PhD in science specialized in Soft Condensed Matter Physics and Synchrotron Radiation, my backround is originally in the field of Materials Science in which I took an Engineering degree followed by a Masters degree in Biological NMR and Crystallograpy.
Furthermore, although most of my
studies were undertaken in France
(except for a year in Ireland some time before),
I took my last year of engineering in Canada and most of the work
during my PhD was carried out in european institution (ESRF).
Ph.D. in physics (2004):
Combined studies of microdeformation by indentation and X-ray microdiffraction applied to polymers.
Physics departement of the Joseph
Fourier University,
Grenoble (France).
European Synchrotron
Radiation Facility (ESRF),
Grenoble (France).
Keywords: synchrotron radiation, X-rays, microdiffraction, small and wide angle X-ray scattering, SAXS, WAXS, crystallography, polymer microstructure, morphology, elastic and plastic deformation, indentation, microhardness, instrumentation, in-situ studies, real-time, polyethylene, PE, polypropylene, PP, Vectra, liquid-crystalline polymers...
A
new instrument was designed (fig.1) in order to perform real-time
studies of micro-deformations (in-situ) using small- and wide-angle
X-ray scattering (SAXS/WAXS) [2]. A
micro-hardness tester (indenter) from
the Anton-Paar company, bearing a Vickers-type diamond tip
(square-based pyramid) was mounted on an Olympus motorized rotating
turet used in optical microscopes. Three Micos motors allow to position
the sample fixed on a diamond support (transparent to X-rays at the
wavelengths used) below the indenter. A control box was interfaced to a
PC and allows to monitor the deformation.
Fig.1: Microindenter setup design (a): the sample is glued on a diamond support (c) mounted on an XYZ translation stage which allows positioning with respect to the Vickers diamond tip (arrow in (c)). A region of interest can be selected online using a set of microscope objectives fixed on the rotating turret (b) and a CCD camera. The device can be mounted on the beamline translation stage for micro X-ray scattering experiments (the beam direction is indicated in (a) by a dotted arrow). Calibration of the X-ray beam position is obtained by replacing the sample-holder by a GaN crystal [2,6].
The integration on the Microfocus Beamline of the ESRF (ID13)
was
undertaken in a second step. Different configurations were tested in
conjunction with small and wide-angle X-ray scattering techniques using
a beam of a few microns in diameter.
This work has allowed to evidence deformation mechanisms on lengthscales of a few tens of nanometers and below in both synthetic and natural semi-crystalline polymers and in other materials [2-6]. A strong texture is induced by the deformation process, which can be evidenced by scanning indented fibres (plastically deformed) in different orientations with respect to the beam. This texture can be described quantitatively by measuring the tilt of the diffraction pattern or the peak broadening and splitting along the azimuth. In this way, it was shown that 2D projection maps of the strain field can be reconstructed and compared in some cases with images of phase transformation induced by the indentation process. In-situ experiments performed on several fibres show that it is also possible to observe elastic deformation mechanisms and quantify its extent. These experiments were the first of a kind, as deformation induced by micro-indentation had never been observed using X-ray microbeams (in-situ) before.
Download
thesis
(pdf):
Outline
(121KO)
Introduction
(95Ko)
Chapter
I
- General background (3812Ko)
Chapter
II
- Instrumental developments (1754Ko)
Chapter
III
- Materials and methods (763Ko)
Chapter
IV
- Results and discussion (3839Ko)
Conclusion
(126Ko)
Appendices
(1943Ko)
Master's in Structural Biology (2000):
Quantum/Molecular mechanics (QMMM) modeling of the PFOR enzyme
Physics departement of the Joseph
Fourier University,
Grenoble (France)
Structural Biology Institute(IBS),
Grenoble (France)
Keywords: numerical modelling, quantum mechanics, molecular mechanics, crystallography, nuclear magnetic resonance (NMR), neutrons diffusion, electron microscopy, structural biology biochemistry.
In order to strenghten and broaden my knowledge in structural biology and programming, I followed lectures of this Master's (DEA by french standards...) in Grenoble, Paris (Orsay) and Strasbourg.
My research was taken at the Molecular Dynamics
Laboratory (LDM)
headed by Martin Field of the Institute of Structural
Biology of Grenoble. The aim was to model the behaviour an enzyme, the
Pyruvate Feredoxin Oxydo
Reductase (PFOR) using a mixed algorithm based on the use of Quantum
Mechanics and Molecular Mechanics (QMMM).
Materials Science Engineering (1999):
Materials Science departement of Polytech'Grenoble,
France (Joseph
Fourier University) & Mc
Master University, Hamilton, Canada
Keywords: polymers, metals, ceramics, glasses, composites, semi-conductors, processing, characterization, electrochemistry, corrosion, quality control, management..
This engineering degree provides a general training in
Materials
Science. All important classes of materials are studied : polymers,
metallurgy, ceramics, composites. This extends to powders, sintered
materials, glasses, magnetic materials, semi-conductors...
Applications can thus focus on design, processing, characterization,
quality control, research and development...
My final year was taken at McMaster University (Ontario, Canada) where
I found additional training in glass science, X-ray charaterization,
spectroscopy. In addition, I also attended lectures in economy,
mineralogy (abstract) and theoretical physics...
This general knowledge allowed me to gain professional insight through
a training at the R&D centre of Federal Mogul (Pont-de-Claix,
France) and a senior thesis at the Brockhouse
Institute
for Material Research (Hamilton, Ontario, Canada) working on the
synthesis and characterization of a new magnetic compound with a
Perovskite type structure [1].
