Effect of particle size in the TL response of natural quartz sensitized by high dose of gamma radiation and heat-treatments

• Published in: Materials research (São Carlos, São Paulo, Brazil) Vol. 13; no. 2; pp. 265 - 271
• Main Authors: Carvalho Jr, Álvaro Barbosa de, Guzzo, Pedro Luiz, Sullasi, Henry Lavalle, Khoury, Helen Jamil
• Format: Journal Article
• Language: English
• Published: ABM, ABC, ABPol 01-06-2010; Associação Brasileira de Metalurgia e Materiais (ABM); Associação Brasileira de Cerâmica (ABC); Associação Brasileira de Polímeros (ABPol)
• Subjects: ENGINEERING, CHEMICAL; EPR spectroscopy; MATERIALS SCIENCE, MULTIDISCIPLINARY; METALLURGY & METALLURGICAL ENGINEERING; natural quartz; particle size; thermoluminescence; particle size; natural quartz; thermoluminescence; EPR spectroscopy
• ISSN: 1516-1439; 1980-5373; 1516-1439
• DOI: 10.1590/S1516-14392010000200023

This work investigates the effect of particle size in the thermoluminescence (TL) response of a quartz crystal that was initially crushed and classified into ten size fractions between 38 μm and 5 mm. Aliquots of each size fraction were sensitized with a dose of 25 kGy of γ rays and heat-treatments at 400 °C. TL glow curves of sensitized and non-sensitized samples were recorded as a function of different test-doses of γ rays. For the non-sensitized samples, the TL peak near 325 °C increases with the decrease in particle size. In the case of sensitized samples, a strong TL peak near 300 °C increases with the increase in particle size up to mean grain size equal to 304 μm. Above 304 μm, an abrupt reduction in the TL intensity is noticed for the sensitized peak. These effects are discussed in relation to the specific surface area of quartz particles and the intensity of the electron paramagnetic resonance signal of the E'1 center induced by the sensitization process.