These
D values indicate that Eu(III) atoms occupy substitutional sites of distorted Al(III)O4 tetrahedra in calcium aluminate glass. The value of 0.62 mm/s obtained from the heat-treated sample (glass ceramic) indicates that Eu(III)-O bonds became less covalent. A smaller value of –1.20 mm·s–1 was obtained for Eu(III) in the glass ceramic, indicating less distorted Eu(III)O4 tetrahedra.
Abstract
Nuclear inelastic resonant scattering of synchrotron radiation was applied to the study solutions of 57Fe complexes. In order to reveal different inelastic contributions solutions of two different 57Fe complexes of different molecular dimensions with solvents of substantially different viscosities were studied. We argue that the only former experiment available in the literature overestimates the role of the diffusivity in affecting the spectrum. The first direct observation of an intramolecular vibrational transition assisting the nuclear resonance absorption in a liquid is reported.
Abstract
The total area of the57Fe Mössbauer spectra of the EuBa2 (Cu0.98
119Sn0.01
57Fe0.01)3O7-
superconductor exhibited a highly usual anomalous temperature dependence, i.e. it increased monotonously with increasing temperature between 120 and 300 K. We found also anomalous changes in the57Fe Mössbauer parameters around Tc. These latter changes could be associated with phonon softening and low temperature phase transformation.
