Study of the Initial Stages of Sintering Solids by Viscous Flow, Evaporation‐Condensation, and Self‐Diffusion

1955 ◽  
Vol 26 (10) ◽  
pp. 1205-1212 ◽  
Author(s):  
W. D. Kingery ◽  
M. Berg
Keyword(s):  
Viscous Flow ◽  
Self Diffusion

scholarly journals Mechanics of Supercooled Liquids

2014 ◽  
Vol 81 (11) ◽  
Author(s):  
Jianguo Li ◽  
Qihan Liu ◽  
Laurence Brassart ◽  
Zhigang Suo
Keyword(s):  
Viscous Flow ◽  
Chemical Potential ◽  
Relative Rate ◽  
Diffusion Flux ◽  
Continuum Theory ◽  
Supercooled Liquid ◽  
Supercooled Liquids ◽  
Thermodynamic Consideration ◽  
Self Diffusion ◽  
Molecular Dimension

Pure substances can often be cooled below their melting points and still remain in the liquid state. For some supercooled liquids, a further cooling slows down viscous flow greatly, but does not slow down self-diffusion as much. We formulate a continuum theory that regards viscous flow and self-diffusion as concurrent, but distinct, processes. We generalize Newton's law of viscosity to relate stress, rate of deformation, and chemical potential. The self-diffusion flux is taken to be proportional to the gradient of chemical potential. The relative rate of viscous flow and self-diffusion defines a length, which, for some supercooled liquids, is much larger than the molecular dimension. A thermodynamic consideration leads to boundary conditions for a surface of liquid under the influence of applied traction and surface energy. We apply the theory to a cavity in a supercooled liquid and identify a transition. A large cavity shrinks by viscous flow, and a small cavity shrinks by self-diffusion.

Viscosity and self-diffusion in benzene-cyclohexane mixtures

1964 ◽  
Vol 17 (5) ◽  
pp. 516 ◽  
Author(s):  
DA Collins ◽  
H Watts
Keyword(s):  
Activation Energy ◽  
Diffusion Coefficient ◽  
Viscous Flow ◽  
Mole Fraction ◽  
Excess Volume ◽  
The Self ◽  
Excess Viscosity ◽  
Self Diffusion ◽  
Mole Fraction Range ◽  
Self Diffusion Coefficient

The self-diffusion coefficient of benzene in benzene-cyclohexane mixtures was measured at 15�, 25�, and 35�. Viscosities of the mixtures were measured at the same temperatures. The diffusion coefficient is a maximum, while the viscosity is a minimum at a mole fraction of benzene between 0.6 and 0.8. The activation energy for viscous flow is a minimum in the mole fraction range 0.6-0.8 of benzene. The excess viscosity and the excess activation energy of viscous flow are minimal at a mole fraction 0.5, the same composition at which the maxima occur in excess volume and heat mixing. The product Dn is a linear function of mole fraction.

Permeability in Relation to Viscosity and Structure of Rubber

1942 ◽  
Vol 15 (3) ◽  
pp. 537-544 ◽  
Author(s):  
Richard M. Barrer
Keyword(s):  
Viscous Flow ◽  
Thermal Energy ◽  
Diffusion Constant ◽  
The Self ◽  
Self Diffusion ◽  
Functional Relations ◽  
Diffusion Media ◽  
Entropy Of Activation ◽  
Arrhenius Energy ◽  
And Diffusion

Abstract Some properties of flow of solutes in and through rubbers are outlined. These properties indicate that, due to fluctuations of thermal energy, activated zones exist in certain polymers, of which viscous flow and diffusion are a consequence. A simple statistics of activated zones has been given, and from it equations are obtained for ΣN, D, Ds, and η, denoting respectively the total number of activated zones in rubber, the diffusion constant of simple solutes in the polymer, the self-diffusion constant of rubber, and its viscosity. Functional relations are predicted between log Do, log ηo, or ΔS* (the entropy of activation) and the Arrhenius energy of activation for diffusion or viscous flow. The available data clearly demonstrate this relationship. They also indicate no discontinuity between rubbers and liquids as diffusion media.

Viscous flow and self-diffusion in densely and loosely packed metallic melts

2021 ◽  
Vol 103 (6) ◽  
Author(s):  
S. Nell ◽  
F. Yang ◽  
Z. Evenson ◽  
A. Meyer
Keyword(s):  
Viscous Flow ◽  
Self Diffusion ◽  
Metallic Melts

Self-diffusion study of bile salt-monoolein micelles determination of the intermicellar bile salt concentration

1983 ◽  
Vol 80 ◽  
pp. 315-323 ◽  
Author(s):  
Marc Lindheimer ◽  
Jean-Claude Montet ◽  
Roselyne Bontemps ◽  
Jacques Rouviere ◽  
Bernard Brun
Keyword(s):  
Bile Salt ◽  
Salt Concentration ◽  
Diffusion Study ◽  
Bile Salt Concentration ◽  
Self Diffusion
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