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International audience; Raman spectroscopy is an efficient technique to study the irradiation damage in nuclear materials [1]. Indeed it is possible to investigate the microstructural modifications and to monitor the damage build-up. In order to observe the dynamic evolution of materials under irradiation, in situ Raman setup has been developed on the triple beam chamber of the JANNUS-Saclay irradiation facility. The sample evolution can thus be followed by Raman spectroscopy during single, dual or triple ion beams irradiation. Irradiation damages of several nuclear materials under single ion beam have already been investigated by in situ Raman at JANNUS facility UO2 as nuclear fuel [1-2], SiC [1,3] and Zircaloy as cladding materials [1] and B4C as neutron absorber [4]. It appears that Raman spectroscopy is a good technique to study on-line crystalline phase changes or amorphization of irradiated iono-covalent solids. Moreover, the use of dual ion beam irradiation coupled with in situ Raman has highlighted combined effects of nuclear (Sn) and electronic (Se) energy losses, which can induce additive damage production (as in ZrO2) or competitive recovery processes (as in SiC), in good agreement with Rutherford backscattering channelling (RBS/C) measurements [3].This paper will give a review of these results and present the new in situ Raman results for single and double ion beam irradiations. A particular emphasis will be given to the synergetic Se/Sn effects.[1] S. Miro et al., J. Raman Spectrosc., 45, 481 (2015).[2] C. Onofri et al., NIM B, 371, 51 (2016).[3] L. Thome et al., JAP, 117, 105901 (2015).[4] D. Gosset et al. JNM, 476, 198 (2016).

University of Alicante assisted in meeting the publication costs of this article. The redox process undergone by the electrochemically synthesized poly(2,2-dithiodianiline), poly(DTDA), has been examined in acetonitrile-water mixtures by electrochemical and spectroscopic techniques. The spectroscopic properties of this material are equivalent to those exhibited by the chemically synthesized one. The polymeric structure displays a ladder structure, with S-S bonds serving as interconnections between two adjacent polyaniline chains. The kinetic reversibility of the RS–SR 2RS− reaction is very poor for the DTDA monomer species, and this irreversibility is retained in the polymeric material. According to the results presented, the hypothesis that poly(DTDA) could display a high energy density due to the simultaneity of the leucoemeraldine emeraldine and dithiolate disulfide electrochemical transformations does not seem justified. Ministerio de Ciencia y Tecnología (MAT2004-1479); Generalitat Valenciana (GV06-106).