In this thesis, we exploited optical and X-ray pump-probe methods in a synergistic approach to study the interplay of the electronic, spin and structural degrees of freedom in two class of complex systems relevant for solar energy conversion applications: ...
Pt-group metal (PGM)-free catalysts of the Me-N-C type based on abundant and inexpensive elements have gained importance in the field of oxygen reduction reaction (ORR) electrocatalysis due to their promising ORR-activities. Their insufficient stability, h ...
Crystallization timescales in subvolcanic systems and the consequences of interaction between ascending magmas and gases remain largely unconstrained, as do links between these processes and monitoring signals at restless volcanoes. We apply diffusion chro ...
Mineralogy, chemistry and spatial distribution of phyllomanganates, found in abundance at the bottom of thick Ni-laterite deposits, were established on dislocated vein-infillings showing banded and fibrous patterns (i.e. colloforms with rows of tiny boxwor ...
Magnesium partitioning between metal and silicate was experimentally investigated between 34 and 138GPa, 3,500 and 5,450K using laser-heated diamond anvil cells. The 22 measurements are combined with previously published data (total of 49 measurements) to ...
Planetesimal were the first planetary objects to form in the solar system, which later grew to make the proto-planets. Most of these bodies were differentiated as a result of internal heating. Several differentiated bodies have, then, been accreted followi ...
It has been known for decades that certain aqueous salt solutions of LiCl and LiBr readily form glasses when cooled to below approximate to 160 K. This fact has recently been exploited to produce a "salty" high-pressure ice form: When the glass is compress ...
Discontinuous Galerkin (DG) method is presented for numerical modeling of melt migration in a chemically reactive and viscously deforming upwelling mantle column. DG methods for both advection and elliptic equations provide a robust and efficient solution ...
The unique achondrite NWA 7325 is an unusual olivine gabbro composed chiefly of calcic plagioclase (An(85-93)), diopsidic pyroxene (En(50.1-54.0) Wo(44.8-49.3) Fs(0.6-1.3)), and forsteritic olivine (Fo(97)). It is Al and Mg-rich and Fe and Na-poor and disp ...
The thesis focuses on the study of the performance of TBMs in highly jointed and faulted rocks. Despite the great production rates recorded in favourable ground conditions, the TBM advance can be significantly slowed down in limiting geological situations ...
Asteroid 4 Vesta seems to be a major intact protoplanet, with a surface composition similar to that of the HED (howardite-eucrite-diogenite) meteorites(1-4). The southern hemisphere is dominated by a giant impact scar(5), but previous impact models(6-8) ha ...
Chemical weathering of Mg, Ca-silicates and alumino-silicates contributes significantly to the drawdown of atmospheric CO2 over long time scales. The present work focuses on how this mode of weathering may change in the presence of free-living bacteria in ...
Clenet et al. (2011) have developed an adapted version of the Modified Gaussian Model (MGM). The improvements allow the characterization of spectra of olivine-pyroxene(s) mixtures, addressing both modal composition and individual minerals chemical composit ...
Shergottites and Chassignites practiced major deformation effects whose nature, magnitude and relevance were controversially evaluated and disputatively debated. Our studies of many shocked shergottites present, contrary to numerous previous reports, ample ...
Understanding the formation of materials at elevated temperatures is critical for determining their final properties. Synchrotron-based X-ray tomographic microscopy is an ideal technique for studying such processes because high spatial and temporal resolut ...
The Howardite-Eucrite-Diogenite (HED) suite is a family of differentiated meteorites that provide a unique opportunity to study the differentiation of small bodies. The likely parent-body of this meteorite group, (4) Vesta is presently under study by the D ...