2015-Sustainable Industrial Processing Summit
SIPS 2015 Volume 7: Ionic Liquids & Energy Production
| Editors: | Kongoli F, Gaune-Escard M, Mauntz M, Rubinstein J, Dodds H.L. |
| Publisher: | Flogen Star OUTREACH |
| Publication Year: | 2015 |
| Pages: | 310 pages |
| ISBN: | 978-1-987820-30-0 |
| ISSN: | 2291-1227 (Metals and Materials Processing in a Clean Environment Series) |
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Solidification as Deceleration of Processes by the 20 Orders of Magnitude Due to the Quantum "Freezing" of Atomic Degrees of Freedom
Alexei Potapov1; Valery Pavlov2;1INSTITUTE OF HIGH TEMPERATURE ELECTROCHEMISTRY, Ekaterinburg, Russian Federation; 2URAL STATE MINING UNIVERSITY, Ekaterinburg, Russian Federation;
Type of Paper: Regular
Id Paper: 181
Topic: 13
Abstract:
Close to the critical temperature, Тcr liquids have a viscosity of about 10-4 Pa·sec that corresponds to strain relaxation and the Maxwell structure time I„ = I•/G of the order of period of atom vibration I„ = I„0 ~ 10-13 sec; here G is the shear modulus. The fastest processes of diffusion, ionic electrical conductivity, etc. have approximately the same specific time near Tcr.
The opposite limit of the slowest processes, affordable for measuring, in the condensed substance can be achieved close to temperature Т0 ~ Tm/2, where Tm is the melting point. Here, the typical time for processes exceeds a year, that is why the measurements are very difficult and the experimental data are rare. The viscosity here reaches 1016 Pa·sec that is by the 20 orders of magnitude higher than that near the critical temperature (10-4 Pa·sec). The distinctive time for diffusion and other processes increases by the 20 orders of magnitude as well. This corresponds to the increase of the processes activation energy from zero to 46 RT because exp(46) = 1020.
If the liquid does not crystallize but vitrifies, then, within the considered temperature range, it passes such stages as "as water", "sun oil", "as dense honey", "pit asphalt", "deformable solid", "brittle solid".
A stage of consolidation is not taken into account in the traditional computer atomic model. Those processes, which in real situation last over a year, in model during computer experiment proceed for less than one nanosecond (10-9 s). Solidification, similar to the real one, was considered in the model on the assumption of that the quantum "freezing" atoms at the zero energetic level is motionless. The activation energy EA at cooling increases proportionally to the fraction of "freezing" atoms; and the solidification stages, specified above, from "as water" to "brittle solid" are present in the model. The melting point and hardness index accurately correlate with the "quantum degree" of the atomic system, in the simplest case - with the average atomic weight.
Keywords: consolidation, quantum "freezing" of atoms, activation energy, deceleration of atomic processes.