## Appl Rheol online available publications for selected issue

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Rikdahl M: The Annual European Rheology Conference (AERC 2010), Appl. Rheol. 20 (2010) 245.Norbert Willenbacher

Rheology of colloidal systems

Appl. Rheol.20:4 (2010) 254-254 ►

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Willenbacher N: Rheology of colloidal systems, Appl. Rheol. 20 (2010) 254.

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Rheological Societies: Society's Site Sep 2010 - Feb 2011, Appl. Rheol. 20 (2010) 252.

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Maldonado-Valderrama J, Martin-Rodriguez A, Galvez-Ruiz MJ, Cabrerizo-Vilchez MA: Food Colloids 2010: On the Road from Interfaces to Consumers, Appl. Rheol. 20 (2010) 243.

An enhanced version of the flexure-based microgap rheometer (FMR) is described which enables rheological measurements in steady state shearing flows of bulk fluid samples of PDMS with an absolute gap separation between the shearing surfaces of 100 nm - 100 μmm. Alignment of the shearing surfaces to a parallelism better then 10_{-7}rad allows us to reliably measure shear stresses at shear rates up to 104 s_{-1}. At low rates and for shearing gaps < 5 mm the stress response is dominated by sliding friction between the surfaces that is independent of the viscosity of the fluid and only determined by the residual particulate phase (dust particles) in the fluid.This behaviour is similar to the boundary lubrication regime in tribology.The absolute gap control of the FMR allows us to systematically investigate the flow behaviour at low degrees of confinement (gap separations 100 nm - 2 μm) that cannot be accessed with conventional (controlled normal load) tribological test protocols.► Cite this publication as follows:

Clasen C, Kavehpour HP, McKinley GH: Bridging Tribology and Microrheology of Thin Films, Appl. Rheol. 20 (2010) 45049.

We present a model for osmotic pressure and shear modulus of highly concentrated emulsions by including the interdroplet interaction in terms of disjoining pressure. The results show that even a small addition in interdroplet interaction can lead to significant deviations from the classical Princen-Lacasse-Mason models that take into account only the surface energy as the sole source of elasticity. The newly proposed model predicts new effects, in particular the possibility of nonlinear dependency of elastic modulus on the droplet size, and can be used to discuss the elasticity sources of highly concentrated emulsions. In the second part of this article, the unusual elasticity of highly concentrated explosive emulsions is discussed by using the proposed model.► Cite this publication as follows:

Foudazi R, Masalova I, Malkin A: Effect of interdroplet interaction on elasticity of highly concentrated emulsions, Appl. Rheol. 20 (2010) 45096.

The yield stress of a magnetorheological fluid was measured as a function of magnetic flux density using different techniques. The yield stress values were determined by extrapolating the experimental shear stress-shear rate data to zero shear rate with the help of Bingham and Herschel-Bulkley models, and by using stress ramp and dynamic oscillatory tests.To obtain the rheological data, the rotational rheometer equipped with a magnetic field generator and a plate-and-plate measuring geometry was used. The different methods produced yield stress values which were in reasonable agreement with each other.► Cite this publication as follows:

Jonkkari I, Syrjala S: Evaluation of techniques for measuring the yield stress of a magnetorheological fluid, Appl. Rheol. 20 (2010) 45875.

A new magnetocell, based on a plate-plate twin gap with housing and integrated online flux density measurement, allows for a reliable rheological characterization of magneto¬rheological fluids (MRF). Various modifications introduced into the commercial magnetocell version MRD180/1T (Physica/Anton Paar), distinctly improve the homogeneity of the magnetic flux density distribution and broaden the range of accessible shear rates in a MCR501 rheometer up to more than 3000 s-1. The new design has been licensed to the manufacturer, to provide a commercial twin gap magnetocell. Fixed volume dosing of MRF yields an improved reproducibility of flow curve measurements, as required for the design of technical devices like MR clutches and MR brakes. The twin gap magnetocell enables the mimicking of MRF response relevant for clutch and brake applications, like shear rate or shear stress step or ramp testing, and drive cycle testing.The dynamic shear stress response to changes of flux density and/or shear rate may be characterized. Testing of MRF is possible for brake applications under constant holding torque conditions in the pre-yield regime. MRF creep and recovery for various imposed shear stresses may be monitored as a function of time. Comparison with a concentric cylinder pilot clutch underlines the validity of the shear stress versus flux density characteristic as determined with the twin-gap magnetocell.► Cite this publication as follows:

Gabriel C, Kieburg C, Laun HM: Clutch and brake related testing of magnetorheological fluids using the BASF twin gap magnetocell, Appl. Rheol. 20 (2010) 41778.

This article reports viscosity data on a series of colloidal dispersions collected as part of the International Nanofluid Property Benchmark Exercise (INPBE). Data are reported for seven different fluids that include dispersions of metal-oxide nanoparticles in water, and in synthetic oil. These fluids, which are also referred to as 'nanofluids,' are currently being researched for their potential to function as heat transfer fluids. In a recently published paper from the INPBE study, thermal conductivity data from more than 30 laboratories around the world were reported and analyzed. Here, we examine the influence of particle shape and concentration on the viscosity of these same nanofluids and compare data to predictions from classical theories on suspension rheology.► Cite this publication as follows:

Venerus DC, Buongiorno J, Christianson R, Townsend J, Bang I, Chen G, Chung S, Chyu M, Chen H, Ding Y, Dubois F, Dzido G, Funfschilling D, Galand Q, Gao J, Hong H, Horton M, Hu L-W, Iorio CS, Jarzebski AB, Jiang Y, Kabelac S, Kedzierski MA, Kim C, Kim J-H, Kim S, McKrell T, Ni R, Philip J, Prabhat N, Song P, VanVaerenbergh S, Wen D, Witharana S, Zhao X-Z, Zhou S-Q: Viscosity measurements on colloidal dispersions (nanofluids) for heat transfer applications, Appl. Rheol. 20 (2010) 44582.

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