Advanced Materials Research Vol. 1084

Abstract: In this article the mathematical model of non-stationary hydraulic processes occurring in gas centrifuge cascades for uranium enrichment is described. This model simulates the technological equipment behavior in standard and emergency situations for possible operational and disturbing influences. Also, the algorithm of differential equations system solving for this model is represented.

Abstract: This paper is devoted to one of the most urgent problems in the automation of fluorine production (FP) processes: the development of a dynamic model of the hydrodynamic regime. The paper suggests a dynamic model represented in the form that provides the effective use of up-to-date methods of synthesis and analysis for control algorithms. The model is a set of dynamic models of individual units and devices that have a significant impact on the processes in the technological scheme.

Abstract: The structure of the estimators is similar to the recursive kernel estimators of a density function and its derivative. The estimators have been constructed using a single realization of Poisson process on a fixed time interval. Mean-square convergence has been proved in a scheme of series. Simulation studies have been carried out to illustrate the convergence.

Abstract: The computer model of emergency shutdown (ESD) system of Tokamak has been developed. Xcos extension of the package Scilab of linux operating system was used for developing the model. The simulated system monitors the most ultimate in terms of the integrity of the preproduction equipment and personnel safety parameters and provides an opportunity to prevent accidents. In the accidents occur the system executes algorithms of protective effects providing the complex transfer to a safe state, which allows to reduce consequences of possible accidents.

Abstract: High-resolution X-ray tomography, also known as micro-computed tomography (micro-CT) or microtomography, is a versatile evaluation technique, which extends application in various fields including material science. Micro-CT is a suitable method for quantitative and dimensional materials characterization. Needless to say, the accuracy of the method and applied equipments – micro-CT scanners – should be assessed to obtain reliable, solid results. In this paper, the performance of a micro-CT scanner as a visualization system is discussed. Quantitative parameters of image quality and visualization systems as well as methods to obtain their numerical values are briefly described. The results of experiments carried out on in-house made micro-CT scanner TOLMI-150-10 developed in Tomsk Polytechnic University are presented.

Abstract: This paper presents the results of designing experimental setups for the X-ray visualization. The setups allow to obtain the projection of two-dimensional images and sinograms that are used to restore the tomographic cross-sections. The results of the computing of the dose burden are supplied. The low values of the equivalent doses, received in the experiment, are analyzed.

Abstract: The problem of non-proliferation of special nuclear materials remains actual, so it is required to study new technologies and perspective materials for ensuring radiation monitoring at checkpoints. In this article application of radiation portal monitors of special nuclear materials is reviewed considering features of physical protection systems of nuclear facilities. Russian and foreign experience of radiation portal monitors design is summarized. A number of means to improve design of radiation portal monitors of special nuclear materials were offered. Also problem and important role of materials research is indicated considering development of radiation monitoring technologies.

Abstract: Spatial distributions of a potential established inside a crystal by an externally applied potential are investigated theoretically in Pd and PdH. The calculations were performed in the framework of the linear-response approach with full inclusion of the electron band structure obtained within a self-consistent pseudopotential scheme. Analysis shows that in clean palladium the potential amplitude is maximal at the octahedral sites of the fcc lattice where the hydrogen ions predominantly reside. On the other hand the corresponding amplitude is significantly lower at the palladium ion positions. We observe drastic modifications in the screening properties in Pd upon hydrogen absorption. Nevertheless, the potential amplitude in PdH is also small at the Pd sites, whereas that at the H sites is significantly larger. However, in PdH the H ions are located at places where a local shallow minimum in the induced potential amplitude is observed. These results only slightly depend on the magnitude of the momentum transfer.

Abstract: The paper performs the distribution mapping of ion formation intensity based on the contamination map around Fukushima Daiichi Nuclear Power Plant (FDNPP). The study compares the ion formation intensity in soil after Fukushima and Chernobyl nuclear accidents.

Abstract: SOCRAT-BN code is developed for the analysis of design and beyond design basis accidents at sodium cooled fast reactors. To simulate the behavior of the coolant in the reactor core heat transfer and friction in rod bundle geometry are required to consider. The article describes the validation of the code SOCRAT-BN on the experiment with fuel rod imitators in the triangular geometry with wire-wound taking into account experiment and some code model uncertainties.