New Composite Material Based on Heavy Concrete and Basalt-Boron Fiber for Neutron Radiation Shielding Properties

It is necessary to have reliable radiation protection for safe operation of different radiation sources. Radiation shielding properties have been studied for a long time both in our country and abroad. However, there is a strong necessity to develop new composite materials, which will provide protection against radiation and have improved mechanical and economic characteristics. The paper describes a new composite material for neutron radiation shielding properties based on heavy concrete with serpentinite aggregate and with basalt-boron fiber with different concentrations of fiber boron oxide for using in biological shielding in nuclear industry. Protective properties of the new composite material were investigated with different neutron sources: 1) neutrons with 14 MeV energy; 2) fast fission neutrons for U-235; 3) fast fission neutrons for U-235 after passing a water layer. The simulation of the neutron radiation in presented composite material with adding crushed stone aggregate and serpentinite aggregate is performed by Monte Carlo Serpent code. It is shown that basalt-boron fibers in concrete improve the protective properties of concrete against neutron irradiation for neutrons with different energies, but the most effective is the addition of a basalt-boron fiber in the case of thermal neutrons. This research was supported by Horizon 2020 ERA-NET Support Programme, Research Grant Agreement No 7.9-3/18/7 (“Development of Boron-Infused Basalt-Fiber Reinforced Concrete for Nuclear and Radioactive Waste Management Applications”). Implementation of activities described in the Roadmap to Fusion during Horizon 2020 through a joint programme of the members of the EUROfusion consortium (2014-2020), Work Package PMI. Also, this research was carried out with the financial support of the IAEA, within the terms and conditions of the Research Contract20638 in the framework of the Coordinated Research Project (CRP) “Accelerator Driven Systems (ADS) Applications and Use of Low-Enriched Uranium in ADS (T33002)’’ within the Project “The Two-Zone Subcritical Systems with Fast and Thermal Neutron Spectra for Transmutation of Minor Actinides and Long-Lived Fission Products”.

Dynamical fission following peripheral heavy-ion collisions

A closed-form theoretical approach describing in a single picture both the evaporation component and the fast nonequilibrium component of the sequential fission of projectile-like fragments in a peripheral heavy-ion collision is derived and then applied to the dynamical fission observed in the [Formula: see text]+[Formula: see text] semiperipheral collision at 35A[Formula: see text]MeV. Information on the reaction mechanism is obtained such as the opposite polarization effects and the estimate of the “formation-to-fast fission lifetimes” of the fissioning fragment.