Jean Colombani

"La profondeur se cache à la surface des choses." Friedrich Nietzsche

• [February 2024] 25 years ago, during my PhD thesis, we had shown that the Soret coefficient of aqueous LiCl shows a minimum with concentration and changes sign with temperature. Colleagues from the Jülich Forschungszentrum have obtained similar results with another experimental method, and propose a convincing interpretation of this odd behavior. 
  

• [June 2023] We had verified experimentally in 2017 for the first time the existence of the minimum of yield strain of colloidal gels with concentration, predicted 25 years before by the standard model of colloidal gels (fractal elasticity model). In a study on human cell morphogenesis, scientists have also observed recently this minimum in polyurethane-based gels.
  

• [January 2023] I am currently spending two weeks in Niteroi, close to Rio de Janeiro, visiting my colleague Fabio Reis from the Universidade Federale Fluminense, thanks to one of his grant from the Capes Brazilian funding agency. This is really an amazing stay.

• [December 2022] A third Arqus grant! This time, a colleague from the University of Granada will come during one month in Lyon to carry out particle image velocimetry measurements.

• [October 2022] It's been 10 years since I published a paper in collaboration with a private company. I am glad to present our recent work, from a collaboration with colleagues from the University of Grenoble and the Arjowiggins company, about the recycling of printed paper electronics.

• [September 2022] Two new articles have just been released on the PhD thesis of Alexandra Mailleur on the evaporation of water drops on salt substrates: one about the flows inside the drop, another one about the hollow structures obtained after drying.

• [March 2022] We've been granted a second Arqus funding! This time, a colleague from Padua will come to Lyon during one month to perform holographic interferometry experiments.

• [February 2021] In the context of an artistic residence in the lab, I have started a science-art collaboration with Francis. Fascinating experience! First image.

• [December 2020] The current background is strange, and has slowdonwed the activity. But I was lately granted an Arqus funding to spend one sabbatical month in Padua (Italy). I look forward!

• [May 2019] A popularization article about my recent stay at the faculty of technical sciences of the University of Novi Sad, in Serbia, has just been published.
  

• [November 2018] A first article on the PhD thesis of Alexandra Mailleur is now published, and it is in cover of Physical Review Letters! It shows how a simple water drop evaporating on a salt single crystal produces surprising hollow structures.

• [December 2017] For the first time, with a colleague, we have published a comment, about a possible mechanism of calcium carbonate rock degradation. This is a quite delicate to criticize publicly the work of other researchers.

• [May 2017] We had shown in 2011, with indirect measurements, that the moist creep of gypsum plaster was driven by a dissolution-precipitation process. Recent experiments have confirmed this statement.

• [March 2017] 20 years ago, during my PhD thesis, we had shown that the Soret coefficient of aqueous LiCl shows a minimum with concentration and changes sign with temperature. These measurements have just been verified in molecular simulations and computationally modeled. Never say die!

• [February 2017] We had shown, with order of magnitude considerations, that a dissolution-precipitation process may contribute to the humid creep of concrete. A team from UCLA has recently validated experimentally this assumption, further confirmed by experiments in Tokyo.

• [February 2017] We have verified experimentally for the first time the existence of the minimum of yield strain of colloidal gels with concentration, predicted 25 years ago by the standard model of colloidal gels (fractal elasticity model).

• [September 2016] We have just published the first measurement of the reaction rate of the attack of Portland cement by several strong acids.

• [July 2016] We have recently published a critical review of the experimental measurements of the dissolution rate of calcite.

• [June 2016] A popularization article has been published about our research on droplet evaporation in microgravity. Look at the funny video inside.