Pb diffusion in rutile

摘要: Diffusion of Pb was measured in natural and synthetic rutile under dry, 1 atmosphere conditions, using mixtures titanate or sulfide TiO2 as the sources diffusant. depth profiles were then with Rutherford Backscattering Spectrometry (RBS). Over temperature range 700–1100 °C, following Arrhenius relation obtained for rutile: D=3.9 × 10−10exp(−250 ± 12 kJ mol−1/RT) m2s−1. Results diffusion quite similar, despite significant differences trace element compositions. Mean closure temperatures calculated from parameters are around 600 °C grains ∼100 μm size. This is about 100 higher than determinations past field-based studies, suggesting that more resistant to loss through volume previously thought.