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[en] Influence of low-intensity ionizing radiation with single dose (0.055 Gy x min-1) in doses of 0.1, 0.5, and 1.0 Gy on a metabolic state of the respiratory chain of rat's small intestine mitochondria is investigated. The damage of relations of the oxidative phosphorylation processes in mitochondria, which is expressed in the uncoupling of the processes of respiration and phosphorylation and in a decline of the phosphorylation rate and the activity of ATP-hydrolase reactions, is established. These changes are observed at all time of research and intensified with a growth of the radiation absorbed dose.
[en] With the aid of the polarization curve method using a microcapillar, optical microscopy of the sample surface before and after the anodic polarization, and EDX, the peculiarities of electrochemical corrosion of aluminum alloys of the Al-Zn-Mg-Cu system in a 0.1 M NaCl solution are studied. It is established that the process mechanism corresponds at first to solving the Mg2Si phase in the electrolyte and then to the corrosion attack of the matrix with the pitting. It has been shown that, at the selective dissolution of magnesium from the Mg2Si phase, a definite amount of SiO2 oxide has been formed.
[en] It is shown that the low-energy ultrasonic treatment of steel 20 in a constant magnetic field doesn't lead to a substantial change in the structure composition. It is established that the dislocation density in steel 20 decreases after the ultrasonic treatment in a constant magnetic field by about 40%. The calculated mass-transfer coefficient of 63Ni into steel 20 is DM=7.4 x 10-11 cm2/s.
[en] Among three stable magnesium isotopes, 24Mg, 25Mg, and 26Mg with natural abundance 79, 10, and 11%, only 25Mg has the nuclear spin (I=5/2) and, therefore, the nuclear magnetic moment. Two other isotopes are spinless (I=0) and, hence, have no magnetic moment. We have revealed that magnetic isotope 25Mg, by comparison to nonmagnetic isotope 24Mg, essentially stimulates the recovery process in the yeast cells, Saccharomyces cerevisiae, after UV irradiation. Thus, we have first documented the magnetic isotope effect in radiation biology. This finding opens up the way to the development of novel radio-protectors based on the stable magnetic isotopes.
[en] A systematic study of the alloys of Zr50Co50-xNix (0< x<50) composition with the help of X-ray diffractometry, differential thermal analysis, and optical metallography is carried out. It is shown that the formation of a low-symmetry B33 structure in Ni-rich intermetallics occurs by diffusion at temperatures higher than 0.8 Tmelt. The phase formation changes into the diffusionless martensitic transformation in intermetallics with Ni content below 30 at. %, as the temperature decreases. In the latter case, the B2 austenitic phase is formed by diffusion and transforms on cooling below 0.8 Tmelt into two martensitic phases ordered by B33 and B19' structure types.
[en] The fabrication technology of articles formed by the active brazing of size-limited separate boron nitride elements is developed. Solid articles of construction appointment are obtained: shafts (axles) to 10 mm in diameter of a necessary length; practically wear-free bearings without lubricant of the shaft/bush type; saddles; baseplates; machine tools rails, etc., with the cubic boron nitride on cubic boron nitride friction surface.
[en] The dose dependences of the aberrant anaphases in the root meristem in 48 hours after the irradiation have non-linear character and a plateau in the region about 6-8 Gy. The plateau indicates the activation of recovery processes. In the plateau range, the level of damages for this genotype is 33% for aberrant anaphases (FAA), 2.3 aberrations per aberrant anaphase (A/AC), and 0.74 aberrations for the total number of anaphases. At 10 Gy, the dose curve forms the exponential region caused by the involvement of the large number of new cells with unrepaired damages in the mutation process. The increase of A/AC to 1.1 indicate the ''criticality'' of the meristem radiation damage.
[en] The dynamic behavior of dislocations under the influence of X-ray radiation and the combined (X-ray + magnetic field) influence on silicon crystals is investigated. The changes in microplastic characteristics of silicon crystals are analyzed under the assumption of interdefect transformations.
[en] Z-ray emission (XE) OK α, TiLα, and ZrLβ2, as well as X-ray photoelectron (XP) valence-band and core-level spectra, have been derived for ZrTiO4 and HfTiO4 oxides. Both the theoretical data and X-ray results show the similarity of the electronic structure of both titanates and indicate that their valence bands are dominated by the contributions of O2p states. These states contribute predominantly in the upper portion of the valence band
[en] The optimal control problem for the transport of a radioisotope mixture is investigated. The theorem on existence and uniqueness of an optimal control is proved, and the algorithm for solving the optimal control problem is developed.