Trace element diffusivities in bone rule out simple diffusive uptake during fossilization but explain in vivo uptake and release
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چکیده
منابع مشابه
Trace element diffusivities in bone rule out simple diffusive uptake during fossilization but explain in vivo uptake and release.
Diffusion rates of numerous trace elements in bone at 20 °C were determined using laser-ablation inductively coupled plasma mass spectrometry analysis of experimentally induced diffusion profiles. Diffusivities are about 1 order of magnitude slower than current semiquantitative geochemical views and about 1.5 orders of magnitude faster than indirect radiotracer estimates. Intrabone volume diffu...
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Models of diffusion-limited uptake of trace elements in fossils and rates of fossilization
Many fossils are assumed to take up trace elements by a process of combined diffusion plus adsorption (DA), yet in principle composition profiles can be explained by several different diffusion-limited processes, including diffusion plus reaction or recrystallization (DR) and double-medium diffusion (DMD). The DA and DMD models are supported by REE and U composition profiles across fossil teeth...
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ژورنال
عنوان ژورنال: Proceedings of the National Academy of Sciences
سال: 2012
ISSN: 0027-8424,1091-6490
DOI: 10.1073/pnas.1209513110