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Papers by Jacques Persello

HAL (Le Centre pour la Communication Scientifique Directe), Jun 5, 2013

Soumission d'un résumé en vue d'une communication orale portant sur: Propriétés électrorhéologiqu... more Soumission d'un résumé en vue d'une communication orale portant sur: Propriétés électrorhéologiques et applications d'un matériau à base de nanoparticules de dioxyde de titane

HAL (Le Centre pour la Communication Scientifique Directe), Sep 6, 2009

HAL (Le Centre pour la Communication Scientifique Directe), Aug 26, 2013

This study focuses on the superplasticizers which allow to increase the concentration of the part... more This study focuses on the superplasticizers which allow to increase the concentration of the particles (cement) of a concrete while maintaining good handling. The superplasticizerss analyzed here are polyelectrolytic: polymethacrylates grafted with side polyethyleneoxide chains (PEO) of different lengths. We present a study of these molecules in solution, including the influence of OHions on the PEO chains. We analyse the effect of the superplasticizers on the rheology of suspensions of CaCO3 particles of micron and nanometer size ranges..

Journal of environmental chemical engineering, Sep 1, 2013

Two medicinal species of amaranth, Amaranthus viridis L. and A. caudatus L. were evaluated for th... more Two medicinal species of amaranth, Amaranthus viridis L. and A. caudatus L. were evaluated for their ability to uptake heavy metals from a contaminated soil. Twenty healthy plants of each species were transplanted to plastic pots containing the soil contaminated with elevated concentrations of Cd, Cr, Cu, Ni, Pb, and Zn. The plants were harvested after 45 days. Below-and above-ground tissues (roots and shoots) were analyzed separately to determine metals concentrations. Compared with the control group, the effects of S,S-ethylenediaminedisuccinic acid (S,S-EDDS) on the uptake of Cd, Cr, Cu, Ni, Pb, and Zn by two medicinal plants were also investigated. The initial contaminant concentrations of Cd, Cr, Cu, Ni, Pb, and Zn in soil were 2.34, 30.53, 16.14, 20.99, 35.77, and 102.31 mg/kg, respectively. The results of metal accumulation with EDDS application showed that EDDS was more efficient at solubilizing Cu and Zn than the control group. Translocation of metals from roots to shoots was most pronounced for Cu and Zn. The only metal that did not result in a transfer factor (TF) !0.3 for at least one of the two test species was Pb. The enrichment factor (E) was also low for Pb. The lower TF and E for Pb illustrated the tendency of that metal to remain bound to soil particles and not transfer into plant tissues. These data suggest that these two medicinal species of Amaranthus could be hyperaccumulators of several of these metals, and were particularly effective in accumulating Zn and Cu. Pb and Cd, while accumulated in measurable amounts, did not decrease significantly in the soil, suggesting these species may not be the best choice for plants to be used when bioremediating Pb-or Cd-contaminated areas.

HAL (Le Centre pour la Communication Scientifique Directe), Sep 8, 2016

Matériaux & Techniques, 2002

Magnetorheological fluids are made of magnetic particles dispersed in some carrier fluid. Their r... more Magnetorheological fluids are made of magnetic particles dispersed in some carrier fluid. Their rheology can be strongly modified by the application of a magnetic field. In a similar way, a magnetic elastomer is obtained by mixing these magnetic particles inside some polymer before curing. If, before curing, the particles have been aligned with the help of a magnetic field, then the viscoelatic properties of the material can be changed to a large extent in the presence of a magnetic field. A third type of material can be realized with the same particles by taking a liquid crystal for the matrix. In these three cases these are the magnetic interactions that allow controlling the response of the material. We present some results obtained with the magnetic elastomers together with an interpretation based on a calculation of forces between the particles. We show that the magnetostriction remains very low in elastomer whereas it could reach 20 % in nematic elastomers containing iron particle

Un fluide electrorheologique compose de particules de dioxide de titane dopees avec de l'acet... more Un fluide electrorheologique compose de particules de dioxide de titane dopees avec de l'acetylacetone 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. a une frequence de 10Hz. A plus haute frequence le module diminue sensiblement. L'analyse de la permiittivite et de la conductivite de cette suspension en fonction de la frequence permet d'expliquer ce comportement. On comparera les valeurs de module obtenues avec ce fluide electrorheologique a celles qui peuvent etre obtenues avec un fluide magnetorheologique. On presentera plus particulierement les applications potentielles de ce type de materiau pour des transducteurs electromecaniques dans le cas ou le fluide a base d'huile silicone a ete polymerise pour former un elastomere electrorheologique.

HAL (Le Centre pour la Communication Scientifique Directe), Sep 4, 2016

Industrial & Engineering Chemistry Product Research and Development, 1983

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The Journal of Physical Chemistry B, 2004

... Jacques Persello, Jean-Philippe Boisvert,* Aurélien Guyard, and Bernard Cabane §. ... T... more ... Jacques Persello, Jean-Philippe Boisvert,* Aurélien Guyard, and Bernard Cabane §. ... The experimental curves were modeled within the Percus−Yevick (PY) model where monodisperse hard-sphere particles are assumed to have a liquidlike distribution. ...

Surface and Coatings Technology, 2005

This paper presents a new silica-based coating procedure for the protection of electrogalvanized ... more This paper presents a new silica-based coating procedure for the protection of electrogalvanized steel against corrosion. Besides corrosion resistance properties, one of the main objectives of the study was to evaluate the viability of a simple and industrially easy-to-implement ...

Pure and Applied Chemistry, 2005

Solid-liquid separation is an operation that starts with a dispersion of solid particles in a liq... more Solid-liquid separation is an operation that starts with a dispersion of solid particles in a liquid and removes some of the liquid from the particles, producing a concentrated solid paste and a clean liquid phase. It is similar to thermodynamic processes where pressure is applied to a system in order to reduce its volume. In dispersions, the resistance to this osmotic compression depends on interactions between the dispersed particles.The first part of this work deals with dispersions of repelling particles, which are either silica nanoparticles or synthetic clay platelets, dispersed in aqueous solutions. In these conditions, each particle is surrounded by an ionic layer, which repels other ionic layers. This results in a structure with strong short-range order. At high particle volume fractions, the overlap of ionic layers generates large osmotic pressures; these pressures may be calculated, through the cell model, as the cost of reducing the volume of each cell. The variation of ...

Polymer International, 2003

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