No abstract available

[en] Experience is presented on the merging of the probabilistic safety analysis (PSA) model (which was created using the ADAPT code) and the integrated code for modeling beyond-design MAAP4 crashes. As an example, a group of initiating events of the PSA model 2, leading to complete loss of external and internal power supply sources of the station, was analyzed. Estimates of the probabilities of various loss scenes of the hermetically sealed container (containment) due to severe accidents of the pressure vessel body (induced vaporization of the steam generator tubes, combustion of hydrogen, detonation of hydrogen, loss of the containment after spraying the fuel upon rupture of the reactor vessel and others) based on 10,000 MAAP4 calculations. The obtained results allow to conclude that the analyzed model of the second-level PSA gives a fairly conservative estimate of the probability of loss of the containment due to the serious accident. At the same time, calculations made using dynamic event trees indicate higher probability of dependent failures of certain designs, systems and elements of the reactor installation. The results obtained make it possible to significantly reduce the uncertainty of the PSA model, which is very important for making optimal decisions

[en] We explore gauge fields-strings duality by means of the loop equations and the zigzag symmetry. The results are striking and incomplete. Striking -- because we find that the string ansatz proposed in satisfies gauge theory Schwinger-Dyson equations precisely at the critical dimension D_cr=4. Incomplete -- since we get these results only in the WKB approximation and only for a special class of contours. The ways to go beyond these limitations and in particular the OPE for operators defined on the loop are also discussed

[en] A Sodium Fast Reactor is a good candidate for an application of dynamic probabilist risk assessment due to long mission times and possible system recoveries. In this paper, we present a new approach to construct the dynamic probabilistic model of the Decay Heat Removal (DHR) function of a Sodium Fast Reactor. We use Distributed Stochastic Hybrid Automata concept with the PyCATSHOO modeling tool. The proposed approach allows to construct a dynamic probabilistic model of a SFR DHR function that incorporates the time evolution of physical parameters and dynamic changes in the states of DHR systems (failure or recovery of DHR system components) and presents enough flexibility to be applied at the design stage. (author)

[en] Sodium Fast Reactor is a good candidate for an application of dynamic probabilist risk assessment due to long mission times and possible system recoveries. In this paper, we present a new approach to construct the dynamic probabilistic model of the Decay Heat Removal (DHR) function of a Sodium Fast Reactor. We use Distributed Stochastic Hybrid Automata concept with the PyCATSHOO modeling tool. The proposed approach allows to construct a dynamic probabilistic model of a SFR DHR function that incorporates the time evolution of physical parameters and dynamic changes in the states of DHR systems (failure or recovery of DHR system components) and presents enough flexibility to be applied at the design stage. (author)

[en] The X-ray luminescence and photoluminescence of the ultradispersed Gd₂O₃ powders with different purity were investigated in 90-360 K temperature range. Both impurity and intrinsic optical active centers were detected. The effect of energy transfer from Gd³+ to RE³⁺ ions was observed. (paper)

[en] The features of electron transitions in the region of fundamental absorption edge as well as vibrational characteristics are investigated in Gd₂O₃ nanoparticles doped with Er³⁺ ions at 0.25-8 mol% concentration. The analysis of initial reflection data is performed for cases of direct and indirect interband transitions. The dependences of corresponding energy gaps on activator concentration are obtained. The effect of strong decrease in the phonon frequency under doping of matrix with a small amount of Er³⁺ is found. The obtained data open new opportunities for improving the efficiency of energy conversion devices. (paper)

No abstract available

[en] The basic requirements for the crystal lattice and defectiveness of Gd₂O₃ matrix as well as for the concentration of Er³⁺ dopants to achieve the enhanced parameters of energy conversion in Gd₂O₃:Er nanoparticles are summarized. The obtained data allow to optimize and improve the functional characteristics of Gd₂O₃:Er-based down-conversion layers applying in solar cells. (paper)

[en] The optical properties of Gd₂O₃:Er (0.25-8 mol%) nanoparticles have been investigated. The observed effect of energy transfer from lattice Gd³⁺ to activator Er³⁺ ions can be used for enhancement of solar cells efficiency. The general scheme showing the principle of operation of down-conversion layer based on Gd₂O₃:Er was presented. The concentration dependences of emission intensity and energy transfer efficiency were obtained. (paper)