[en] A device for isotope capsule transport and unloading at nuclear reactors is described. The device comprises a drive, truck with a cylindrical container supported as a cantilever and a guiding rail. To simplify the device, the bottom of the container is made mobile and a stop corresponding to the unloading position of the truck is fixed on the rail to displace container bottom. The pipeline for transporting capsules onto the delivery table is installed under the truck coaxially with the container. The device operates in the following way: the mechanism for capsule loading into the container in the lower position of the truck places a capsule into the cylindrical container, the inlet ope--ning of the container being shut off by the mobile bottom. Then the rope moves the truck up in the direction of the rail. In the upper position the container bottom comes on the stop, the bottom is displaced, the opening is clear and the capsule falls into the pipeline under its own weight and is transported along the pipeline to the delivery table

[en] The LMTO/Green's function method has been used in calculating the electronic structure of cubic carbides, nitrides, and oxides of titanium and vanadium containing metallic and metalloid vacancies. Changes in the energy spectra of the compounds are examined in relation to the concentration of lattice defects. The data are compared with results available from calculations of nonstoichiometric phases using cluster and band models, and also with data obtained by x-ray emission spectroscopy

[en] Pilot investigations are considered of aqueous-extraction regeneration of fast reactor spent fuel in hot chambers. Results of observations of features of regeneration processes at different extractors are described. Extractor choice is substantiated and design concepts for developing industrial extraction regeneration of the mixed uranium-plutonium fuel are presented

[en] The authors perform band-structure calculations using the Green's function method in the atomic spheres approximation for titanium carbide containing isolated substitutional impurities such as nitrogen and oxygen atoms. The basic equations for the calculation are given. Histograms are presented of the total and partial densities of states N(E) of ideal TiC obtained by applying the Green's function-ASA-KKR method. Results of the calculations of the local electronic states of nitrogen and oxygen impurity atoms together with the density of states of carbon in the carbide are given. The results of the calculations are compared with the available x-ray-emission spectra of titanium oxycarbides and carbonitrides

[en] Band calculations of an electron energy spectrum of cubic molybdenum carbide, as well as MoC, containing isolated carbon vacancy and metal impurities of substitution (Sc, Ti, V, Cr, Mn, Y, Zr, Nb, Tc) are carried out. Dependence between specific features of electron states of defects mentioned and their stabilizing action on the cubic structure of high-temperature α-MoC phase is discussed. Comparison of the results obtained with the data on stability of cubic molybdenum carbide alloyed with d-metal additions is carried out

[en] We have carried out the first-principle calculation of the electronic structure of ruby (Cr impurity in Al₂O₃). Our results showed that the crystal lattice distortion lifted degeneracy of 3d levels of Cr ions. When the Coulomb interaction between 3d-electrons of Cr ions was taken into account via the LDA+U calculation scheme, the energy gap increased. The obtained value of the first excitation from the valence band to the first empty impurity state agreed well with the optical spectroscopic data

[en] Self-consistent band calculations of ZrB, ZrC, ZrN, PdH (structure of NaCl type) and CaH₂, ScH₂, TiH₂, VH₂ (structure of CaF₂ type) both complete and those, containing metalloid and metal insulated structural vacancies, are conducted by method of Green LMTO-functions. The nature of vacancy states in introduction phases, as well as crystal defects effect on electron and energy characteristics of the given compounds are being discussed

[en] The electronic structure of impurity atoms of 3d-transition metals substituting the Cu node in the copper-oxygen chain of YBa₂Cu₃O₇ compound is determined. It is shown for Cr, V, Ti and Sc impurity atoms that the closer is the impurity atom to the beginning of the 3d-series, the higher is the energy of the d-band centre and the weaker is hybridization of d-states of the impurity with p-states of oxygen atoms of the chain. In case Co, Fe, Mn magnetic impurities strong hybridization of d-states of the impurity and p-states of surrounding oxygen atoms is observed. Co, Fe, Mn impurity atoms have local magnetic momenta and the Fe atom momentum is greater than those of Co and Mn atoms

[en] The optical properties of the CeFeSi-type GdTiGe and GdTiSi compounds have been investigated in the spectral range λ = 0.22-16 μm. The optical constants and parameters of charge carriers (plasma and relaxation frequencies) were determined for both alloys. A self-consistent calculation of the electronic structure of these compounds was performed using the LDA + U method. Total and partial densities of states have been calculated. A strong hybridization between the d-states of Gd and Ti was found and a significant width of the f-band was observed in calculations. The calculations indicate also that significant polarization of the Ti 3d electrons was occurred which may be related to the indirect exchange interaction with magnetic moments of Gd atoms. These data were used to interpret the dispersion of the optical conductivity of the compounds. Essential agreement with experiment was observed, especially for GdTiSi

[en] Results of anion exchange refining of plutonium and neptunium during reprocessing of exhausted fuel elements of power water-moderated reactor by metal sorption from 7.5 M HNO₃ on the high-basicity vinyl-pyridine anionite AB-23M, have been presented. The effect of preparation of the valent species Pu and Np and the method of their separation for fission product purification has been shown