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Mossbauer spectrometry (57Fe transmission and conversion-electron techniques), differential scanning calorimetry, and x-ray diffraction are employed to study the microstructure and magnetism of amorphous and nanocrystalline Fe80Mo7X1B12 (X = Cu, Au) alloys. Heat treatment of amorphous specimens below the temperature of primary crystallization causes structural relaxation that, in turn, stabilizes the amorphous arrangement. Changes observed in the topological short-range order are more pronounced for X = Au because this alloy shows a higher degree of disorder in the bulk of the as-quenched state. For both alloys, three-step crystallization behaviour is observed. Annealing performed in temperature range of the first crystallization provided different amounts of body-centred-cubic Fe nanograins. Magnetic interactions among them and their impact on the surrounding amorphous residual matrix are discussed using hyperfine-field distributions. Differences in hyperfine interactions between surface regions and bulk of the alloys are revealed from conversion-electron Mossbauer spectrometry and transmission Mossbauer effect measurements, respectively. The magnetic behaviours for X = Cu and Au are very similar after annealing at temperatures close to and beyond the end of the first crystallization peak. The impact of which element is present on the microstructure and magnetism is crucial during the commencement of the crystallization but it cannot be discerned for higher crystalline contents.

Calculated triple differential cross sections for the ionization of water by positron and electron impact are compared. Results are showed for coplanar and non-coplanar geometrical arrangements.

Triple differential cross sections for the ionization of water by electron impact are reported. The calculations were performed both for coplanar and non-coplanar geometries.

Ionization of the CH4 molecule in collision with energetic protons has been investigated by applying the continuum distorted wave with eikonal initial state approximation extended for multi-centre collisions. Total and double differential net and q-fold ionization cross sections have been evaluated which show good agreement with experimental data. Electron distribution characteristics to the structure of the molecule have been revealed in the impact parameter dependence of ionization probabilities. Dissociation of the molecule has also been considered. Present results for the production of CH ions (n = 1–4) are in good agreement with the available experimental data.

TDCSs for the ionization of N2 by electron impact were calculated. The kinematical conditions of the ionization process imply intermediate impact energies and large ion recoil momentum.

We have calculated triple differential cross sections (TDCS) for the ionization of the nitrogen molecule by electron impact. The measured recoil-to-binary peak ratio for the outer valence orbitals (3σg, 1πu, 2σu) of the target is well reproduced by our models. One of our models is better for the description of the binary region of the TDCS, while the other reproduces a better recoil peak, similar to our previous observation for the CH4 molecule.

Triple-differential cross sections for the ionization by electron impact of the inner (2a1) and outer (1t2) valence orbitals of the CH4 molecule were calculated in the framework of the distorted-wave Born approximation. We have shown that our description of the interaction between the outgoing electrons and the residual ion reproduces well the experimental data for both the binary and recoil peak regions.

Steam generators of four VVER–440 units at nuclear power plants V-1 and V-2 in Jaslovske Bohunice (Slovakia) were gradually changed by new original Bohunice design in period 1994-1998. Corrosion processes before and after these design and material changes in Bohunice secondary circuit were studied using Mossbauer spectroscopy during last 25 years. Innovations in the feed water pipeline design as well as material composition improvements were evaluated positively. Mossbauer spectroscopy studies of phase composition of corrosion products were performed on real specimens scrapped from water pipelines or in form of filter deposits. The corrosion of new feed water pipelines system (from austenitic steel) in combination to innovated operation regimes goes dominantly to magnetite. The hematite presence is mostly on the internal surface of steam generator body and its concentration increases towards the top of the body. In the results interpretation it is necessary to consider also erosion as well as scope and type of maintenance activities. The long-term study of phase composition of corrosion products at VVER reactors is one of precondition for the safe operation over the projected NPP lifetime.

Potassium white micas from the rocks included into Cretaceous deformation zones (ca. 100–70 Ma in age) of the Central Western Carpathians were investigated by Mossbauer spectroscopy. White micas formed during a polystage evolution and changing P-T conditions of their crystallization in crustal-scale shear zones. We found criteria for distinguishing generations of celadonite-poor (muscovitic) and celadonite-rich (phengitic) white micas using Mossbauer spectroscopy. This method revealed contrasting spectra characterized by typical quadrupole doublets corresponding to Fe2+ Fe3+ contents in white micas. They are in the range of 2.9–3.0 mm/s for phengite, and 2.6–2.7 mm/s for muscovite. Mossbauer spectra reflect well the chemical changes in white mica aggregates, especially of those close to the end-member muscovite and (alumino-)celadonite compositions.

Theoretical cross-sections for the ionization of the water molecule by electron and positron impact are presented. The calculations were performed in the framework of the simpler CPE and two distorted-wave models, ES and TS, by employing Gaussian wavefunctions for the description of the target. We found good agreement with the experiment, especially for higher impact energies.