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Le Club des Jeunes Sociétaires de la Société Française de Radioprotection a organisé sa première journée scientifique en avril 2018, avec pour thème : « Radioprotection : Quelles innovations ? Quel avenir ? ». Réunissant plus d’une cinquantaine de participants, cette première journée s’est déroulée en deux temps avec des présentations plénières le matin et des ateliers de réflexion l’après-midi portant sur la manière dont l’innovation peut contribuer à la progression ainsi qu’à l’avenir de la radioprotection. Cet article présente les principaux éléments ressortis lors des discussions de ces deux ateliers. Les échanges ont mis en avant la nécessité de prendre en compte le développement des nouvelles technologies et d’en étudier leurs possibles applications aux champs de la radioprotection, que ce soit dans le domaine médical ou de la surveillance environnementale. Mais au-delà, les participants ont plus particulièrement insisté sur le besoin de déployer des outils innovants se plaçant au service de la promotion d’une culture de radioprotection et d’un meilleur partage des données. Pour ces deux enjeux, différentes actions ont été proposées et constituent ainsi des pistes d’actions dont le Club des Jeunes Sociétaires pourrait s’emparer à l’avenir.

The presentation will give the state of the art and the results of the last advances obtained in the growth, the characterization and the implementation of three kinds of rare-earth doped halide laser crystals: Pr 3+ doped fluorides, Yb 3+ doped CaF 2 and its isotypes, and Er 3+ and Pr doped chloride and bromide KPb 2 Cl 5 and Tl 3 PbBr 5 . Keywords: Rare-earth, crystal, laser 1. INTRODUCTION While fiber, semiconductor and nonlinear optical materials no w offer an increasing number of possibilities for various types of applications, rare-earth doped crystals, eventually used in association with the latter, still remain the standard in most of the efficient and high power/hi gh energy solid state laser sources, an d, among these, some particular rare-earth doped halides have very specific properties and advantages. Three kinds of rare-earth doped halide materials, eith er already confirmed or being developed for specific laser systems, have been studied in our laboratory a nd will be presented in this communication: (i) Pr

This paper addresses the experimental study of hot jets impingement on a concave wall. Both low and high Mach number conditions have been investigated. Infrared thermography is used to measure the wall temperature evolution during the heating. This temperature mapping provides the boundary condition necessary to solve the transient heat equation in the wall. From this, heat transfer and Nusselt number are derived and their behaviour compared to literature on the subject when possible. Finally, a correlation of Nusselt versus Reynolds, Prandtl and the nozzle to wall distance is proposed. In order to prevent the airplane performances reduction caused by ice particles entering the engine during the flight, some small anti-icing impinging jets of hot air taken from the combustion chamber are commonly designed. Due to the engine geometry, the hot jets impact on a concave wall. This study is justified by the fact that few literature exists on the subject, at least for high Mach number conditions. Moreover, in order to get experimental results accounting for the complexity of the real configuration, one has to reproduce as far as possible the design of the industrial injection system. A preliminary bibliographical analysis [1, 11] has pointed out the relevant parameters governing the heat transfer in jet impingement for experimental devices presenting some similarities with the present configuration. Although the effects of the Reynolds or Prandtl numbers have been well documented, other parameters, such as the distance between the nozzles and the impact wall, the wall curvature or the Mach number have to be investigated. The study has then been divided in two parts: in a first step, low Mach number have been studied in order to compare with the literature on the subject. Then, the study has been carried out in the real industrial configuration, with Mach numbers about 0.9. The present paper is hinged as follows: chapter 2 presents the experimental set-up including the two injection systems (low and high Mach number) and the measurement means. Chapter 3 presents the results and a short discussion. Then a brief conclusion and future prospects end the manuscript. 2. Experimental set-up An overview of the experimental set-up is presented in Figure 1. The test section is made up a round pipe of diameter 100 mm providing air at flow rates ranging from 0.15 to 3 kg/s at a generating pressure of 10 bar. The air can be heated before entering the test section by means of a 570 kW electric heater. A system of manual and control valves ensure the required flow rate. Two sensors record the flow pressure and temperature. The test section length (several tens of pipe diameter) has been designed to ensure the flow stability. The injection system is mounted on a diffuser. Moreover, a row of honeycombs breaks the large eddies, ensuring by this way a low turbulence level in the inlet of the injection system.

Nous avons realise une experience permettant de mesurer la variation de la polarisabilite des ions Cr 3+ dans le LiSAF lorsqu'ils passent de l'etat fondamental 4 A 2 a l'etat excite 4 T 2 . Cette variation de polarisabilite est a l'origine d'un effet de lentille de population non-lineaire dependant du temps.

Phosphorylated polystyrene derivatives with different compositions in phosphate groups were shown to be either recognized as phospholipidic or as DNA-like surfaces by antibodies from Systemic Lupus Erythematosus patients. In order to check whether these polymers were able to interact with Vitamin K-dependent coagulation factors, phosphorylated resins of various compositions in phosphate groups were assessed with regard to their interactions with Factor II, one of the Vitamin K-dependent factors. These studies were performed either in the presence or the absence of calcium ions, and with or without albumin precoating of the polymers. The results show that the affinity of the protein for the polymer is increased in the presence of calcium ions and depends on the composition of the polymer. The protein-polymer interactions involve the formation of binary or ternary complexes and the domains of predominance of these complexes were determined as a function of the calcium ion concentration in the assay. This allowed us to propose optimal conditions for Factor II purification by highly specific liquid chromatography using phosphorylated polystyrene resins of given compositions as stationary phases.