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The technologies of knowledge representation and inference in an artificial intelligence system focused on the domain of nuclear physics and nuclear power engineering are considered. The possibilities of description logics and graph databases of nuclear knowledge for the generation of cognitive hypotheses, using in addition to deduction and other ways of reasoning, such as inductive inference and reasoning based on analogies, are discussed. The use of adequate description logic and measures of semantic similarity is substantiated. Interactive visual navigation and reasoning on the knowledge graphs are performed by means of special retrieval widgets and the smart RDF browser. Operations with semantic repositories are implemented on cloud platforms using SPARQL queries and RESTful services. The proposed software solutions are based on cloud computing using DBaaS and PaaS service models to ensure scalability of data warehouses and network services. Example of use of the offered technologies and software has been given.

Cascade reactors attract particular attention because of their capability of improving the parameters of pulsed reactors and achieving the feasibility of electronuclear facilities. The paper presents the results of three series of experiments on uranium-neptunium cascade assemblies at the Institute of Nuclear and Radiation Physics of the All-Russian Research Institute of Experimental Physics conducted in 2003–2004. The experiments confirmed theoretical conclusions on positive properties of cascade blankets and effectiveness of using neptunium-237 as a means of creating a one-sided connection between the sections.

The influence of preirradiation with an electron beam from a linear resonance electron accelerator in flowing argon on the structure and properties of the 1% Pt/H pentasil catalyst was studied. The support structure was studied by x-ray diffraction and low-temperature nitrogen adsorption. No changes in the crystal structure and pentasil specific surface area were observed in the irradiation dose range from 120 to 900 Mrad at an average electron energy of 7.7 MeV. The electron beam treatment resulted in a considerable increase in the catalytic activity of the Pt/H pentasil in gas-phase toluene hydrogenation as a model reaction. The results obtained by IR spectroscopy of adsorbed CO and X-ray diffraction data suggested that the increase in the catalyst activity after electron beam irradiation is due to changes in the size and charge of the Pt particles.

The objective of the study is the assessment of lifetime in the cohort of Mayak PA workers employed in 1948-1958 and exposed to incorporated Pu-239. The decrease of age at death 5.2 years among males and 6.6 years among females, and after the start of work--6.9 years among males and 7.7 years among females, with the increase of Pu-239 incorporation was shown. The association of the raised mortality rate from tumour causes is shown both among males and females, mainly due to malignant neoplasms of lung and live; which are organs of Pu-239 main deposition. For the first time related to Pu-239 incorporation decrease of age at death from tumour and non-tumour causes of main and secondary organs of deposition both among males and females was revealed. To assess the reduction of lifetime Years of Potential Life Lost (YPLL) were calculated per 10(5) person-years of potential life based on European gender standard. The calculations based on the obtained estimations showed significant dependence of YPLL on the level of Pu-239 incorporation. At that the main contribution to the increase of YPLL, i.e. to lifetime reduction, was due to radiation-induced decrease of the age at death as compared to radiation-induced increase of mortality rates.

The effect of electron irradiation on the properties of the systems 1% Pd/C, 1% Pd/Al2O3, and 1% Pd/TiO2 is studied in gas-phase and liquid-phase toluene hydrogenation. An increase in the irradiation dose to 120–900 Mrad increases the catalytic activity by a factor of 2–8 relative to that of the original system. XPS data for the Pd/C catalyst suggest that, after irradiation with high-energy electrons, the metal particles are stabilized on the surface of the carbon support, their degree of dispersion is increased, and their sintering is suppressed. These inferences are consistent with the observed changes in catalytic properties.

There is great interest in our and other contries in cascade blankets. Theoretical and design work has been done on cascade blankets but up to now no experimental work has been done. The first experiments in the world were performed at the All-Russia Reserach Institute of Experimental Physics in 2003–2004 on deeply subcritical uranium— neptunium assemblies. Three series of experiments on cascade and the corresponding single-section blanket models have been peformed. The experiments have confirmed the theoretical conclusions that cascade blankets have positive properties and that 237Np is effective in them; they have provided valuable experience in operating cascade setups with an electron accelerator. The good agreement between the measurements and the calculations has increased confidence in the computational results obtained for cascade blankets with real values of keff. The results of the second and third experiments and a general conclusion concerninig all three series of experiments are presented in this paper.

In the last ten years, Russia and other countries have been showing a great deal of interest in two-section blanket reactors with unilateral neutron coupling of the sections (cascade-type blankets). These setups are intended to operate in power and transmutation electronuclear facilities, for which they permit decreasing substantially the required power of the proton accelerator. Theoretical and design works have been done on cascade-type blankets, but until very recently there were no experimental works.

The results of the study of the interaction of genetic and radiation factors in the effects of radiation in humans exposed to external and (or) internal radiation are presented. In most cases, with relatively less radiation exposure genotypic differences in the effects of exposure were established to be absent. At high intensities of radiation exposure, however, these differences as a rule have reliable character. Interaction of genetic and radiation factors manifested in a wide range: from the mutual stimulation of primarily inactive factors to the higher than multiplicative one.

The polarization of the leading Λ hyperons produced on carbon and lead target nuclei by 4–10 GeV neutrons in the angle range Θ