The hydrogenation of a crystalline Ni-Fe (80 wt.% Ni, 20 wt.% Fe) powder mixture leads to the formation of a mixture of Face Centered Cubic (FCC)-Ni and FCC-Fe phase nanocrystals embedded in an amorphous matrix. The magnetic susceptibility of the nanostructured powder is 2.1 times higher than that of the as-produced crystalline mixture. Heating in the temperature range 420-590 K causes structural relaxation in the hydrogenated powder, resulting in an increase of the magnetic susceptibility and a decrease of the electrical resistivity. During the heating procedure, the reorientation of magnetic domains in nickel and iron takes place in the temperature range 580-650 K and 790-850 K, respectively. In the pressed sample from the powder mixture, the crystallization of the amorphous phase of nickel and its FCC lattice crystalline grain growth occurs in the temperature range 620-873 K causing a decrease in the magnetic susceptibility of the nickel FCC phase and a sudden drop in the electrical resistivity. Prolonged heating of the mixed powders at 873K results in the formation of a Ni-Fe solid solution with higher magnetic susceptibility than the starting mixture.

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In this study it was investigated influence of temperature and frequency on permeability, coercivity and power loses of Fe81B13Si4C2 amorphous alloy. Magnetic permeability measurements performed in nonisothermal and isothermal conditions was confirmed that efficient structural relaxation was occurred at temperature of 663 K. This process was performed in two steps, the first one is kinetic and the second one is diffuse. Activation energies of these processes are: Ea1 = 52.02 kJ/mol for kinetic and Ea2 = 106.9 kJ/mol for diffuse. It was shown that after annealing at 663 K coercivity decrease about 30% and therefore substantial reduction in power loses was attained. Investigated amorphous alloy satisfied the criteria for signal processing devices that work in mean frequency domain

European honeybee colonies are the most important pollinator insects and source of honey and other useful products. Honeybee colonies today face new diseases and pests as well as pollution which threaten their survival and endanger whole food production which relies on honey bee pollination. Internet of Things (IoT) technology enables integration of wireless sensors inside beehives to enable remote monitoring of various beehive parameters from remote location using Internet. Detection of certain critical events in beehive is hard to be explicitly program due to complex dependence between multiple input parameters. Machine learning algorithms give computers the ability to learn to detect these events without being explicitly programmed. Detection of these event from streams of data collected from IoT sensors is possible using Complex Event Processing (CEP) which applies machine induced knowledge do detect and warn beekeepers about certain events in beehive.

The method of differential scanning calorimetry (DSC) was employed to examine the crystallization process of amorphous powder of the Ni80Co20 alloy in the temperature interval from room temperature to 1000K. It is shown that the crystallization process of this alloy's powder proceeds in two stages at temperatures T1=690K and T2=790K. The relative changes in the electron density of states in the vicinity of Fermi level were determined from the changes in the slope of the thermo-electromotive force (TEMF) temperature coefficient before and after each stage of crystallization process. The obtained results show that the relative change in the electron density of states is 34.9% after the first crystallization stage and 38.9% after the second one. The changes in the specific electrical resistance of the pressed powder as a function of temperature are fully correlated with the change in the electron density of states and results of the DSC method. The observed rapid decrease in the specific electrical resistance after each crystallization stage is caused by the increase of the mean free electron path and increase in the electron density of states