Simultaneous measurements of heat flow rate and thermal properties of nano boron trioxide under neutron irradiation at the low and high temperature

Abstract

In the present work, nano boron trioxide (B2O3) samples (purity of 99.5% and true density of 3.10 g/cm3) were irradiated by using neutron irradiation. Neutron irradiation of the samples was carried at the fast neutron flux 4·1012, 8·1012, 1.3·1013, 4·1014 n ⋅cm⁻2 s⁻1 and the neutron flux 1015 n ⋅cm⁻2 s⁻1 and energy of neutron flux E ≥ 1 MeV at room temperature to 350 h at the IBR-2 M pulsed reactor in Joint Institute for Nuclear Research, Dubna, Russia, was used. The unirradiation and after neutron irradiation the thermal kinetics and parameters changes with a differential mechanism. In the DSC curves at the low temperature for unirradiation and irradiation samples does not change. However, at the 100 ≤ T ≤ 900 K temperature range widely endo effects showed separation the water vapor, the absorbed water and hydroxide groups. Under neutron irradiation mechanism of separation of the hydroxide groups, water vapor and the absorbed water dependence of irradiation doses. The heat flow rate kinetics, specific heat capacity, thermodynamic function, degree of [OH] groups in the nano boron trioxide is a more completed.