کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
4713985 | 1638468 | 2007 | 10 صفحه PDF | دانلود رایگان |
The paper discusses a model of viscosity η of glassforming melts in an attempt to predict the dependence of η on temperature T and on pressure P. The equation, derived here, describes with excellent accuracy all existing experimental viscosity data including those of glassforming melts, igneous materials and polymers. It is demonstrated that the activation energy E(Tg) can be expressed through the glass transition temperature Tg as E(Tg) = εRTg where εR = 260 ± 10% in J/(mol K). The dependencies of the parameters of the viscosity equation are discussed for certain geoscientifically relevant systems.According to the model the relaxation time of the mantle is about 32 000 years, a time suspiciously close to the period during which the direction of magnetic poles changes.
Journal: Journal of Volcanology and Geothermal Research - Volume 160, Issues 1–2, 1 February 2007, Pages 165–174