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Shear Viscosity for a Debye-Hückel Plasma P. Qu A A S Institut für Theoretische Physik der Technischen Universität Dresden (Z. Naturforsch. 23 a, 757—760 [1968] ; received 24 February 1968) The Kubo formula for the shear viscosity of a Debye-Hückel plasma is evaluated by an extension of ERNST'S method. In the main the result can be shown to be equivalent to the result derived by BRAUN from the LENARD-BALESCU equation with the CHAPMAN-ENSKOG method. Moreover a correction of BRAUN'S result can be given as caused by the particle interaction. 1. Introduction

Shear Viscosity of the Homologous Series of wCHBT (n = 0 -f 12) in the Isotropic and Nematic Phases J. Jadżyn, R. Dąbrowski3, K. Glumiak, and G. Czechowski Institute of Molecular Physics, Polish Academy of Sciences, Smoluchowskiego 17, 60-179 Poznan, Poland a Institue of Chemistry, Military University of Technology, Kaliskiego 2, 01-489 Warsaw, Poland Reprint requests to Prof. J. J.; Fax: 4861-86 84 524; E-mail: jadzyn@ifmpan.poznan.pl. Z. Naturforsch. 55a, 6 3 7 - 6 4 0 (2000); received April 19, 2000 The paper presents results of shear viscosity

American Mineralogist, Volume 94, pages 975–980, 2009 0003-004X/09/0007–975$05.00/DOI: 10.2138/am.2009.3092 975 Shear viscosity and diffusion in liquid MgSiO3: Transport properties and implications for terrestrial planet magma oceans Dean nevins,1,* Frank J. spera,1 anD Mark s. Ghiorso2 1Department of Earth Science, University of California, Santa Barbara, California 93106, U.S.A. 2OFM Research-West, 7336 24th Avenue NE, Seattle, Washington 98115, U.S.A. abstract Molecular dynamics simulations using a pair-wise additive potential are implemented to investi

Abstract

The aim of this paper is to present a new phenomenological rheological model suitable for the description of a wide class of viscoelastic fluids. Classical phenomenological models predict the relation shear viscosity vs. shear rate (or shear stress) for shear-thinning (or thickening) materials exhibiting smooth monotonous passage from the first - upper (lower) - Newtonian plateau to the second - lower (upper) - one. However, present state of non-Newtonian materials used in practice (ranging from aqueous surfactant solutions, bituminous materials, associative polymers, polymer thickeners, lacquers and gels, to some special disperse systems, etc.) evokes the need to describe this - for many materials non-monotonous - relation in the corresponding way, i.e. through the sufficiently simple phenomenological model with a moderate number of parameters. A six-parameter model enabling description of not only monotonous but also non-monotonous course of shear viscosity function against shear rate (stress) is proposed including physical characterisation of the parameters. This model describes not only extreme points (maximum or minimum) but also a possible appearance of intermediate Newtonian plateau or its indication. The meaning and influence of the individual six parameters is documented on the experimental data published in the literature. There is a good agreement of the model proposed with many different experimental data representing different rheological behaviour. The applicability of this model for a wide class of viscoelastic materials is its principal advantage over the hitherto published phenomenological models.

Abstract

The rheological behaviour of PVC plastisols composed of a blend of suspension and micro-suspension resins in different proportions was investigated. The present work was mainly focused on the variation of the zero shear viscosity versus the concentration of the extender resin. Hence, the packing fraction Fm was evaluated using the Krieger-Dougherty equation. These experiments confirmed the major influence of particle size distribution concerning the decrease of viscosity for concentrated suspensions. In addition, a model based on the porosity model developed by Ouchiyama et al. (Ouchiyama N, Tanaka T: Porosity estimation for random packings of spherical particle”, Ind. Eng. Chem. Fundam. 23 (1984) 490-493) to predict the packing fraction in the case of multimodal lattices was successfully applied to our PVC plastisols formulations.

Zeitschrift fur Physikalische Chemie Neue Folge, Bd. 156, S. 331-337 (1988) © by R. Oldenbourg Verlag, Munchen 1988 - 0044-3336/88 $3.00 -I- 0.00 Shear Viscosity and Structural Relaxation in Dense Liquids* ** Anthony J. C. Ladd W. Edward Alley Bernl J. Alder Lawrence Llvermore National Laboratory Llvermore, California 94550 The long-time decay of the shear-stress autocorrelation function 1n a dense hard sphere fluid. Is shown to be quantitatively related to the decay of correlations between the orientation of "bonds" connecting colliding pairs of particles. As a

J. Non-Equilib. Thermodyn. Vol. 14 (1989), pages 69-77 Correlation Method for the Shear Viscosity off Fluid Mixtures at Moderate Densities R. Castillo, S. Castaneda Inst, de Fisica, Universidad Nacional Autonoma de Mexico, Mexico City, Mexico Received 23 April 1987 Registration Number 434 Key Number 2201123 Abstract A method to predict the shear viscosity of fluid mixtures is described. The method relies on the results of the Revised Enskog Theory for hard-sphere fluid mixtures and the use of temperature and density dependent diameters to model each species of

Abhangigkeit der ersten Normalspannungsdifferenz von Silikonolen von der Nullviskositat und dem Molekulargewicht Dependance of the first normal stress difference of silicone oils on zero-shear viscosity and molecular weight Es w urden die visk oelastisc hen Eigensc haften von Si l ik onolen mit Molgew ic hten von 68 bis 164 kgj mol (M 20 000 bis 500 000) untersuc ht. Die Abhangigk eit der ersten Normalspannungs­ diff erenz von der Nul lviskositat und dem Mol­ gew ic ht w urde experimentel l und durc h Ableiten der Normalspannungs-Masterk urve erhalten

for the complex viscosity of polymer melts[J]. Rheologica Acta, 1988, 27(4):384-396. [11] Mckenna G B, Hadziioannou G, Lutz P, et al. Dilute solution characterization of cyclic polystyrene molecules and their zero-shear viscosity in the melt[J]. Macromolecules, 1987, 20(3):498-512. [12] Liu W, Budtova T. Dissolution of unmodified waxy starch in ionic liquid and solution rheological properties[J]. Carbohydrate Polymers, 2013, 93(1):199-206. [13] Pishvaei M, Graillat C, Mckenna T F, et al. Experimental investigation and phenomenological modeling of the viscosity

investigated as part o f studies on toughening of PBT. POs used for the study were ethylene propylene rubber (EPR), low-density polyethylene (LDPE), and high-density polyethylene (HDPE), whose deformabilities were different at room temperature. It was observed that the particle size of PO in the discrete phase was the smallest when the EAG content was 8~12 wL%. Shear viscosity o f the blends increased as the particle size was decreased. It seems that the morphology and rheological properties of the blends were affected by graft copolymers formed in situ from EAG and