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The infusion from the aerial part of common lady’s mantle Alchemilla vulgaris L. injected preliminarily for 5 d exhibited neuroprotective properties by normalizing conditioned reflexes and orientational-exploratory behavior indicators of animals after hypoxic exposure. Infusion at a dose of 5 mL/kg was the most active. A. vulgaris infusion at a dose of 5 mL/kg with activation of lipid peroxidation after hypoxic action normalized the content of thiobarbiturate-reactive products in brain homogenate and reduced the concentration of antiradical antioxidants in the lipid extract.

In this work an arc model is employed along with electric and spectroscopic measurements to study DC electric arcs in Ar and CO2. The model is aimed at describing the arc and the electrodes. Simulation and experimental results are shown for currents between 150 A and 210 A.

The paper is concerned with the state-of-the-art nonequilibrium modelling of a DC tungsten-inert gas arc plasma. The advanced description involves the two-way interaction between the plasma and the electrodes. Results in atmospheric pressure argon demonstrating important features of the arc plasma are presented and discussed. First results in the presence of metal vapour released from the molten anode are presented. Outlook for further developments in nonequilibrium arc modelling are discussed.

An appropriate coupling of an arc plasma column in the state of local thermodynamic equilibrium to a refractory cathode necessarily involves the non-equilibrium boundary layer between them. A model has been developed that combines a model of an equilibrium direct current arc plasma in atmospheric pressure argon with the assembly of a cathode made of tungsten and the boundary layer. A bidirectional coupling has been realized that allows us to consider a variable voltage drop across the boundary layer for different positions on the cathode. The results are obtained for arc currents between 10 and 150 A in the cases of both a unidirectional and a bidirectional coupling. The results show differences in the distributions of the temperature and the normal current density on the cathode surface and the radial and axial distributions of the plasma temperature. Comparison with the results of a fully non-equilibrium model of the arc plasma and experimental findings from optical emission spectroscopy shows a fair agreement for currents, where the deviations from equilibrium in the arc column can be ignored. For arc currents beyond 100 A, the arc attachment on the cathode appears in two forms, which differ from each other in the distributions of the temperature and the normal current density on the cathode surface, whereas the values of the total arc voltage are close to each other.

The design of alloys, that economize strategic element as chromium requires detailed physical investigations of their structure and phase composition. In the search for new materials in the last two decades a new class of Fe alloys was composed—the so‐called nitrogen steels. The contemporary achievements in the casting technology—the use of nitrogen under high preasure above the melt—made possible the production of Fe alloys with nitrogen concentration even above 0.4 wt%. The wide application of investigated alloy system is connected with creation of alloys without presence of strong carbides‐forming elements. The microstructure and phase formation of these new materials are insufficiently studied. The aim of this work is to characterize the microstructure and phase composition of two series Fe‐alloys casted with and without nitrogen pressure above the melt. The so cast steels appear as experimental ones and they are directed to demonstrate the possibility for nitrogen doping of steels without presence of...

Renal stones were investigated by X‐ray diffraction. The obtained results showed only one crystal phase in every sample. With the aim to verify eventual availability of second phase (under 3 volume %) the same renal stones were investigated by neutron diffraction. The neutron spectra proved that additional crystal phase was absent in the renal stones. The obtained results are scientific‐practical, in aid of the medicine, especially in the case of renal stone disease.

By neutron diffraction the evolution of phase composition of Fe‐20Cr‐(8 to 24)Mn‐0.6N steels was investigated versus the Mn concentration.

Publisher Summary This chapter highlights clinoptilolite (Cpt) and the possibilities for its application in medicine. Cpt is widespread in the northeastern (NE) part of the Rhodopes mountains in Bulgaria. In respect to the possibilities of the use of Bulgarian clinoptilolite in medicine, its toxic, genotoxic and carcinogenic effects on laboratory animals, are studied in the chapter. In the same relation, the natural radioactivity of Cpt, of the animal's food, containing Cpt and of the animals faeces, is measured. The contents of radium ( 226 Ra) in drinking water, percolating through Cpt rocks and the concentration of radon ( 222 Rn) in Cpt-built houses are also evaluated in the chapter.