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Thermodiffusion, which leads to a component separation in a mixture due to the thermal gradient, still does not have an unambiguous microscopic picture. Therefore, experimental studies, especially in convection free environment, are important. As part of the 4th campaign on the DCMIX project, thermodiffusion experiments on three compositions of the toluene-methanol-cyclohexane ternary mixture, on a mixture of fullerene-tetralin-toluene and on a mixture of polystyrene-toluene-cyclohexane have been performed in microgravity conditions on board the International Space Station. A binary mixture of polystyrene-toluene has been filled into the companion cell for the campaign. The Selectable Optical Diagnostics Instrument (SODI), wich is a two-wavelength Mach-Zehnder interferometer for the ternary mixtures, plus a monochromatic Mach-Zehnder interferometer for the binary mixture, has been used in order to obtain the temperature and the concentration fields in the cells. Precisely, it is a 5-steps phase-shifting interferometry technique which is implemented with SODI, producing by means of laser illumination a set of 5 phase-shifted images of π/2 between them as function of the time. A total of 58 runs of various durations and at different mean temperatures have been conducted. Here, we evaluate the contrast of the interferograms, the quality in the phase stepping, the stability of the thermal regulation of the experiments and the level of environmental disturbances on board the space station during the campaign., SCOPUS: ar.j, info:eu-repo/semantics/published

International audience; Superconductor/Ferromagnet (S/F) hybrid systems show interesting magneto-transport behaviors that result from the transfer of properties between both constituents. For instance, magnetic memory can be transferred from the F into the S through the pinning of superconducting vortices by the ferromagnetic textures. The ability to tailor this type of induced behavior is important to broaden its range of application. Here we show that engineering the F magnetization reversal allows tuning the strength of the vortex pinning (and memory) effects, as well as the field range in which they appear. This is done by using magnetic multilayers in which Co thin films are combined with different heavy metals (Ru, Ir, Pt). By choosing the materials, thicknesses, and stacking order of the layers, we can design the characteristic domain size and morphology, from out-of-plane magnetized stripe domains to much smaller magnetic skyrmions. These changes strongly affect the magneto-transport properties. The underlying mechanisms are identified by comparing the experimental results to a magnetic pinning model. * javier.villegas@cnrs-thales.fr 2

This paper describes the European Space Agency (ESA) experiments devoted to study thermodiffusion of fluid mixtures in microgravity environment, where sedimentation and convection do not affect the mass flow induced by the Soret effect. First, the experiments performed on binary mixtures in the IVIDIL and GRADFLEX experiments are described. Then, further experiments on ternary mixtures and complex fluids performed in DCMIX and planned to be performed in the context of the NEUF-DIX project are presented. Finally, multi-component mixtures studied in the SCCO project are detailed. Graphical abstract: [Figure not available: see fulltext.]., 0, SCOPUS: re.j, info:eu-repo/semantics/published

We report on thermodiffusion experiments conducted on the International Space Station ISS during fall 2016. These experiments are part of the DCMIX (Diffusion and thermodiffusion Coefficients Measurements in ternary Mixtures) project, which aims at establishing a reliable data base of non-isothermal transport coefficients for selected ternary liquid mixtures. The third campaign, DCMIX3, focuses on aqueous systems with water/ethanol/triethylene glycol as an example, where sign changes of the Soret coefficient have already been reported for certain binary subsystems. Investigations have been carried out with the SODI (Selectable Optical Diagnostics Instrument) instrument, a Mach-Zehnder interferometer set up inside the Microgravity Science Glovebox in the Destiny Module of the ISS. Concentration changes within the liquids have been monitored in response to an external temperature gradient using phase-stepping interferometry. The complete data set has been made available in spring 2017. Due to additionally available measurement time, it was possible to collect a complete data set at 30∘C and an almost complete data set at 25∘C, which significantly exceeds the originally envisaged measurements at a single temperature only. All samples could be measured successfully. The SODI instrument and the DCMIX experiments have proven reliable and robust, allowing to extract meaningful data even in case of unforeseen laser instabilities. First assessments of the data quality have revealed six out of 31 runs with some problems in image contrast and/or phase step stability that will require more sophisticated algorithms. This publication documents all relevant parameters of the conducted experiments and also events that might have an influence on the final results. The compiled information is intended to serve as a starting point for all following data evaluations.

International audience; It was designed and constructed a new thermogravitational column able to operate at high pressures (up to 50 MPa). This new thermogravitational column is of the cylindrical type with closed ends. It is made of stainless steel. The length of the column is 0.5 m and the gap between its two walls is variable. First, the column was validated at atmospheric pressure by means of measurements of the thermodiffusion coefficient of well-known binary mixtures. Then, this new thermogravitational column was used to measure the thermodiffusion coefficient of the binary mixtures 1,2,3,4-tetrahydronaphtaleneisobutylbenzene, 1,2,3,4-tetrahydronaphtalenen-dodecane, and isobutylbenzenen-dodecane at high pressures and within the pressure range between 0.1 and 20 MPa at a mean temperature of 25 °C. We have found a linear dependence between the thermodiffusion coefficient and the pressure.