The Experts below are selected from a list of 267 Experts worldwide ranked by ideXlab platform
Pierre H. Dixneuf - One of the best experts on this subject based on the ideXlab platform.
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Ruthenium-allenylidene complexes and their specific behaviour
Coordination Chemistry Reviews, 2004Co-Authors: Stéphane Rigaut, Daniel Touchard, Pierre H. DixneufAbstract:Abstract This review presents recent innovations in the field of stoichiometric transformations of Ruthenium-allenylidene systems via synthesis and at the frontier of material science and catalysis. It especially shows new routes to the first bis-allenylidene-Ruthenium and diRuthenium complexes, trisallenylidene Ruthenium triskelia, the use of Ruthenium-allenylidene as precursors for alkenylcarbynes and indenylidenes, and the involvement of allenylidenes in the building of dinuclear Ruthenium bridges with a C 7 carbon-rich bridge.
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Ruthenium-allenylidene complexes and their specific behaviour
Coordination Chemistry Reviews, 2004Co-Authors: Stéphane Rigaut, Daniel Touchard, Pierre H. DixneufAbstract:This review presents recent innovations in the field of stoichiometric transformations of Ruthenium-allenylidene systems via synthesis and at the frontier of material science and catalysis. It especially shows new routes to the first bis-allenylidene-Ruthenium and diRuthenium complexes, trisallenylidene Ruthenium triskelia, the use of Ruthenium-allenylidene as precursors for alkenylcarbynes and indenylidenes, and the involvement of allenylidenes in the building of dinuclear Ruthenium bridges with a C-7 carbon-rich bridge. (C) 2004 Elsevier B.V. All rights reserved.
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Ruthenium-allenylidene complexes and their specific behaviour
Coordination Chemistry Reviews, 2004Co-Authors: Stéphane Rigaut, Daniel Touchard, Pierre H. DixneufAbstract:International audienceThis review presents recent innovations in the field of stoichiometric transformations of Ruthenium-allenylidene systems via synthesis and at the frontier of material science and catalysis. It especially shows new routes to the first bis-allenylidene-Ruthenium and diRuthenium complexes, trisallenylidene Ruthenium triskelia, the use of Ruthenium-allenylidene as precursors for alkenylcarbynes and indenylidenes, and the involvement of allenylidenes in the building of dinuclear Ruthenium bridges with a C-7 carbon-rich bridge. (C) 2004 Elsevier B.V. All rights reserved
Christian Ekberg - One of the best experts on this subject based on the ideXlab platform.
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impact of ag and nox compounds on the transport of Ruthenium in the primary circuit of nuclear power plant in a severe accident
Annals of Nuclear Energy, 2017Co-Authors: Ivan Kajan, Teemu Kärkelä, Unto Tapper, Ari Auvinen, Leenasisko Johansson, Melany Gouello, Henrik Rameback, Stina Holmgren, Christian EkbergAbstract:Ruthenium is a semi-volatile element originating as a fission product in nuclear reactors that can be released in case of a severe nuclear accident. In this work, the impact of atmosphere composition on the transport of Ruthenium through the primary circuit was examined. The effects of silver nanoparticles representing aerosols and NO2 gas as a product of air radiolysis were studied. Quantification of Ruthenium transported both as gas and aerosol was performed. Chemical composition of Ruthenium species was evaluated. The transport of gaseous Ruthenium through the facility increased significantly when NO2 gas was fed into the atmosphere. When both silver aerosols and NO2 were fed into the atmosphere, the transport of Ruthenium in gaseous and aerosol forms was promoted. It was concluded that the composition of atmosphere in the primary circuit will have a notable effect on the speciation of Ruthenium transported into the containment building during a severe accident and thus on the potential radioactive release to the environment.
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Ruthenium transport in an RCS with airborne CsI
Progress in Nuclear Energy, 2017Co-Authors: Teemu Kärkelä, Ivan Kajan, Unto Tapper, Ari Auvinen, Christian EkbergAbstract:Ruthenium is one of the most radiotoxic fission products which can be released from fuel as Ruthenium oxides in an air ingress accident at a nuclear power plant. In this study it was found that the transport of the released Ruthenium oxides through a reactor coolant system into the containment building is significantly affected by the atmospheric conditions. Airborne CsI increased the transport of gaseous Ruthenium compared with that in a pure air atmosphere. The overall transport of Ruthenium increased with temperature. In order to understand the behaviour of Ruthenium in accident conditions, it is important to widen the experimental conditions from pure air/steam atmospheres to more realistic mixtures of prototypic gases and aerosols.
