References of "Legros, Jean-Claude"
     in
Bookmark and Share    
Full Text
Peer Reviewed
See detailCounterdiffusion protein crystallisation in microgravity and its observation with PromISS (Protein Microscope for the International Space Station)
Zegers, Ingrid; Carotenuto, Luigi; Evrard, Christine ULg et al

in Microgravity Science and Technology (2006), XVIII

The crystallisation by counterdiffusion is a very efficient technique for obtaining high-quality protein crystals. A prerequisite for the use of counterdiffusion techniques is that mass transport must be ... [more ▼]

The crystallisation by counterdiffusion is a very efficient technique for obtaining high-quality protein crystals. A prerequisite for the use of counterdiffusion techniques is that mass transport must be controlled by diffusion alone. Sedimentation and convection can be avoided by either working in gelled systems, working in systems of small dimensions, or in the absence of gravity. We present the results from experiments performed on the ISS using the Protein Microscope for the International Space Station (PromISS), using digital holography to visualise crystal growth processes. We extensively characterised three model proteins for these experiments (cablys3*lysozyme, triose phosphate isomerase, and parvalbumin) and used these to assess the ISS as an environment for crystallisation by counterdiffusion. The possibility to visualise growth and movement of crystals in different types of experiments (capillary counterdiffusion and batch-type) is important, as movement of crystals is clearly not negligible. [less ▲]

Detailed reference viewed: 53 (9 ULg)
Peer Reviewed
See detailConvection and interfacial mass exchange
Colinet, P.; Legros, Jean-Claude; Dauby, Pierre ULg et al

in ESA Special Publication (2005, October 01)

Mass-exchange through fluid interfaces is ubiquitous in many natural and industrial processes. Yet even basic phase-change processes such as evaporation of a pure liquid are not fully understood, in ... [more ▼]

Mass-exchange through fluid interfaces is ubiquitous in many natural and industrial processes. Yet even basic phase-change processes such as evaporation of a pure liquid are not fully understood, in particular when coupled with fluid motions in the vicinity of the phase-change interface, or with microscopic physical phenomena in the vicinity of a triple line (where the interface meets a solid). Nowadays, many industries recognise that this lack of fundamental knowledge is hindering the optimisation of existing processes. Their modelling tools are too dependent on empirical correlations with a limited - and often unknown - range of applicability. In addition to the intrinsic multiscale nature of the phenomena involved in typical industrial processes linked to interfacial mass exchange, their study is highly multi-disciplinary, involving tools and techniques belonging to physical chemistry, chemical engineering, fluid dynamics, non-linear physics, non-equilibrium thermodynamics, chemistry and statistical physics. From the experimental point of view, microgravity offers a unique environment to obtain valuable data on phase-change processes, greatly reducing the influence of body forces and allowing the detailed and accurate study of interfacial dynamics. In turn, such improved understanding leads to optimisation of industrial processes and devices involving phase-change, both for space and ground applications. [less ▲]

Detailed reference viewed: 11 (1 ULg)
Full Text
Peer Reviewed
See detailPattern recognition with a digital holographic microscope working in partially coherent illumination
Dubois, Frank; Minetti, Christophe; Monnom, Olivier et al

in Applied Optics (2002), 41(20), 4108-4119

We describe the implementation of the automatic spatial-frequency-selection filter for recognition of patterns obtained with a digital holographic microscope working with a partially coherent source. The ... [more ▼]

We describe the implementation of the automatic spatial-frequency-selection filter for recognition of patterns obtained with a digital holographic microscope working with a partially coherent source. The microscope provides the complex-optical-amplitude field that allows a refocusing plane-by-plane of the sample under investigation by numerical computation of the optical propagation. By inserting a correlation filter in the propagation equation, the correlation between the filter and the propagated optical field is obtained. In this way, the pattern is located in the direction of the optical axis. Owing to the very weak noise level generated by the partially coherent source, the correlation process is shift invariant. Therefore the samples can be located in the three dimensions. To have a robust recognition process, a generalized version of the automatic spatial-frequency-selection filters has been implemented. The method is experimentally demonstrated in a two-class problem for the recognition of protein crystals. (C) 2002 Optical Society of America. [less ▲]

Detailed reference viewed: 28 (3 ULg)
Full Text
Peer Reviewed
See detailHolographic camera with BSO applied to microgravity fluid experiment aboard ISS
Georges, Marc ULg; Joannes, Luc; Thizy, Cédric ULg et al

in Nolte, D.; Salamo, G.; Siahmakoun, A. (Eds.) et al Photorefractive Effects, Materials, and Devices (2001, July)

We present the preliminary development steps of a holographic interferometer using a BSO crystal for the monitoring of fluids experiments under microgravity conditions. This set-up could be included in ... [more ▼]

We present the preliminary development steps of a holographic interferometer using a BSO crystal for the monitoring of fluids experiments under microgravity conditions. This set-up could be included in the Fluid Science Laboratory (FSL, a module dedicated to fluid physics experiment onboard the International Space Station-ISS). Some preliminary studies have been carried out. An optimized configuration has been found allowing a fast recording (50 milliseconds) and large number of readouts (>1000) for analysis of events over a long period without reducing the measurement resolution. We present examples of Rayleigh-Benard convection quantitative measurement performed with a laboratory instrument prototype. [less ▲]

Detailed reference viewed: 18 (2 ULg)
Peer Reviewed
See detailInfluence of surface deformability on weakly nonlinear Marangoni instability
Slavtchev, S. G.; Dauby, Pierre ULg; Lebon, Georgy ULg et al

in Viviani, A. (Ed.) Proceedings of the Second European Symposium. Fluids in Space, Napoli, April 22-26, 1996 (1996)

Detailed reference viewed: 9 (1 ULg)
Full Text
Peer Reviewed
See detailFinite-amplitude regimes of the short-wave Marangoni-Benard convective instability.
Colinet, Pierre; Legros, Jean-Claude; Kamotani, Y. et al

in Physical Review. E : Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics (1995), 52(3), 2603-2616

Detailed reference viewed: 9 (1 ULg)
Peer Reviewed
See detailHEXAGONAL MARANGONI CONVECTION IN A RECTANGULAR BOX WITH SLIPPERY WALLS
Dauby, Pierre ULg; Lebon, Georgy ULg; COLINET, P. et al

in Quarterly Journal Of Mechanics And Applied Mathematics (1993), 46(Part 4), 683-707

Detailed reference viewed: 6 (1 ULg)