This article presents the synthesis and the blend of bismuth complexes in polystyrene based plastic scintillators. A specific design has enabled the fabrication of a scintillator loaded with up to 17 wt% of bismuth. Tri-carboxylate and triaryl bismuth compounds were used to explore and understand the influence of bismuth loading on the two main criteria of plastic scintillation: light yield and detection efficiency of g-rays. For gamma radiation with an energy <200 keV, bismuth loaded scintillators demonstrate the ability to produce a photoelectric peak (total absorption peak) in pulse height spectra.The increase of interactions due to bismuth doping was quantified and fitted with standard models.Finally the performance of our bismuth loaded scintillators was evaluated to be better than that of a commercial lead loaded counterpart.

In this paper we discuss a comprehensive physical-based model of the PEMFC materials degradation allowing predicting the MEA durability as function of the operation conditions, initial material loadings and electrodes microstructure. The approach, build within a modular multiscale non-equilibrium thermodynamics framework, couples atomistic-based descriptions of catalyst contamination/oxidation/dissolution/ripening, dissolved catalyst migration in the ionomer, C catalyst-support corrosion and chemical PEM degradation, with the degradation-induced nano/microstructural and transport properties (of reactants and charges) evolution. By describing the feedback between the instantaneous performance and the material aging phenomena, the model provides new insights on the competition between the different degradation processes under automotive-operating conditions. The predictive capabilities of our approach are illustrated in this paper through four applicative examples: 1) PtxCoy catalysts degradation 2) competition of PEM and cathode C degradation 3) synergies between anodic CO contamination and PEM and cathode C degradation, and 4) synergies between Pt and C degradation.

Organometallic chemistry has recently gained a lot of attention in the domain of plastic scintillators.Homogenously dispersed metal complexes in a polymer matrix can afford plastic scintillators with unseen abilities. Heavy atom loading is very attractive as it gives access to plastics with increased sensitivity towards elusive radiations such as gamma and neutron. But this comes with a drawback, as heavy atoms tend to quench fluorescence, hence decreasing the scintillation yield. We present here a comprehensive study of this phenomenon with bismuth and gadolinium complexes. We investigate the influence of the ligand nature by varying organometallic and fluorophore concentration to probe their interaction. We also propose an explanation of the difference in behavior between these two metals. These results were applied to the fabrication of large volume loaded plastic scintillators (4100 cm 3 ). Bismuth loaded scintillators displayed characteristics equivalent to lead loaded commercial materials, and gadolinium samples proved to be able to capture thermal neutrons and release gamma rays. of our optimization, large scale loaded PSs (4100 cm 3 ) were synthesized and characterized.

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