From the Editor-in-Chief

Yarmoshenko I.V.

MODELING IN DOSIMETRY AND BIODOSIMETRY, IS THERE ENOUGH KNOWLEDGE ABOUT THE STRUCTURE OF THE HUMAN BODY?

E. I. Tolstykh, P. A. Sharagin, E. A. Shishkina

The assessment of ionizing radiation doses is a necessary component of all radiobiological studies. Estimates of internal exposure doses based on model calculations are the most challenging ones. Dosimetric models describe the structures of the human body, their geometry, as well as the properties of mediums and the absorption of energy in them. Biokinetic models describe the turnover of radionuclides inside the body. Separately, there are models for biodosimetry that describe the movement of the target organ (T-lymphocytes and their precursors) through the body and the accumulation of radiation doses in them. The authors are engaged in modeling, in relation to one metal – bone-seeking strontium. The objective of the study is to analyze how data that were not included in the ICRP reviews and were not taken into account when creating dosimetric and biokinetic ICRP models can be used to improve models for dosimetry purposes. Three directions were chosen to discuss the completeness of the available information: (1) for biokinetic modeling – analysis of data on calcium content in the skeleton; (2) for dosimetric modeling, analysis of the anatomical and morphological characteristics of various skeletal bones, taking into account their changes with age; (3) for retrospective biodosimetry using data on the frequency of chromosomal translocations in T-lymphocytes – analysis of age-related dynamics and kinetics of T-cells. It has been shown that despite significant amount of accumulated measurement results, specific tasks for modeling any structures or processes are not always based on sufficient sets of experimental data. Thus, many model parameters were not determined precisely or were an expert estimate. The background information in the ICRP documents is not updated, and corresponds basically to the level of 1970s and 1980s, therefore, researchers need to pay attention to the search and accumulation of data underlying the modeling. When creating new and improving existing models, researchers form their own databases, which can become the basis of updated public Internet resources.

ENLIGHTENMENT AS A DRIVER OF NUCLEAR POWER DEVELOPMENT – KEY ASPECT IN ENSURING SUSTAINABLE DEVELOPMENT

N. V. Gorin, N. P. Voloshin, V. P. Kuchinov

The public attitude towards nuclear power, which is still largely non-positive, has been considered. It is noted that this attitude creates motivation for politicians to avoid topics that can complicate their struggle for electoral support and give political opponents an excuse to criticize them. This, in turn, complicates decision-making at the state level on the inclusion of nuclear power into the energy structure of countries as a source of electricity generation with a small carbon footprint. The global challenges of our time are discussed, such as
environmental pollution, increasing concentrations of greenhouse gases and climate changes associated with the civilization paradigm formed thousands years ago, which considers the environment as an unlimited source of raw materials and a place for waste disposal. It is shown that current transition from hydrocarbon energy to energy with a small carbon footprint should include nuclear power as a component independent of weather conditions and time of day. It is demonstrated that the development of nuclear power requires fundamental changes in public attitude towards nuclear power, which is impossible without appropriate outreach and enlightenment which should brgin from school.

MINIMUM ACHIEVABLE VALUES OF WASTE-SPECIFIC RATES AT PWR AND BWR NUCLEAR POWER PLANTS

D. D. Desyatov, A. A. Ekidin, V. A. Shatalin

The article substantiates the numerical values of the waste-specific rates of nuclear power plant radioactive waste generation per unit of electricity produced, which correspond to the basic principle of the INRPO methodology for the sustainability of national nuclear energy The analysis of the data set on waste-specific rates made it possible to rank the practices of nuclear power plants with radioactive waste in the categories of “best”, “sustainable” and “worst”. Linear trends in the dynamics of specific activity indicators show a decrease for all types of reactor facilities and for all categories of RW. There is a tendency to increase the RW of class in the dynamics of waste-specific volume for BWR and all types of nuclear facilities in general. The category of “best” practices for the management of radioactive waste mainly includes PWR nuclear power plants, and BWR nuclear power plants are in the category of “worst”. The minimum achievable level of specific RW indicators at PWR and BWR nuclear power plants of categories , , , are equal 1,09∙10-1 (7,03∙10-4); 1,07∙10-3 (8,02∙10-3);1,55∙10-3 (6,75∙10-6); 2,53∙10-6 (2,63∙10-4) GBq/Gwt·h (m3/Gwt·h).

INVERSE PROBLEMS OF SPETROSCOPY AND SPECTROMETRY IN APPLIED RESEARCH

I. N. Ogorodnikov

A review of some practical methods for solving inverse problems of spectroscopy and spectrometry, prepared by the author while teaching a course on inverse problems of physical diagnostics for master’s students at the Institute of Physics and Technology of the Ural Federal University, studying in the direction of “Nuclear Physics and Technology”. Additional theoretical materials and technical information necessary for the practical implementation of the considered methods for solving and regularizing inverse problems are presented. The hardware aspects of spectroscopic practice (spectrum, hardware function (AF), calibration polynomial, etc.) are discussed. Mathematical models and methods for solving and regularizing inverse problems are considered: A. N. Tikhonov’s method of generalized discrepancy and regularization for energy-non-invariant AF; method of regularization of discrete Fourier transform for energy-invariant AF; method for reconstructing the spectrum of a multisphere spectrometer using a stochastic algorithm for parameterizing the model curve. All methods for solving and regularizing inverse problems are presented in relation to freely distributed software (SciLab ver.6.1). The author’s software for demonstrating the capabilities of the methods discussed is also distributed freely in the form of a file archive containing the main programs for implementing the algorithms, examples of solving model problems, libraries of additional routine procedures, as well as the source texts of all used programs.

GAMMA RADIATION BUILDUP FACTOR: HISTORY, CURRENT STATE, PROSPECTS

M. V. Zhukovsky

A review of original works devoted to the development of the theory and practical implementation of calculations of buildup factors taking into account the influence of scattered -radiation on the dose rate behind protective barriers or inside them is carried out.
The influence of various processes of interaction of photon radiation with matter, leading to the appearance of scattered -radiation, is considered. The history of the origin of the term “buildup factor” is presented, a description is given of the first fundamental works on
calculating the values of buildup factors for various shielding materials, energies and geometry of -sources. A review of the work of Taylor, Berger, Capo, Trubey and others on the selection of approximating functions that describe the dependence of buildup factors on
the properties of the medium and radiation energy is given. For the Capo and Trubey approximating functions, a detailed description of which is not available in the Russian literature, numerical values of the parameters used for calculations are given. A detailed review of the history of the development of the geometric progression method for calculating the buildup factor of -radiation is given. This method has not previously been described in the Russian literature and has not found practical application. Descriptions of software products designed for calculating buildup factors using the geometric progression method are given. Possible directions for the development of theory and practice of methods for calculating buildup factors are shown.