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International audience; The effect of Silver-Indium-Cadmiun (SIC) control rod on the transport of volatile fission products (I, Cs,Mo) in conditions of a Reactor Coolant System under NPP severe accident was investigated within threesemi-integral tests in a thermal gradient tube. The experiments addressed separately the effect of eachSIC element. Nature of transported and deposited species was investigated by ICP MS, ESEM-EDX,Raman Microspectrometry, XRD and XPS techniques.For the first time, numerous metallic molybdates involving SIC components were evidenced. The formationof such metallic molybdates competes with the formation of Cs-molybdate and may in certainconditions strongly reduce the scavenging effect of Mo towards Cs. As a result the nature of transportediodine can be strongly modified, compared to chemical systems involving only Mo, Cs and I. The dataobtained are useful to guide what species have to be added in the thermodynamic database used inthe SA simulation software. more...

The aim of this study was to investigate the effect of 3 different surface plasma treatments on the immobilization of β-galactosidase on a fibrous PET nonwoven membrane. Two methods 1. Entrapment in a thin calcium alginate coating and 2. Direct sorption, were used to immobilize the enzyme. The three different plasma treatments for surface activation of PET nonwovens were: 1. Air atmospheric DBD plasma, 2. Cold remote plasma-CRP with 100% N2 and 3.- CRP with a mixture of N2/O2 gases. Plasma treatment of the PET fiber surface increased the quantity of immobilized enzyme using the entrapment method, and the degree of alginate film cross-linking highly influenced the enzyme activity. Highest enzyme activity was reached for the PET treated with air atmospheric plasma and cross-linked with 0.25 g/l of CaCl2. With the direct sorption method, greater amounts of enzyme were immobilized as compared to the entrapment method, but a considerable proportion of enzyme lost their catalytic activity. Only with the CRP N2/O2 plasma treatment, up to 90% of sorbed enzyme maintained their activity. Reusability study showed that for the optimized entrapment method, a progressive decrease in activity was observed after each use cycle. With the optimized sorption method using N2/O2 CRP plasma, no decrease in enzyme activity was detected, and the immobilized enzyme could be used over more than 15 cycles. more...