CoCogel-DC5-PhD position opening: Tuning colloidal gels with ultrasound

CoCogel-DC5 : Tuning colloidal gels with ultrasound

PhD position opening

Advisor: Thomas Gibaud (CNRS, École Normale Supérieure de Lyon)

Co-advisors: Valeria Garbin (TU Delft) & Fabrice Toussaint (Holcim)

Context – High-power ultrasound has long been known to disrupt particulate aggregates with applications to resuspension, filtration and cleaning, optimization of food products, and drug delivery. However, the underlying physical mechanisms remained unclear. Recently, we quantified the impact of high-power ultrasound on model colloidal gels, revealing substantial softening under ultrasonic vibrations associated with the nucleation of micron-sized cracks within the gel network. see: T. Gibaud et al., Physical Review X 10, 011028 (2020).

PhD project – Within “CoCoGel” (https://cocogel.iesl.forth.gr/), a Marie Skłodowska-Curie Industrial Doctoral Network (HORIZON-MSCA-2022-DN-01-01), a PhD position is available at École Normale Supérieure de Lyon in collaboration with the university TU Delft, the building materials company Holcim and the food company Unilevers.

The PhD candidate will investigate the properties of “rheo-acoustic” gels, i.e., colloidal gels that are mechanically responsive to ultrasound. Experiments will consist in tracking the system response to ultrasound through structural characterization (microscopy and light or X-ray scattering) and mechanical measurements (rheology and microrheology).

The PhD candidate will also explore some applications of the above concepts to industrial systems. In particular, the PhD candidate will spend 15 months at the Holcim Innovation Center (Saint-Quentin-Fallavier, Fr) to use high-power ultrasound in order to control and tune the flow properties of cement pastes, a major current issue to reduce the carbon footprint of concretes. The PhD candidate will also explore application in Food science for 3 mounts at Unilever’s global Foods Innovation Centre (Wageningen, NL)

Skills – We are looking for a candidate holding a master in soft matter science with a general background in physics, physical chemistry, or material sciences. Prior knowledge of rheology, microscopy, and image analysis (ImageJ, Matlab, or Python) will be a good asset. Additional experience in scattering will be appreciated.

Dates & remuneration – 3 years starting as soon as possible. Gross salary: 3000–3500€ per month.

Contact – Applications must be submitted through https://emploi.cnrs.fr to be considered and include a resume and a motivation letter. Please contact thomas.gibaud@ens-lyon.fr for more information.

• https://emploi.cnrs.fr/Offres/Doctorant/UMR5672-THOGIB-006/Default.aspx…

To qualify for the positions, the applicant cannot have resided or carried out his/her main activity (work, studies, etc.) in the France for more than 12 months in the 36 months preceding the recruitment start date.