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Mit Wirkung zum 1. März 2020 wird eine nicht-namentliche, laborbasierte Meldepflicht gemäß § 7 Abs. 3 IfSG auf den Nachweis von Infektionen mit N. gonorrhoeae mit verminderter Empfindlichkeit gegenüber Azithromycin, Cefixim oder Ceftriaxon eingeführt. Wie das Epidemiologische Bulletin 10/2020 ausführt ist dabei bereits die verminderte Empfindlichkeit gegen nur eines der drei angegebenen Antibiotika ausreichend und verpflichtet zur Meldung. Zur Meldung verpflichtet sind in Deutschland diagnostizierende Labore. Darüber hinaus sind die behandelnden Ärzte und Ärztinnen zur Ergänzung weiterer klinischer und epidemiologischer Angaben verpflichtet.

International audience; On October 1, 2018, 452 nuclear water reactors were operating in the world mainly of second generation (PWR or BWR). The first third generation reactors, EPR and AP1000, have just started in China, and 2 two other ones should start next year in Europe. All these reactors produce spent fuel. Some countries have decided to manage this spent fuel as a final waste. In France, a reprocessing of this fuel is carried out in order to separate the uranium and the plutonium remaining in this spent fuel (96% of the total mass of the spent fuel) and reused as MOX fuel. Only 4% of the spent fuel is sent in to the final waste. Reprocessed uranium is stored as a strategic resource whereas plutonium is reused once in MOX fuel. Today, only a mono-recycling of the Pu plutonium is implemented, because of the difficulties to use it a second time in the REPPWR, mainly due to its isotopic composition. Only a reactor with a fast neutron spectrum, for example a Sodium Fast Reactor (SFR), makes the multi-recycling of the plutonium efficient by taking advantage of a higher ratio of fission vs over capture. This strategy was validated by reprocessing MOX assemblies from the French Phenix SFR, and by remanufacturing fresh fuel from the recycled Pu that was irradiated again in Phenix. This experiment demonstrates the feasibility of this actinides recycling by fast reactors. Molten Salt Reactors (MSR) with a fast neutron spectrum would also be potentially able to burn this waste while producing energy. The final performance obtained by burning plutonium or final waste is fairly comparable for any fast reactor. But on the other hand, the MSRs would allow this operation to be achieved in one step, through a continuous multi-recycling and without cumbersome operations to make new fuel assemblies, which entails considerable time and money savings. A concept of fast MSR of 3000 MWt, the MSFR (Molten Salt Fast Reactor) has been studied in France since 15 years by the CNRS and then further developed within European projects. The main technical choices for this reactor, used for this simulation, are explained. Several options are given on the way to use the MSFR as a burner of final products today available after reprocessing. In the first case, the reactor is used as burner of available depleted uranium and plutonium oxide recovered from the reprocessing. These products are fluorinated and introduced into the reactor to achieve criticality. The evolution of the composition of the salt during the operation is given as well as the periodic additions made, and the corresponding consumption by TWh produced. The evolution of the composition of other specific elements that could alter the physico-chemical properties of the salt or the neutronic performances of the reactor (such as the lanthanides) are also given since a specific treatment of the salt has to be developed to extract them. The same exercise is repeated in a second case with the assumption that a reprocessing of a spent MOX has been made that gives a new composition of the plutonium. In Finally in a third option, all the minor actinides (americium, curium and neptunium) are recovered and recycled together, with uranium and plutonium. The possible consumption of waste by TWh produced is determined. Changes in the composition of salt over time give also an idea of the quantities of products to be extracted by salt treatment. In conclusion, this paper gives quantitative estimations of the possibilities to operate a MSR in the U/Pu fuel cycle using only the available products obtained by reprocessing the spent nuclear fuel of a fleet of second-or third-generation water reactors.

International audience

International audience; The CNRS has focused R&D e˙orts on the development of a new reactor concept called the Molten Salt Fast Reactor (MSFR). The MSFR, characterized by a circulating liquid fuel and a fast neutron spectrum, has been identified as a very interesting long term alternative to solid fuelled fast neutron systems in the Gen4 International Forum.MSRs are liquid-fuelled reactors so that they are flexible in terms of operation or design choices, but they are very di˙erent in terms of design and safety approach compared to solid-fuelled reactors. The MSFR system includes three di˙erent circuits: the fuel circuit, the intermediate circuit and the power conversion circuit, together with normal and emergency draining tanks and on-site fuel processing units. This paper will focus on the new designs developed for the fuel circuit and the emergency draining system of the MSFR in the frame of the SAMOFAR European project. The fuel circuit, defined as the circuit containing the fuel salt during power generation, includes the core cavity and the recirculation/cooling sectors. These new designs result from physical and preliminary safety studies such as for the fuel circuit optimizing the use of the molten salt both as fuel and coolant, defining the operating procedures and minimizing the fuel leakage risks. Additional requirements are considered for the emergency draining system to be able to confine the fuel and to evacuate the residual heat over very long time periods (months) with no human intervention and to guaranty that under no circumstance the salt may reach criticality in this area.

ISBN 978-4-89047-167-6; International audience; Molten salt reactors are liquid-fueled reactors so thatthey are flexible in terms of operation (load-followingcapabilities…) or design (core geometry, fuel composition,specific power level…) choices, but they are very differentin terms of design and safety approach compared to solidfueledreactors. Such reactors call for a new definition oftheir operating procedures. Dedicated studies areperformed in the frame of the European SAMOFAR (SafetyAssessment of Molten Salt Fast Reactors) project ofHorizon2020. This paper focuses on the behavior of theMSFR fuel circuit in interaction with the intermediatecircuit. It is devoted to the start-up procedure of the MSFR,including the description of the proposed procedure, apresentation of the approach to criticality and thereactivity measurement during the filling of the core, andfinally studies of accident scenarios (overcooling,reactivity insertion) at low power during the divergencestep of the MSFR, highlighting the very good behavior ofthe reactor to such abnormal transients.

International audience