The paper considers the results of a study of the decomposition of surfactants in the unbalanced waters of nuclear power plants by corrective treatment with hydrogen peroxide followed by heating. It proposes a method of determining the type and concentration of surfactants in aqueous solutions based on the method of high-performance liquid chromatography in tandem with mass spectrometry (HPLC-MS). The dependences of the purification efficiency of the solution on the initial concentration of surfactants, time and temperature as well as on the presence of an additional contaminant (potassium permanganate) are investigated. It is shown that in order to meet the requirements of regulatory documents with a conservative approach the efficiency of surfactant purification should be at least 81% when evaporating the cubic residue before cementing to 150 g/l and at least 95 % when evaporating to 450 g/l. Decomposition of complexing agents is shown to occur during processing in the temperature range of 80-100 degrees Celsius when hydrogen peroxide is dosed into aqueous solutions. The surfactant concentration reaches a value of 62 % at temperatures of 80 C and above which corresponds to the surfactant content in the cube residue not exceeding the value of 1 % (without conservative approach) after 4 hours of treatment. Dosing of potassium permanganate into the purified water allows to achieve virtually 100% purification from surfactants, without resorting to heating the water to boiling point. The efficiency of purification from surfactants to the level of complexing substances in the cubic residue in the range below 1 % is achieved by dosing potassium permanganate 70 minutes after the start of the experiment, and when heated to 100 C – in less than 40 minutes. The results obtained can be used to substantiate the safety of radioactive waste management technologies used in nuclear energy.

The article considers the final stage of emergency development associated with the transport unit overturning with a small-sized nuclear power plant. Mathematical modelling allowed to obtain information about possible consequences. Among the most serious foreseeable damages are violations of the thermal protection coating in the area of the tip and bottom of the unit, which is a part of the separating head unit. To assess the unacceptability of this or that damage, the method of calculation of aerodynamic characteristics of flows near the surface with a defect was used. In case of insignificant damage, it is possible to consider further use of the unit for its intended purpose, which may be important in the threatened period for states with a limited number of such products.

The paper considers the influence of an anthropogenic acoustic background on the formation of the
γ-spectrum recorded by a xenon γ-spectrometer. The presence of an anthropogenic acoustic background is shown to deform the spectrum significantly producing a broadening of the total absorption peak and a decrease in its amplitude compared to the spectrum obtained in the absence of acoustic load. Such deformation of the total absorption peak will lead to deliberately underestimated assessments of the parameters of radioactive contamination of the environment in conditions of radiation accidents, which will ultimately lead to wrong decisions in ensuring radiation safety of personnel and population located near nuclear facilities where the radiation accident occurred. The observed deformation of the
γ-spectrum required a protective covering of the γ-spectrometer with porous rubber used to absorb the acoustic load. The results were generally satisfactory, but the weight of the γ-spectrometer and its dimensions increased significantly. As an alternative protection the authors propose to use a metal capsule with thin walls, placing the detector in it and pumping out the air from it, i.e. providing the xenon γ-spectrometer protection instead of porous rubber, «vacuum shell» which is formed in the absence of an elastic medium – air in the capsule. This method of protection is characterised by simplicity, accessibility and does not require large financial outlays.

A gradient method of structural inhomogeneities identification in the objects of industrial equipment and products control based on the analysis of electric potential distribution inside a single reflex is developed. The computational and graphic method is applied to analyze the results of electrical control of NPP equipment during its manufacture. The research objective under consideration is to determine the degree of reproducibility of electrical inspection results and to develop for this purpose a universal digital identifier of structural inhomogeneities. Single reflexes are characterized by internal pressure and distribution of electric potential, which has a gradient. Single reflexes on potentiograms are isolated by electrophysical chromatography with the help of double amplitude discrimination using developed program codes. The emergence of potential distribution patterns on the surface of the controlled product is associated with the presence of inhomogeneous fields of internal stresses and deformations in it. To determine the local value of internal pressure in structural inhomogeneities, the value of energy density was estimated. This estimation for single reflexes is obtained using the value of electron density in metals and alloys. The magnitude of the gradient corresponds to the electric field strength around the reflex. On the surface, a single reflex represents a figure of concentric hexagons or other geometric figures. In the volumetric image, the reflex has the form of a pyramid with a certain figure at its base. The hexagonal shape of the reflex is associated with a quasi-equilibrium distribution of normal and tangential stresses around the point heterogeneity. The value of internal pressure in steels for the fixation level in the interval (0≤ SLS <1) is close to the strength limit, for the interval of negative values (-0,7 ≤ SLS < -0,4) – to the yield strength.