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Deposition of RuO4 on various surfaces in a nuclear reactor containment
Journal of Nuclear Materials, 2009Co-Authors: Joachim Holm, Henrik Glänneskog, Christian EkbergAbstract:During a severe nuclear reactor accident with air ingress, Ruthenium can be released from the nuclear fuel in the form of Ruthenium tetroxide. Hence, it is important to investigate how the reactor containment is able to reduce the source term of Ruthenium. The aim of this work was to investigate the deposition of gaseous Ruthenium tetroxide on aluminium, copper and zinc, which all appear in relatively large amounts in reactor containment. The experiments show that Ruthenium tetroxide is deposited on all the metal surfaces, especially on the copper and zinc surfaces. A large deposition of Ruthenium tetroxide also appeared on the relatively inert glass surfaces in the experimental set-ups. The analyses of the different surfaces, with several analytical methods, showed that the form of deposited Ruthenium was mainly Ruthenium dioxide. (C) 2009 Elsevier B.V. All rights reserved.
Stéphane Rigaut - One of the best experts on this subject based on the ideXlab platform.
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Ruthenium-allenylidene complexes and their specific behaviour
Coordination Chemistry Reviews, 2004Co-Authors: Stéphane Rigaut, Daniel Touchard, Pierre H. DixneufAbstract:Abstract This review presents recent innovations in the field of stoichiometric transformations of Ruthenium-allenylidene systems via synthesis and at the frontier of material science and catalysis. It especially shows new routes to the first bis-allenylidene-Ruthenium and diRuthenium complexes, trisallenylidene Ruthenium triskelia, the use of Ruthenium-allenylidene as precursors for alkenylcarbynes and indenylidenes, and the involvement of allenylidenes in the building of dinuclear Ruthenium bridges with a C 7 carbon-rich bridge.
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Ruthenium-allenylidene complexes and their specific behaviour
Coordination Chemistry Reviews, 2004Co-Authors: Stéphane Rigaut, Daniel Touchard, Pierre H. DixneufAbstract:This review presents recent innovations in the field of stoichiometric transformations of Ruthenium-allenylidene systems via synthesis and at the frontier of material science and catalysis. It especially shows new routes to the first bis-allenylidene-Ruthenium and diRuthenium complexes, trisallenylidene Ruthenium triskelia, the use of Ruthenium-allenylidene as precursors for alkenylcarbynes and indenylidenes, and the involvement of allenylidenes in the building of dinuclear Ruthenium bridges with a C-7 carbon-rich bridge. (C) 2004 Elsevier B.V. All rights reserved.
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Ruthenium-allenylidene complexes and their specific behaviour
Coordination Chemistry Reviews, 2004Co-Authors: Stéphane Rigaut, Daniel Touchard, Pierre H. DixneufAbstract:International audienceThis review presents recent innovations in the field of stoichiometric transformations of Ruthenium-allenylidene systems via synthesis and at the frontier of material science and catalysis. It especially shows new routes to the first bis-allenylidene-Ruthenium and diRuthenium complexes, trisallenylidene Ruthenium triskelia, the use of Ruthenium-allenylidene as precursors for alkenylcarbynes and indenylidenes, and the involvement of allenylidenes in the building of dinuclear Ruthenium bridges with a C-7 carbon-rich bridge. (C) 2004 Elsevier B.V. All rights reserved
Ivan Kajan - One of the best experts on this subject based on the ideXlab platform.
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impact of ag and nox compounds on the transport of Ruthenium in the primary circuit of nuclear power plant in a severe accident
Annals of Nuclear Energy, 2017Co-Authors: Ivan Kajan, Teemu Kärkelä, Unto Tapper, Ari Auvinen, Leenasisko Johansson, Melany Gouello, Henrik Rameback, Stina Holmgren, Christian EkbergAbstract:Ruthenium is a semi-volatile element originating as a fission product in nuclear reactors that can be released in case of a severe nuclear accident. In this work, the impact of atmosphere composition on the transport of Ruthenium through the primary circuit was examined. The effects of silver nanoparticles representing aerosols and NO2 gas as a product of air radiolysis were studied. Quantification of Ruthenium transported both as gas and aerosol was performed. Chemical composition of Ruthenium species was evaluated. The transport of gaseous Ruthenium through the facility increased significantly when NO2 gas was fed into the atmosphere. When both silver aerosols and NO2 were fed into the atmosphere, the transport of Ruthenium in gaseous and aerosol forms was promoted. It was concluded that the composition of atmosphere in the primary circuit will have a notable effect on the speciation of Ruthenium transported into the containment building during a severe accident and thus on the potential radioactive release to the environment.
