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Electrical transport in mixed ion-polaron glasses has been investigated in four series of glasses containing transition metal oxides (TMO) namely WO3/MoO3, and Na+/Ag+ ions with the composition xWO3-(30-0.5x)Na2O-(30-0.5x)ZnO-40P2O5, xWO3-(30-0.5x)Ag2O-(30-0.5x)ZnO-40P2O5, xMoO3-(30-0.5x)Na2O-(30-0.5x)ZnO-40P2O5, and xMoO3-(30-0.5x)Ag2O-(30-0.5x)ZnO-40P2O5, 0 ≤ x ≤ 60 (mol%). The DC conductivity of Na-glasses up to 30 mol% of WO3 and MoO3 is almost identical due to the dominance of ionic conductivity. In this compositional region, the introduction of tungstate and molybdate units increases the mobility of sodium ions and compensates the decrease in sodium number density. On the other hand, with increasing WO3 and MoO3 content and decreasing Ag+ ion concentration in Ag-glasses the DC conductivity decreases for few orders of magnitude. A significant difference in conductivity is observed for glasses with higher WO3 and MoO3 content. While for glasses containing WO3 the conductivity rapidly increases due to a huge polaronic contribution indicating a turnover from predominantly ionic to polaronic transport, the conductivity for MoO3-glasses decreases in the entire mixed compositional range suggesting dominant ionic transport. The changes in the conduction mechanism with the systematic alternation of the glass composition have been analyzed in correlation with the structural modifications and variations of molybdenum and tungsten in different oxidation states. This work is licensed under a Creative Commons Attribution 4.0 International License.

Electrical transport in mixed ion-polaron glasses has been investigated in four series of glasses containing transition metal oxides (TMO) namely WO3/MoO3, and Na+/Ag+ ions with the composition xWO3-(30-0.5x)Na2O-(30-0.5x)ZnO-40P2O5, xWO3-(30-0.5x)Ag2O-(30-0.5x)ZnO-40P2O5, xMoO3-(30-0.5x)Na2O-(30-0.5x)ZnO-40P2O5, and xMoO3-(30-0.5x)Ag2O-(30-0.5x)ZnO-40P2O5, 0 ≤ x ≤ 60 (mol%). The DC conductivity of Na-glasses up to 30 mol% of WO3 and MoO3 is almost identical due to the dominance of ionic conductivity. In this compositional region, the introduction of tungstate and molybdate units increases the mobility of sodium ions and compensates the decrease in sodium number density. On the other hand, with increasing WO3 and MoO3 content and decreasing Ag+ ion concentration in Ag-glasses the DC conductivity decreases for few orders of magnitude. A significant difference in conductivity is observed for glasses with higher WO3 and MoO3 content. While for glasses containing WO3 the conductivity rapidly increases due to a huge polaronic contribution indicating a turnover from predominantly ionic to polaronic transport, the conductivity for MoO3-glasses decreases in the entire mixed compositional range suggesting dominant ionic transport. The changes in the conduction mechanism with the systematic alternation of the glass composition have been analyzed in correlation with the structural modifications and variations of molybdenum and tungsten in different oxidation states. This work is licensed under a Creative Commons Attribution 4.0 International License.

Nanoparticles of iron boride (Fe2B, Fe2B coated in SiO2, FexCo2−xB coated in SiO2) were synthesized using the reduction of metal ions by sodium borohydride. X-ray diffraction confirms the amorphicity of the coated compounds and scanning electron microscope imaging revealed the nanoparticulated structure of all compounds. The splitting between zero-field-cooled and field-cooled temperature dependent magnetization curves point to the blocking of superparamagnetic particles magnetization. Magnetic hysteresis loops are however consistent with the combined effects of blocked superparamagnetic and ferromagnetic (multidomain) particles. The observed quite complex magnetic behaviour is in accordance with structural studies, where additional phases and broad distribution of particle sizes were identified.

During the performance of a musical composition a special human environment comes into being. We aim to interpret the compositions as a specific class of human environment in order to utilise that for description of structure and dynamics of general human environment. In particular, we analysed four Bach's fugas considering their motifs and introducing the concept of the energy of a motif. We used bosonic excitations from theoretical physics as an analogical starting point for this concept, with the aim of proposing a new way to shed light onto more complex human environments. The aim is neither to reduce music to physical theories nor to define new theories of music, but to approach the investigation of complex environments in a new way, using already existing concepts.