The objective of this article is to study the issues of mathematical elastic-plastic models of a material taking into account the available rheological properties and their connection with the finite element model in modern software complexes of numerical modeling. The article presents the results of numerical modeling of deformation processes of materials, deformation diagrams of materials, analytical methods for approximating deformation diagrams. One of the analytical methods of the restoration of the Prandtl diagram is presented, a method using the Ramberg-Osgood coefficient, which includes the values of reference parameters about the material, such as elastic modulus, tensile strength, yield strength, fracture criteria, elongation and relative thinning. The description and results of numerical modeling of the material destruction, modeling of plastic instability preceding the destruction, and the results of a study to establish grid convergence are presented. The procedure of verifying the numerical model of the material, which is a calibration tests of sample uniaxial rupture model parameters, is given.

Many research staffs and groups have paid considerable attention to the issues of noise analysis and control of nuclear power plant operation parameters. This is reflected in the scientific environment in the form of numerous publications, monographs, articles, and reviews devoted to the study of noise components of various variation signals of reactor plants. However, despite the advanced theoretical works on this topic, applied research, i.e. direct reactor experiments, remains aside from the interests of both local and foreign scientists. The need of practical research is due to the complexity of interpretation of a variety of anomalies detected by noise methods, as well as the need to fine-tune various models. In addition, the spectral images of equipment can differ significantly not only between different designs of reactor plants, but also within the same-type units at one NPP. These problems cannot be solved by theoretical or computational methods alone, or by using simulation modeling. The situation is complicated by the fact that noise studies are a complex task both in terms of selecting noise data sources and interpreting the obtained information. Probably, these reasons explain the significant decrease of interest to experimental works on noise subject at various reactor plants both in the world practice and in Russia. The paper briefly discusses some possibilities of methods of neutron-noise control of cores aimed at improving the reliability and safety of NPPs. In addition, the article considers ways to reduce the labor intensity of their use for the earliest possible detection of anomalous condition of various equipment.

The self-sustained nuclear fission chain reaction is based on the probabilistic nature of fundamental physical processes. The measure of the dynamics of these processes (state identifier) is taken to be reactivity as a special physical property of the medium or technical system. The paper proposes to attribute reactivity to the class of random functions with zero mathematical expectation in the stationary critical state. Fluctuations with respect to zero value are perceived as a result of external factors causing an instantaneous response of the core of reactor plants operating at the installed power for the main part of the operating time. This definition is sufficient to develop methods of technical diagnostics based on perturbations of the reactivity of the core. The reactor core is considered as a stochastic object that is kept within the normative field of its design and regime characteristics. According to the archive data of reactivity ‘measurements’, it is possible to correlate to certain states of the reactor core the fragments of stochastic time series, which would serve as identifiers of these states. The set of such fragments (tests) constitutes a library of NPP operation experience. In the present work, the effects of an external Poisson perturbation of reactivity and the classification of neutron density modulations arising therefrom are considered in the framework of the one-group kinetics model. The reflection in the probabilistic characteristics of neutron density of random static and dynamic regime factors through reactivity is perceived as evidence of generation of defectiveness of the reactor core. The deterministic component of neutron density is described quite accurately by the equations of kinetics and corresponds to the trend of the mathematical expectation of reactivity with respect to zero value. A procedure of processing the data of neutron flux control equipment and reactor intrinsic control system is proposed, which includes formation of a library of test perturbations on the basis of archived data; analysis of responses by the Kolmogorov-Smirnov criterion of agreement between the empirical distribution functions of the current sample of empirical data and those calculated by the equations of kinetics on the basis of the library of perturbations.  It is argued that the proposed procedure is a means of identifying the defect level of the core and can also be used as an event simulator in deep learning of a classifying neural network.  The results refer to the achievements of neutron-noise diagnostics.

The article describes the result of the research aimed at the development of a portable complex for carrying out rapid, non-disassembly diagnostics and calibration of torque limiters of motor operated valves at the place of their operation (multimedia training program). The concept and methodology of electric drive calibration at the place of its installation on the motor operated valves is described. The description of the software and hardware complex realizing this concept is given. The main test results of the complex which showed its applicability for motor operated valves diagnostics at NPPs are described. Statistical tests are performed in order to develop and certify measurement techniques. The uncertainty of the electric drive calibration result which is introduced by the calibration procedure itself is analysed. It is shown that the influence of torque sensor installed with the help of specially designed tooling between valve and electric drive is insignificant and affects only minor diagnostic parameters. Thus, the possibility of combining the operations of the basic drive testing and technical diagnostics of an electric drive has been confirmed. The obtained test results are used for the development and metrological certification of the methodology of direct and indirect torque measurement of the motor operated valves at the place of its operation

Sustainable economic development based on technological independence and technological leadership is largely realized in the real sector. One of the leading positions in the world market is occupied by the nuclear energy of Russia. Enterprises of the real sector of the nuclear industry economy are located in the cities where Rosatom State Corporation facilities are present. Concentration of resource potential and its effective development requires personnel provision, and it largely depends on the living conditions and quality of life provided by the territory. Creating a comfortable urban environment for the development of atomic cities requires an influx of significant investments. This article discusses the features, problems and prospects for the development of one of the 29 atomic cities, the city of Volgodonsk, in the context of agglomeration processes and the formation of a new Volgodonsk agglomeration