Phase transformation of the corrosion layers on nuclear fuel cladding. Raman spectroscopy study.

The goal of this work was the phase analysis of corrosion layers on zirconium alloys. In the environment of nuclear reactors, zirconium alloys are covered with a protective layer of zirconium oxide, which occurs in two crystalline modifications - monoclinic and tetragonal. The distribution of these phases in the corrosion layer can affect the overall corrosion rate. Raman spectroscopy was used to determine the composition of the corrosion layers. The use of this method is advantageous because the monoclinic and tetragonal phases can be easily distinguished in the spectra of the corrosion layers. In total, samples of two alloys were measured. The samples were pre-exposed at 360 °C in Li+ containing water (70 mg/l Li as LiOH) . Exposure times were between 21 d and 231 d, so the series contained both pre- and post- transition samples. The relative proportion of the tetragonal phase decreases significantly after the transient. It has also been found that the corrosion layers are highly heterogeneous in terms of the distribution of crystalline modifications.

Synthesis and Characterisation of Pure Zirconium Oxide (ZrO2) Nanoparticle by Conventional Precipitation Method

In this paper, the synthesis of Zirconium oxide (ZrO2) nanoparticles was carried out by the Conventional precipitation method. Ultraviolet, visible spectroscopy (UV-Vis), and dynamic light scattering analysis (DLS) were performed to find the particles' bandgap and size. Fourier transform infrared spectroscopy (FT-IR) observed the characteristic bands of Zirconium oxide nanoparticles. Dynamic light scattering analysis showed that the size of the particle was found to be 119 nm.

Using of mechanoactivation for preparation of cerium-containing solid solutions based on zircon

Solid-phase synthesis of cerium-containing solid solutions based on ZrSiO4 was described. The synthesis was carried out using mechanical activation of a mixture consisting of zirconium oxide and hydrated amorphous silica with the addition of cerium oxide at a molar ratio of ZrО2:SiО2:CeО2 equal to 0.95:1.00:0.05. The mechanically activated in a centrifugal planetary mill mixture of reagents was calcined in the temperature range of 1200–1600 °C for 3 hours, which was accompanied by the essentially complete synthesis of zircon. The cerium content in the zircon structure was calculated from X-ray powder diffraction data.