This study investigates the luminescence properties of calcite within coral skeletons collected from Pulau Redang, Malaysia, focusing on the effects of gamma irradiation. Using Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectroscopy (EDX), X-ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), Raman Spectroscopy, and luminescence measurements, we examined structural and compositional changes in corals subjected to varying doses of gamma radiation. Present results indicate significant lattice disorder and structural breakdown at higher radiation doses, evidenced by increased porosity and altered elemental composition. Despite these changes, specific luminescent properties persisted, suggesting a degree of adaptability in the coral calcite. Thermoluminescence (TL) and photoluminescence (PL) analyses revealed that gamma irradiation created new electron traps, maintaining luminescence despite structural disruptions. The study highlights potential risks to coral structural integrity due to radiation while also revealing an inherent resilience in luminescent properties. These findings provide valuable insights into the effects of environmental stressors on coral calcite, informing conservation strategies aimed at preserving coral reefs under changing conditions.
Using irradiated doped-silica preforms from which fibres for thermoluminescence dosimetry applications can be fabricated we have carried out a range of luminescence studies, the TL yield of the fibre systems offering many advantages over conventional passive dosimetry types. In this paper we investigate such media, showing emission spectra for irradiated preforms and the TL response of glass beads following irradiation to an 241Am-Be neutron source located in a tank of water, the glass fibres and beads offering the advantage of being able to be placed directly into liquid. The outcomes from these and other lines of research are intended to inform development of doped silica radiation dosimeters of versatile utility, extending from environmental evaluations through to clinical and industrial applications.