Two new ERC grantees will use the ESRF extensively for geosciences and biomineralisation studies

TILMAN GRÜNEWALD - TexTOM

“EBS is just what I need right now for my research. It feels as if someone had lifted the curtain and set the stage for a whole new kind of experiments”, explains Tilman Grünewald, researcher at the Institut Fresnel (Aix-Marseille Univ/CNRS/Centrale Marseille) and former post-doc at ID13. With his grant, he will carry out experiments at the ESRF to understand the structural make-up of the enthesis, the biological connection between tendon and bone, which is often involved in orthopedic injuries.

Hierarchical structures are present in many biological materials such as enthesis and one key feature is that their mesoscopic organization and crystallographic texture is important for their mechanical properties. Resolving the local structure and texture spatially while keeping a large field of view is an unsolved problem. Grünewald will tackle this by introducing texture tomography, a new 3D x-ray diffraction imaging method with support from ID13 and ID15A. He will carry out texture tomography experiments and perform micromechanical modelling. Both techniques together will enable him and his collaborators at the Institut des Sciences du Mouvement to couple the hierarchical structure with the mechanical behaviour of the enthesis.

His previous post-doctoral experience at the ESRF proved very useful in the process of applying for the ERC grant. “My post-doc time at the ESRF was an opportunity for me to build a network, develop new ideas and offered me an astonishing set of tools to do my research”, says Grünewald. “I came to the ESRF with lots of ideas and I had the chance to explore them thanks to the complementarity of different beamlines, and this knowledge has been crucial for the development of my project and ultimately, the success of my application”.

ILYA KUPENKO - LECOR

“My project aims to combine high-pressure high-temperature experiments with various synchrotron techniques, with the aim of solving the question of the composition of the Earth’s core”, explains Ilya Kupenko, researcher at the University of Münster (Germany) and former post-doctoral researcher on ID18.

Since the discovery of the Earth’s internal structure and the existence of a dense metallic core about a century ago, the idea of iron being the dominant component of the core gained firm support confirmed by cosmochemical and geochemical observations, seismic data, the theory of geomagnetism, and high-pressure studies. However, there is strong evidence that around 3-7 wt% of light elements should be present in the inner core and hydrogen, carbon, oxygen, silicon, and sulphur are the most plausible candidates. Data on the physical properties of some candidate materials at simultaneous high pressures and temperatures that are relevant to the Earth core are almost absent.

Kupenko will study the sound velocities and plastic deformation mechanisms of candidate iron alloys and compounds in situ at extreme pressure-temperature conditions using a combination of state-of-the-art synchrotron X-ray techniques almost exclusively at the ESRF.

He will use ID14, the new beamline replacing the old nuclear resonant scattering beamline ID18 by 2024. Kupenko will be involved in the construction of the beamline. “I need a really small beam with high flux and ID14 will provide me with exactly that”, he says. He will use  ID14 and ID28 for sound velocities experiments, and ID27 together with ID15B to study the anisotropy of the Earth’s core (the fact that velocities in the core are faster in the polar direction than in the equatorial plane) and for other diffraction experiments.

Kupenko is no newcomer to the ESRF: he was based at the ESRF for part of his PhD and completed a post-doctoral fellowship at ID18. “My experience at the ESRF taught me how to organise experiments, how to prepare the samples and other processes that are ‘behind the scenes’ but that really helped me to structure and define the ERC project”, he says.

Text by Montserrat Capellas Espuny.

Top image: Tilman Grünewald (left) and Ilya Kupenko (right).