Ion beam therapy, unlike conventional radiotherapy, allows a proper localization of the energy deposition in tumors and thus spares the surrounding healthy organs. Recently, the use of radiosensitizers, including high-Z nanoparticles (Ag, Au, Gd), was proposed to enhance the effects of ionizing radiation. The mechanism responsible for such an efficiency enhancement is the important release of electrons from the nanoparticles (NPs) triggered either by the primary ion beam or by secondary charged particles created along the track. These electrons may then interact directly with biomolecules. Even at low energy (below ionization threshold), electrons can induce molecular damage via Dissociative Electron Attachment (DEA). They can also produce highly reactive species such as hydroxyl radicals (OH) from the surrounding water molecules via radiolysis or DEA. Within the IMAGERI project, we propose to quantify this low energy electron emission by providing doubly differential absolute cross sections in order to shed light on the physical processes responsible for the enhancement effect of radiosensitizers in ion beam therapy. Therefore a new experimental set-up dedicated to the measurement of absolute cross-sections for electron emission from size-controlled isolated NPs after ion irradiation will be built. The collimated beam of metallic NPs formed using an aerodynamic lens will cross orthogonally the projectile ion beam produced by the GANIL beamlines. Emitted electrons will be extracted and analyzed in energy and angle by a velocity map imaging (VMI) spectrometer. By monitoring the target density, projectile ion beam intensity and the beams overlap with the use of a quartz crystal microbalance and an ion beam profiler, we will be able to estimate absolute cross sections for electron emission. Such cross sections will be measured and compared for various size (from nm to few tenths of nm) and elements (Ag, Au, Pt and Gd) of the NPs. Furthermore, typical ion beam kinetic energies of the Bragg-peak (MeV) and of secondary particles (keV) will be investigated. This project aims to better understand the intrinsic properties of NPs under irradiation and the physical processes leading to the efficiency enhancement of radiation damage. It will provide data from which a broad scientific community will benefit: from experimental and theoretical physics to chemistry and biology. Absolute cross sections will be used as benchmark measurements for theory and input in Monte-Carlo computational modeling of the passage of charged particles through matter (such as GEANT4-DNA). Comparative studies between different radiosensitizers may also trigger new experiments in radiobiology. In the long run, it can impact the society as a better understanding of the fundamental processes can lead to an optimization in the choice of radiosensitizers to make ion beam therapy techniques more efficient.

The next few decades are likely to witness a gradual shift from an economy strongly based on crude oil to more diverse sources of energy and chemicals. Hydrocarbons, obviously remain essential for many areas of chemistry. However, synthetic hydrocarbons can be derived from methanol and ethanol via the so-called METH (Methanol/Ethanol to Hydrocarbons conversion) processes. The implementation of an economically-viable methanol economy will however depend on the development of new or improved catalytic processes and more efficient catalysts. The main objective of the « HiZeCoke » project is to understand the detailed relationships between the textural and acidic properties of hierarchical porous zeolites and their catalytic performances, in particular the resistance to deactivation by carbonaceous deposits. The modeling of the activity of hierarchical porous materials and their mode of deactivation is of paramount importance for a rational design of improved METH catalysts. This important topic is currently studied by many foreign groups and a few papers have recently been published on this subject. However, the overall understanding of the properties of such materials is still very sketchy. A number of key questions remain to be answered, for instance: • Is the catalytic activity improvement a mere consequence of the mesoporosity created? • What is the effect of the synthesis or post synthesis procedures on the nature, quantity and location of defects in zeolite framework (silanol nests, extra-framework Al, distribution of Al between the micro- and mesoporous networks …)? • What is the role of the external and mesoporous surfaces on the performances? • What is the relative role of the mesopores on the coke formation and its nature? • How is the adsorption and diffusion of reactants/products affected by the newly created mesoporosity ? • To which extent is there a modification of the acidic properties (concentration, strength, location) during the creation of mesopores? • How many active sites are working during the catalytic reaction on the various catalysts? • Is it possible to control and engineer the size of the mesopore in post synthesis treatments like desilication? Designing model materials with controlled external surface activity and active sites distribution will help to answer these crucial questions. Namely, we will have to provide a clear distinction between external (i.e., formed in the mesoporous or external crystal surface) and internal coke (inside the micropores) and their relative impact on the performance of the catalyst. This will result in a further improvement of the catalyst performances (time on stream, conversion and selectivity). In the course of the project, we expect that catalytic testing, coke analysis and combined spectroscopic approaches to understand the origin of catalyst deactivation will greatly help designing efficient, stable and selective catalyst for METH reactions.

Flash (ultra-rapid) sintering is a new sintering approach allowing sintering in mere seconds. This project addresses the main inherent heating instabilities, microstructural inhomogeneity and regulation issues of this abrupt process. Flash sintering will be applied to advance sintering techniques such as spark plasma sintering (SPS) and microwave sintering. The main goal is to combine pulsed electrical current or microwave irradiation and/or high pressure to decrease the flash sintering temperature and attain a better control of this process and the sintered microstructures. The multiphysics simulation/modeling will be investigated, on the one hand, for the understanding of all coupled physical parameters, and on the other hand, for the study of the underlying flash sintering mechanisms. This project strategy is based on five tasks organized in a certain order to reach the project objectives. The first task consists of the establishment of the multiphysics numerical tool which needs to be adapted to the ultra-rapid sintering conditions. Then, this numerical tool will be employed for the determination of the favorable ultra-rapid sintering experimental conditions, the regulation of this abrupt process, and the homogeneity of the physical fields for the scaling up of this process. The last task is dedicated to the fundamental sintering aspect of ultra-rapid sintering and its modeling. This task will be developed along with the others. The ambition of this project is the establishment of stable and reproducible experimental conditions for the ultra-rapid sintering of metals to dielectric parts (up to 30 mm); each developed sintering process will come with a comprehensive multiphysics model which encompasses all the main physical phenomena.