Adsorption of Zr,Hf, Nb,Ta and Pa on macroporous anion exchangers in HF medium

The behaviour of the elements Zr, Hf, Nb, Ta and Pa has been investigated on macroporous anion exchange resin BIORAD AGMP 1 in HF medium (from 0.02 to 2M). All the studied elements show strong adsorption properties at low HF concentration. The adsorption was found to be highly dependent on H⁺ and F^– concentrations. The distribution of possible adsorbable complexes is discussed.     

Asymptotic analysis of a transport model of organic material through a stratified porous medium: Concentration effect

We consider the transport through capillarity of an organic material inside a porous medium, using Leverett’s model. We first prove an existence result for a weak solution of this nonlinear evolution problem, using a regularization process. We then describe the asymptotic behavior of the solution, when the permeability _kε$k_{\epsilon }$ of the porous medium is associated to a scalar function which only depends on the third variable, assuming that _kε$k_{\epsilon }$ (resp. the inverse of _kε$k_{\epsilon }$) converges to some measure _λ∗${\lambda }_{\ast }$ (resp. λ^∗${\lambda }^{\ast }$). We use Γ-convergence arguments in order to describe this asymptotic behavior. We finally characterize the asymptotic behavior of the problem, considering special choices of the permeability _kε$k_{\epsilon }$, which correspond to stratified porous media, and give a numerical test for a 1D model.     

Sur l'interpolation des opérateurs maximaux monotones

On the Interpolation of Maximal Monotone Operators. We study here one way to extend to the maximal monotone case the results of linear interpolation, exposed bybalakrishnan in [2]. We obtain a necessary and sufficient condition of convergence for sequences(A ⁿ ) _n of maximal monotone operators on a real Hilbert spaceH.     

On the interface boundary conditions between two interacting incompressible viscous fluid flows

We consider two incompressible viscous fluid flows interacting through thin non-Newtonian boundary layers of higher Reynolds? number. We study the asymptotic behaviour of the problem, with respect to the vanishing thickness of the layers, using Γ-convergence methods. We derive general interfacial boundary conditions between the two fluid flows. These boundary conditions are specified for some particular cases including periodic or fractal structures of layers.     

New7Be(p, γ)8B cross section measurement

The⁷Be(p,γ)⁸B cross section has been re-measured using radioactive targets. The zero-energy astrophysical S-factor is found significantly lower than the previously adopted value.     

Non-isothermal oxidation and kinetic analysis of pure magnesium powder

Journal of Thermal Analysis and Calorimetry - With high energy densities, metals appear as innovative energy carriers. In the present study, magnesium powder is considered as fuel for energy...     

Evidence for the radioactive decay of Ra by C emission

Using a magnetic spectrometer and an intense ²²⁶Ra source, first evidence for the radioactive decay of ²²⁶Ra by ¹⁴C emission was obtained leading to a measured branching ratio relative to -particles of (3.2±1.6)×10⁻¹¹. In addition, the decay of ²²²Ra by ¹⁴C emission, previously reported, was clearly observed and an upper limit was set for the emission of ³⁴Si from ²⁴¹Am.     

Relaxed Dirichlet problem and shape optimization within the linear elasticity framework

This work is mainly motivated by the study of shape optimization problems within the linear elastic framework and posed in general variable subdomains of a domain of or 3. We precisely study the sets of measures which can be obtained through the relaxed optimization process. The case of an homogeneous and isotropic elastic material is specially emphasized.