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Structural and physical consequences of downsizing to form nanopowders or nanoceramics are very important both from applicative and fundamental point of view. We will discuss, using ab‐initio‐based calculation and Landau theory the origins and the consequences on structural properties when synthesizing nano‐objects with BaTiO3 and SrTiO3 , and show how to use nanostructuration to optimize properties such as electrocaloric effects or energy storage. For instance calculations in BaTiO3 show the possibility to form new phases (fig.1) in which vortices of polarization compete with homogeneous polarization or in which (in nanotorus) homogeneous hypertoroidization of nanotori coexists with axialhomogeneous toroidization. In SrTiO3 a new low temperature ground state, evidenced by synchrotron and neutron diffraction is discussed within the Landau theory and compared with the situation in thin films and during pressure experiments. The crucial competition between particles shape anisotropy, surface tension and shear strain is analyzed. Inducing a specific core‐shell structure is therefore a new and easy way to tailor structural properties and to stabilize new phases that cannot exist in bulk material, just like film deposition on substrate.

We present accurate measurement of the VV- and VH-polarized Raman spectra of vitreous SiO2 pressurized in the range 0 – 8 GPa in argon or helium atmosphere by means of diamond anvil cell. A fine quantitative analysis of the behavior of the Raman modes in function of pressure is achieved with the help of an old central-force model by Sen and Thorpe describing the dynamics of covalently bonded networks. The model predicts the effect of changes in force constants and bond angles on the vibrational frequencies of the coupled SiO4 tetrahedral network. We show that the pressure shift of the Raman bands cannot be understood without encompassing the variations of both parameters. Investigating two different pressurizing fluids including He which is adsorbed into the silica network, allows revealing the role of each parameter in the compression mechanism of the glass.

We report the measurement of non-equilibrium interfacial tension of polymer and hard sphere suspensions in contact with their own solvent. By visualizing fingering instability (VF) in radial Hele-Shaw geometry, we measure interfacial tension in function of the volume fraction of the suspensions showing that the internal degrees of freedom of the particles drive the magnitude of such tension. We rationalize our findings proposing a phenomenological model capturing the compositional dependence of the non equilibrium interfacial tension for the whole range of concentration gradients and for all the systems at hand. More generally we propose the analysis of fluid dynamic instabilities as a new tool to measure interfacial tensions between complex fluids.

An holographic microscopy setup using two illumination beams is proposed to image blood microcirculation in preclinical models. Greedy algorithm reconstruction of the two resulting holograms leads to a 3D reconstruction of the sample over time.

A holographic microscopy algorithm is proposed enabling to deal with high numerical aperture holograms. Hologram reconstruction kernel performs under afocal conditions , which allows keeping the full NA over wide defocus range.