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Softening effect of grain-boundary sliding (GBS) in h.c.p. α-Mg polycrystals arises in the stress–temperature ranges of interest for automotive applications. Furthermore, decomposition of the oversaturated α-Mg solid solution is accompanied by apparition of a microstructure, which is unstable during a creep. These two main effects deteriorate most likely the microyield resistance and long-term strength of magnesium alloys of Mg–Al–Mn and Mg– Al–Zn systems. According to the data of internal-friction measurements, the introduction of Ca suppresses GBS that gives rise to the GB strengthening of the ternary Mg–Al–Ca system. An introduction of small additions of Ti (about 0.1–0.2%) causes significant solid-solution strengthening due to solute-atmosphere retardation of moving dislocations by the Cottrell mechanism with binding energy of about 0.27 eV. The idea of dynamical self-strengthening of α-Mg matrix during the creep is also supported by precise x-ray diffractometry. As deduced, observed high microyield resistance and excellent long-term strength of the magnesium alloys of Mg–Al–Ca system containing inexpensive additions of Ti are due to minimizing recovery and softening effects at elevated temperatures at the expense of thermal phase-composition and concentration stabilization of α-Mg solid solution. Thermally-activated dislocation relaxation accommodated by the diffusion of alloying elements (Al, Ca, Ti in their best combination) should be considered as dominant (rate-controlled) microyield mechanism, which provides creep strain rate of 10^−9–10^−10 1/s. Its activation increases essentially (by 150–200°C) the heat resistivity of new experimental alloys.

The first experimental evidences are obtained by the mechanical spectroscopy, which yield forming the pair defects, i.e. primary nanoclusters of alloying element (AE) — excess vacancy (EV) at the early (pre-precipitate) stage in segregated solid solutions of as-cast eutectic alloys of Mg–Ba system. At the later stages, the clustering rate is increased by the presence of EV and completed by the stress rearrangement of AE–EV nanoclusters into magnesium clusters Mgn alloyed by the emission-active Bam additions. It is noteworthy that thin structure of electron spectra is theoretically calculated for (Mg16Ba2) clusters using the first principles by the linearized augmented plane-wave (FLAPW) method with a complete approach for crystal-potential approximation of electronic structure of the x-ray photoelectron spectra (XPS) observed for massive (bulk) Mg–2% Ba (Mg0,94Ba0,06) alloy. Change of thin structure of XPS, occurrence of chemical shifts in Auger electron spectra (AES), and amplification of paramagnetic susceptibility of Mg–Ba alloys show that, as alloying element, Ba eliminates the minimum on a curve of electron density of states, N(E), which is typical for the IIA subgroup semibrittle light metals, and raises the local density of engaged states near the Fermi surface (EF). As revealed, embedded MgnBam clusters are responsible for hybridization of chemical bounds in segregated solid solutions with stabilizing the new hybrid s-, p-, d-electron configurations of clusters properly keeping their property to operate as emission-active centres raising a stable quantum yield of the photoemission. High quantum efficiency of the Mg–Ba alloys in a near UV-range of spectrum is explained by the surface-bulk character of the photoemission effect for eutectic alloys with clusterized structure having effective (at structural defects) mutual solubility of components (Mg and Ba).

The character and sequence of changes in the tissues structure of the gastrointestinal walls under the impact of the impulse and constant delivery of electric pressure with frequency 440 kHz were studied. The investigation object was squeezed, using the force, measured from 2 to 6 N/mm2. The ЕКВЗ-300 «Patonmed» apparatus was used as a source of supply. Еlectric parameters of the process was fixed, using the analogue-numerical digital converter LCard E20-10 and laboratory oscilloscope Tektronix TDS 3014C. There was established, that electric conjunction of stomach and small intestine include three elements: destroying and disappearance of mucosa, connective tissue and membranes; fusion of the collagen fascicles and the smooth muscle cells; the loss of the collagen fascicles and the smooth muscle structure and creation of homogenous еlectric welding suture. The first two elements of the electric welding anastomosis are occurring simultaneously, but not dependent one from the other. At the welding suture completion the nondestructive changes of the tissues are spreading on a distance not more than 1 mm beyond the borders of the electrods apposition.