PERSELLO , Jacques

Recently, electro-active composites have been considered by several researchers because they exhibit an interesting change in their viscoelastic properties under an applied electric field. However, their relative elastic modulus change ΔG'=G'(E)-G'(0) is still low and rarely exceed 100 kPa. In this article, we demonstrated that, by synthesizing...

We present experimental results on electrorheological behavior under an ac electric field, and dielectric properties of colloidal suspensions composed of aggregated titanium dioxide nanoparticles dispersed in insulating PDMS silicon oil, as a function of adsorbed acetylacetone (Acac) dipolar molecules on TiO2 surface. The results show that the...

We present experimental results on electrorheological behavior under an ac electric field, and dielectric properties of colloidal suspensions composed of aggregated titanium dioxide nanoparticles dispersed in insulating PDMS silicon oil, as a function of adsorbed acetylacetone (Acac) dipolar molecules on TiO2 surface. The results show that the...

International audience

International audience

International audience

International audience

We present a comparison of experimentally and theoretically determined osmotic pressures for various colloidal dispersions. Experimental data is collected from several different silica and polystyrene dispersions. The theoretical pressure determinations are based on the Primitive Model combined with the Cell Model and the physical quantities...

Un fluide électrorhéologique composé de particules de dioxide de titane dopées avec de l'acétylacétone en suspension dans une huile silicone, montre un acrroissement de module de cisaillement de 1.8MPa par application d'un champ de seulement 1KV/mm. à une fréquence de 10Hz. A plus haute fréquence le module diminue sensiblement. L'analyse de...

Les fluidifiants utilisés dans l'industrie cimentaire permettent d'augmenter la fraction volumique en particules de la suspension afin d'accroître les propriétés mécaniques du béton tout en conservant une maniabilité satisfaisante lors de sa mise en œuvre. Notre étude est centrée sur le mode d'action du fluidifiant. Dans ce but nous étudions la...

Nanocomposite materials present attractive properties and are widely employed in various applications. Most of the time, the insertion of nanoparticles in a polymer matrix induces an enhancement of its performances, yet the effect of the filler on the polymerization mechanisms and the glass transition is less often investigated. In the present...

In this work, the rheological properties of suspensions of micron-sized gypsum particles dispersed in water were studied in the presence of different fluidizer molecules. The yield stress and the shear moduli were measured versus the volume fraction in the presence of these molecules. Using the same polyelectrolyte with different molecular...

In this work, the rheological properties of suspensions of micron-sized gypsum particles dispersed in water were studied in the presence of different fluidizer molecules. The yield stress and the shear moduli were measured versus the volume fraction in the presence of these molecules. Using the same polyelectrolyte with different molecular...

Cu2ZnSnS4 (CZTS) shows great potential for photovoltaic application because of its non-toxic earth-abundant components and good optoelectronic properties. Combining low-cost and environmentally friendly routes would be the most favorable approach for the development of CZTS solar cells. In this context, development of Cu2ZnSnS4 (CZTS) films...

In this work, iron oxide magnetic nanoparticles (MNP) were synthesized, whose surface was recovered with an oleate double layer in order to investigate the ability of this material to adsorb nickel ions. First, the solution chemistry of oleate ions was investigated in order to determine the CMC value and the arrangements of ions above the CMC....

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