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Ruthenium transport in an RCS with airborne CsI
Progress in Nuclear Energy, 2017Co-Authors: Teemu Kärkelä, Ivan Kajan, Unto Tapper, Ari Auvinen, Christian EkbergAbstract:Ruthenium is one of the most radiotoxic fission products which can be released from fuel as Ruthenium oxides in an air ingress accident at a nuclear power plant. In this study it was found that the transport of the released Ruthenium oxides through a reactor coolant system into the containment building is significantly affected by the atmospheric conditions. Airborne CsI increased the transport of gaseous Ruthenium compared with that in a pure air atmosphere. The overall transport of Ruthenium increased with temperature. In order to understand the behaviour of Ruthenium in accident conditions, it is important to widen the experimental conditions from pure air/steam atmospheres to more realistic mixtures of prototypic gases and aerosols.
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transport and containment chemistry of Ruthenium under severe accident conditions in a nuclear power plant
2016Co-Authors: Ivan KajanAbstract:During a severe nuclear accident volatile elements and elements readily forming volatile compounds are the main concern regarding the release of radioactive material to the environment. As Ruthenium is prone to form volatile oxides under severe nuclear accident conditions as well as having radiotoxic isotopes, it is one of the more important elements during such an accident. In this work the chemical behavior of Ruthenium during the transport in the reactor cooling system and the chemistry of Ruthenium within the containment was studied. Studies on Ruthenium transport included the effect of temperature, air-radiolysis products and aerosols on the quantity and chemical form of transported Ruthenium during an accident. During the experiments the temperature had significant effect both release and transport of Ruthenium. Different air radiolysis products affected both quantity and physical form of the transported Ruthenium. The other part of the studies was focused on the chemistry of Ruthenium within the containment. These experiments aimed at the interaction of Ruthenium tetroxide with metallic (Al, Cu, Zn) and epoxy paint covered surfaces within the containment. Ruthenium had great affinity towards these surfaces that led to the formation of Ruthenium rich deposits and thus a clear retention. Chemical characterization as well as quantification of these deposits was obtained. The effect of gamma radiation on the formed Ruthenium deposits was shown and re-volatilized fractions of Ruthenium under different atmospheres and received doses were determined decreasing the retention significantly. Studies focused on interaction of Ruthenium tetroxide with iodine-covered surfaces showed its ability to oxidize iodine deposit and re-volatilize iodine from the aluminum and zinc metals. Iodine covered surfaces were also proved to be an effective trap of Ruthenium within the containment. Data obtained from these studies can be utilized for the better understanding of severe accident phenomenology and behavior of radionuclides during an accident.
Daniel Touchard - One of the best experts on this subject based on the ideXlab platform.
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Ruthenium-allenylidene complexes and their specific behaviour
Coordination Chemistry Reviews, 2004Co-Authors: Stéphane Rigaut, Daniel Touchard, Pierre H. DixneufAbstract:Abstract This review presents recent innovations in the field of stoichiometric transformations of Ruthenium-allenylidene systems via synthesis and at the frontier of material science and catalysis. It especially shows new routes to the first bis-allenylidene-Ruthenium and diRuthenium complexes, trisallenylidene Ruthenium triskelia, the use of Ruthenium-allenylidene as precursors for alkenylcarbynes and indenylidenes, and the involvement of allenylidenes in the building of dinuclear Ruthenium bridges with a C 7 carbon-rich bridge.
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Ruthenium-allenylidene complexes and their specific behaviour
Coordination Chemistry Reviews, 2004Co-Authors: Stéphane Rigaut, Daniel Touchard, Pierre H. DixneufAbstract:This review presents recent innovations in the field of stoichiometric transformations of Ruthenium-allenylidene systems via synthesis and at the frontier of material science and catalysis. It especially shows new routes to the first bis-allenylidene-Ruthenium and diRuthenium complexes, trisallenylidene Ruthenium triskelia, the use of Ruthenium-allenylidene as precursors for alkenylcarbynes and indenylidenes, and the involvement of allenylidenes in the building of dinuclear Ruthenium bridges with a C-7 carbon-rich bridge. (C) 2004 Elsevier B.V. All rights reserved.
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Ruthenium-allenylidene complexes and their specific behaviour
Coordination Chemistry Reviews, 2004Co-Authors: Stéphane Rigaut, Daniel Touchard, Pierre H. DixneufAbstract:International audienceThis review presents recent innovations in the field of stoichiometric transformations of Ruthenium-allenylidene systems via synthesis and at the frontier of material science and catalysis. It especially shows new routes to the first bis-allenylidene-Ruthenium and diRuthenium complexes, trisallenylidene Ruthenium triskelia, the use of Ruthenium-allenylidene as precursors for alkenylcarbynes and indenylidenes, and the involvement of allenylidenes in the building of dinuclear Ruthenium bridges with a C-7 carbon-rich bridge. (C) 2004 Elsevier B.V. All rights reserved