Radiation-thermal oxidation of beryllium in contact with water at temperatures T = 473…773 K under the combined effect of temperature and gamma radiation has been studied by methods of infrared and optical spectroscopy. The formations of an oxide layer on the surface of beryllium were traced from the infrared and optical reflection spectra. In the IR spectra, the broadening of the oxide layer on the Be surface (T = 573 K) was revealed with an increase in the absorbed dose by ~ 2.5 times, which is associated with inhomogeneities caused by gamma irradiation. According to the optical reflection spectra of the surface of radiation-thermally oxidized Be, it was revealed that in the region of the edge of short waves λ ≤ 250 nm, an absorption band is observed, the intensity of which increases with increasing contact time and indicates the formation of an oxide layer

High-density polyethylene sheets (HDPE), HDPE/GaAs and HDPE/ GaAs<Te>  composites with GaAs and GaAs<Te> semiconductor fillers were studied by X-ray diffractometry at room temperature. The degree of crystallization of these samples was calculated and it was determined that the inclusion of fillers in the polymer matrix (x=1-10% composite) leads to an increase in the degree of crystallization by 1.3-1.4 times. The obtained results are explained by the change of the upper molecular structure of the polymer.