scholarly journals The Rheological Properties of Concentrated Suspensions. III. Dynamic Properties and Their Correlations with Stationary Flow Properties

1964 ◽  
Vol 37 (1) ◽  
pp. 78-89 ◽  
Author(s):  
Masaharu Takano

2015 ◽  
Vol 645-646 ◽  
pp. 394-399
Author(s):  
Wei Gao ◽  
Qi Long Wei ◽  
Ling Ding ◽  
Xiao Yuan Li ◽  
Chao Wang ◽  
...  

A multi-scale method was developed, which utilized intrinsic relationships among zeta potential of particles, rheological properties of suspensions and particle size distribution (PSD), to analyze dispersion behavior of nanoparticles in concentrated suspensions. It was found that PSD of a kind of nanoceria particles by dynamic light scattering (DLS) method in solution A with concentration 5 wt% accorded well with that by direct TEM analysis, which meant the particles had been dispersed well. However, there had a significant difference when the concentration was increased to 20 wt%. When particles concentration increased from 5 wt% to 20 wt%, zeta potential in solution A changed from-150 mV to-100 mV, while zeta potential in solution B changed from-35mV to-45 mV. Variations of zeta potential of particles accorded well with rheological properties of suspensions too, from phenomenological models. When the suspensions composed by solution A and the nanoparticles with concentration about 20 wt% was diluted with its original solution to 5 wt%, the PSD of nanoceria could be measured indirectly, which accorded well with both that of a suspension prepared directly with near concentration and that from TEM images. Then a method to measure PSD of nanoparticles in concentrated suspension was brought forward.



1975 ◽  
Vol 29 (2) ◽  
pp. 1008-1014 ◽  
Author(s):  
V. M. Gorislavets ◽  
A. A. Dunets




1992 ◽  
Vol 289 ◽  
Author(s):  
Gebran N. Karam

AbstractThe most important property of cements and concretes after strength is the workability, which is controlled by the rheological characteristics of the mix. Theoretical modeling having proved complicated and in some cases mathematically untractable, cement specialists have concentrated on empirical based models for the last two decades. The major theoretical contributions to date on the properties of colloidal and concentrated suspensions are summarized and a general framework for theoretical modeling of cement viscosity is established. The empirical modeling and the experimental investigation of the rheological properties of fresh cements are reviewed and discussed. A semi-empirical model is proposed and its validity tested in the interpretation of some published experimental results.



2017 ◽  
Vol 35 (No. 5) ◽  
pp. 440-448 ◽  
Author(s):  
Rasouli-Pirouzian Haniyeh ◽  
Peighardoust Seyed Hadi ◽  
Azadmard-Damirchi Sodeif

The effects of sugar substitutes on rheological characteristics of compound milk chocolate using a simplex-lattice mixture design were evaluated. For this purpose, two bulking agents (maltitol and xylitol) at different levels (0–100%) were used and ten formulations were examined in order to find the optimum levels. All chocolate samples showed shear thinning behaviour. It was found that compound milk chocolate behaved as a Casson fluid. Chocolate formulations containing the highest maltitol substitution resulted in similar flow properties compared to those of the control and hence can be a good alternative. The results demonstrated that chocolate combinations containing 87.8% maltitol and 12.2% xylitol were found as the optimum concentrations producing the most acceptable rheological properties.



1979 ◽  
Vol 205 (1160) ◽  
pp. 323-345 ◽  

The flow properties of axoplasm have been studied in a defined chemical environment. Axoplasm extruded from squid giant axons was introduced into porous cellulose acetate tubes of diameter roughly equal to that of the original axon. Passage of axoplasm along the tube rapidly coated the tube walls with a layer of protein. By measuring the rate of flow back and forth along the tube, the rheological properties of the axoplasm plug were investigated at a range of pressures and in a variety of media. Axoplasm behaves as a classical Bingham body the motion of which can be characterized by a yield stress ( θ ) and a plastic viscosity ( η p1 ). In a potassium methanesulphonate medium containing 65 nM free Ca 2+ , θ averaged 109 ± 46 dyn/cm 2 and η p1 146 ± 83 P. † These values were little affected by ATP, colchicine, cytocholasin B or by replacing K by Na but were sensitive to the anion composition of the medium. The effectiveness of different anions at reducing θ and η p1 was in the order SCN > I > Br > Cl > methanesul­phonate. θ and η p1 were also drastically reduced by increasing the ionized Ca. This effect required millimolar amounts of Ca, was unaffected by the presence of ATP and was irreversible. It could be blocked by the protease inhibitor TLCK. E. p. r. measurements showed that within the matrix of the axoplasm gel there is a watery space that is largely unaffected by anions or calcium.



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