Related papers: Simultaneous rheo-electric measurements of strongl…
The ability to manipulate rheological and electrical properties of colloidal carbon black gels makes them attractive in composites for energy applications such as batteries and fuel cells, where they conduct electricity and prevent…
The rheological characterisation of complex fluids is mostly performed under simple shear flow in rotational rheometers. Their modern commercial versions are extremely sensitive instruments which are able to provide very accurate…
We propose a novel method for measuring linear and non-linear viscoelastic properties of a liquid by the oscillatory motion of an immersed rotating body in a vessel. The shape of a rotating object is general and we tested four different…
Colloidal gels made of carbon black particles dispersed in light mineral oil are "rheo-acoustic" materials, i.e., their mechanical and structural properties can be tuned using high-power ultrasound, sound waves with submicron amplitude and…
Several surfactant molecules self-assemble in solution to form long, flexible wormlike micelles which get entangled with each other, leading to viscoelastic gel phases. We discuss our recent work on the rheology of such a gel formed in the…
We propose a novel device capable of measuring the relaxation time of viscoelastic fluids as small as 1\,ms. In contrast to most rheometers, which by their very nature are concerned with producing viscometric or nearly-viscometric flows,…
We introduce a model gel system in which colloidal forces, structure, and rheology are measured by balancing the requirements of rheological and microscopy techniques with those of optical tweezers. Sterically stabilized poly(methyl…
A wide range of thermoreversible gels are prepared by cooling down to ambient temperature hot aqueous polymer solutions. During the sol-gel transition, such materials may experience a volume contraction which is traditionally overlooked as…
To investigate the interplay between microscopic dynamics and macroscopic rheology in soft matter, we couple a stress-controlled-rheometer equipped with a Couette cell to a light scattering setup in the imaging geometry, which allows us to…
We present a detailed comparison of the rheological behaviour of sheared sediment beds in a pressure-driven, straight channel configuration based on data that was generated by means of fully coupled, grain-resolved direct numerical…
We report contactless measurements of the viscoelastic rheological properties of soft gels. The experiments are performed using a colloidal-probe Atomic Force Microscope (AFM) in a liquid environment and in dynamic mode. The mechanical…
We present here a novel cantilever based apparatus to perform translational stress or strain controlled rheology in very soft solids, and obtain simultaneous confocal imaging of the 3 dimensional microstructure. The stress is measured using…
We present ShearView, a compact, cost-effective, and open-source rheometer that enables both strain- and stress-controlled oscillatory shear experiments, while being fully compatible with high-resolution optical microscopy. Designed for…
A transition from solid-like to liquid-like behavior occurs when colloidal gels are subjected to a prolonged exposure to a steady shear. This phenomenon, which is characterized by a yielding point, is found to be strongly dependent on the…
Hypothesis: While the mechanical disruption of microscopic structures in complex fluids by large shear flows has been studied extensively, the effects of applied strains on the dielectric properties of macromolecular aggregates has received…
Shear cell simulations and experiments of weakly wetted particles (a few volume percent liquid binders) are compared, with the goal to understand their flow rheology. Application examples are cores for metal casting by core shooting made of…
Fluidized granular media have a rich rheology: measuring shear stress $\sigma$ as a function of shear rate $\dot\gamma$, they exhibit Newtonian behavior $\sigma\sim\dot\gamma$ for low densities and shear rates, develop a yield stress for…
An adhesively stressed thin film of a soft hydrogel confined between two rigid flat substrates auto-roughens with its dominant wavelength exhibiting pronounced dependence on the film thickness (H). A linear stability analysis confirmed that…
In this work, we investigate the transient rheological behavior of two soft glassy materials: a clay dispersion and a silica gel, emphasizing their unconventional shear stress build-up behavior under conditions of constant imposed strain.…
The viscoelastic behavior of liquid polymers changes depending on the microstructure of the polymer chains. To investigate the unsteady structural changes induced by polymer chain morphology under stress, we develop a simple rheo-optical…