Contribution of the Nucleation and Recovery of Disconnections to Shear Viscosity in Diffusional Creep

2021 ◽  
Author(s):  
Francis Delannay
Keyword(s):  
Shear Viscosity ◽  
Diffusional Creep

An Assessment of Red Cell Deformability Using a Simple Filtration Method

1979 ◽  
Author(s):  
M Drummond ◽  
G Lowe ◽  
J Belch ◽  
C Forbes ◽  
J Barbenel
Keyword(s):  
Cell Count ◽  
Shear Viscosity ◽  
White Cell Count ◽  
White Cell ◽  
Red Cell ◽  
Cell Deformability ◽  
Red Cell Deformability ◽  
Simple Method ◽  
Filtration Method ◽  
Significant Difference

We investigated the reproducibility and validity of a simple method of measuring red cell deformability (filtration of whole blood through 5 µ sieves) and its relationship to haematocrit, blood viscosity, fibrinogen, white cell count, sex and smoking. The mean coefficient of variation in normals was 3. 7%. Tanned red cells showed marked loss of deformability. Blood filtration rate correlated with haematocrit (r = 0. 99 on dilution of samples, r = 0. 7 in 120 normals and patients). After correction for haematocrit, deformability correlated with high shear viscosity, but not low shear viscosity, fibrinogen or white cell count. In 60 normals there was no significant difference between males and females, or smokers and non-smokers, but in 11 smokers there was an acute fall in deformability after smoking 3 cigarettes (p<0. 05). Reduced deformability was found in acute myocardial infarction (n = 15, p<0. 01) and chronic peripheral arterial disease (n = 15, p<0. 01). The technique is reproducible, detects rigid cells and appears useful in the study of vascular disease.

Macroscopic and molecular shear viscosity

1997 ◽  
Vol 167 (7) ◽  
pp. 721-733 ◽  
Author(s):  
Immanuil L. Fabelinskii
Keyword(s):  
Shear Viscosity

Kinematic Shear Viscosity of Water, Aqueous Solutions of Electrolytes, and Ethanol

2015 ◽  
Vol 60 (9) ◽  
pp. 854-860 ◽  
Author(s):  
V.M. Makhlaichuk ◽  
Keyword(s):  
Aqueous Solutions ◽  
Shear Viscosity ◽  
Solutions Of Electrolytes

Parallel Glide: A Fundamentally Different Type of Dislocation Motion in Ultrathin Metal Films

2003 ◽  
Vol 779 ◽  
Author(s):  
T. John Balk ◽  
Gerhard Dehm ◽  
Eduard Arzt
Keyword(s):  
Thermal Cycling ◽  
Grain Boundaries ◽  
Film Surface ◽  
Metal Films ◽  
Geometric Constraints ◽  
Film Stress ◽  
Diffusional Creep ◽  
Creep Model ◽  
Substrate Interface ◽  
Film Substrate

AbstractWhen confronted by severe geometric constraints, dislocations may respond in unforeseen ways. One example of such unexpected behavior is parallel glide in unpassivated, ultrathin (200 nm and thinner) metal films. This involves the glide of dislocations parallel to and very near the film/substrate interface, following their emission from grain boundaries. In situ transmission electron microscopy reveals that this mechanism dominates the thermomechanical behavior of ultrathin, unpassivated copper films. However, according to Schmid's law, the biaxial film stress that evolves during thermal cycling does not generate a resolved shear stress parallel to the film/substrate interface and therefore should not drive such motion. Instead, it is proposed that the observed dislocations are generated as a result of atomic diffusion into the grain boundaries. This provides experimental support for the constrained diffusional creep model of Gao et al.[1], in which they described the diffusional exchange of atoms between the unpassivated film surface and grain boundaries at high temperatures, a process that can locally relax the film stress near those boundaries. In the grains where it is observed, parallel glide can account for the plastic strain generated within a film during thermal cycling. One feature of this mechanism at the nanoscale is that, as grain size decreases, eventually a single dislocation suffices to mediate plasticity in an entire grain during thermal cycling. Parallel glide is a new example of the interactions between dislocations and the surface/interface, which are likely to increase in importance during the persistent miniaturization of thin film geometries.

Practical test methods for measuring the zero shear viscosity of bituminous binders

10.1617/14128 ◽  
2004 ◽  
Vol 37 (269) ◽  
pp. 360-364 ◽  
Author(s):  
J. De Visscher
Keyword(s):  
Shear Viscosity ◽  
Test Methods ◽  
Zero Shear Viscosity ◽  
Practical Test ◽  
Bituminous Binders

Prediction of Zero-Shear Viscosity of Linear Polybutadienes from the Crossover Point Using Doi-Edwards Theory

1988 ◽  
Vol 61 (5) ◽  
pp. 812-827 ◽  
Author(s):  
Ramesh R. Rahalkar ◽  
Henry Tang
Keyword(s):  
Shear Viscosity ◽  
Amorphous Polymers ◽  
Simple Expression ◽  
Crossover Frequency ◽  
Crossover Point ◽  
Zero Shear Viscosity ◽  
Plateau Modulus ◽  
Good Agreement

Abstract Based upon the Doi-Edwards theory, a simple expression has been obtained for zero-shear viscosity in terms of the plateau modulus and the crossover frequency. There are no adjustable parameters in the expression. The model is in very good agreement with the zero-shear viscosity values for linear polybutadienes, the typical discrepancy being ∼5–10%. If the model can be validated for other linear amorphous polymers, it may become possible to estimate the zero-shear viscosity by measuring a single Theological parameter (the crossover frequency).

scholarly journals Transport Coefficients of Hyperonic Neutron Star Cores

Universe ◽  
2021 ◽  
Vol 7 (6) ◽  
pp. 203
Author(s):  
Peter Shternin ◽  
Isaac Vidaña
Keyword(s):  
Thermal Conductivity ◽  
Neutron Star ◽  
Shear Viscosity ◽  
Transport Coefficients ◽  
Dense Matter ◽  
Baryon Number ◽  
Nucleon Nucleon ◽  
Total Thermal Conductivity ◽  
Nucleon Force ◽  
Density Region

We consider transport properties of the hypernuclear matter in neutron star cores. In particular, we calculate the thermal conductivity, the shear viscosity, and the momentum transfer rates for npΣ−Λeμ composition of dense matter in β–equilibrium for baryon number densities in the range 0.1–1 fm−3. The calculations are based on baryon interactions treated within the framework of the non-relativistic Brueckner-Hartree-Fock theory. Bare nucleon-nucleon (NN) interactions are described by the Argonne v18 phenomenological potential supplemented with the Urbana IX three-nucleon force. Nucleon-hyperon (NY) and hyperon-hyperon (YY) interactions are based on the NSC97e and NSC97a models of the Nijmegen group. We find that the baryon contribution to transport coefficients is dominated by the neutron one as in the case of neutron star cores containing only nucleons. In particular, we find that neutrons dominate the total thermal conductivity over the whole range of densities explored and that, due to the onset of Σ− which leads to the deleptonization of the neutron star core, they dominate also the shear viscosity in the high density region, in contrast with the pure nucleonic case where the lepton contribution is always the dominant one.

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