Conveners
Poster
- Daniel Grolimund (Paul Scherrer Institute, Swiss Light Source)
Ms
Annamária Kéri
(Hungarian Academy of Sciences Centre for Energy Research)
20/05/2014, 17:30
Actinides in Environmental and Life Sciences
Poster
Argillaceous rocks are considered in most European countries as suitable host rock formations for the deep geological disposal of high-level radioactive waste (HLW). The most important chemical characteristic in this respect is their generally strong radionuclide retention property due to the high sorption capacity. Consequently, the physico-chemical parameters of these processes have to be...
Mr
Tim Pruessmann
(Karlruhe Institute of Technology)
20/05/2014, 17:30
Solution and Coordination Chemistry of the Actinides
Poster
Comparative investigation of N donor ligand and lanthanide/actinide partitioning complexes from the metal and ligand point of view
T Prüßmann1, MA Denecke1,4, A Geist1, J Rothe1, P Lindqvist-Reis1, NL Banik1, B Schimmelpfennig1, D Fellhauer1, C Apostolidis3, O Walter3, DR Batchelor1, P Nagel1, S Schuppler1, K Kvashnina2, T Vitova1
1 Karlsruhe Institute of Technology (KIT), P.O. Box...
Dr
Thomas Dumas
(CEA)
20/05/2014, 17:30
Solution and Coordination Chemistry of the Actinides
Poster
The comprehension of the actinides affinity for interest ligands has been a pivotal issue. The difference in interaction between N-donors ligands and O-donor ligands is a hint on the selectivity difference between trivalent and tetravalent actinides. The study of molecules featuring both N and O-donor functions may be a way to reach a better understanding. Thus, the poly-amino-carboxylate...
Dr
Daniel Fröhlich
(Physikalisch-Chemisches Institut, Universität Heidelberg, Germany)
20/05/2014, 17:30
Solution and Coordination Chemistry of the Actinides
Poster
The long-term storage of high-level nuclear waste will be applied in deep geological formations, different host rock formations (salt, clay, crystalline formations) are investigated throughout Europe [1]. Due to their long half- lives, the long-term radiotoxicity will be determined by the transuranium elements (Np, Pu, Am) included in the waste materials. Therefore, a well-funded knowledge of...
Dr
Andrew Duffin
(Pacific Northwest National Laboratory)
20/05/2014, 17:30
Actinides in Environmental and Life Sciences
Poster
There is a great variety of secondary uranium minerals. In spite of water molecules associated with these minerals, they can be classified by their oxygen K-edge x-ray absorption spectra, opening the door for advanced molecular and isotopic uranium analysis.
Mr
Sebastian Bahl
(Karlsruhe Institute of Technology (KIT))
20/05/2014, 17:30
Actinides in Environmental and Life Sciences
Poster
One option to dispose solid Mo(VI)- and Cs(I)-rich residual material sedimenting in storage tanks for high level liquid waste (HLLW) is immobilisation in borosilicate glass. Due to its low solubility in glass melts, Mo(VI) tends to form separate molybdate-rich phases during the vitrification process [1]. These phases may crystallise during melt cooling and are able to incorporate radionuclides...
Dr
Vallerie Ann Samson
(PSI)
20/05/2014, 17:30
Solid State Chemistry and Physics of the Actinides
Poster
Zirconium alloys are extensively used as materials in a broad range of technical applications in various types of nuclear facilities. The mechanical and physico-chemical properties of these alloys can be tuned by modifying the chemical composition, mainly by the addition of dopants. Empirical studies have revealed that one of the key properties, the corrosion resistance, can be significantly...
Mr
Florent Lebreton
(CEA Marcoule)
20/05/2014, 17:30
Solid State Chemistry and Physics of the Actinides
Poster
Over the last decades, the application of XAS (X-ray Absorption Spectroscopy) to actinide-bearing materials has proven to be a very reliable method to obtain valuable information on these oxides, through a coupled insight into oxidation states and local structure. Experiments were notably performed on UO2+x, U1 yPuyO2±x and U1-yAmyO2±x compounds [1-4]. Concerning the latter for instance, an...
Melanie Chollet
20/05/2014, 17:30
Solid State Chemistry and Physics of the Actinides
Poster
Because actinides (An) are typically accept various oxidation states, and because fuel redox conditions evolve with burn-up, others oxides than stoichiometric AnO2 are formed during irradiation.
In this work, neptunium chemical state and local environment in stoichiometric and oxidized (U0.9Np0.1)O2(+x) fresh samples were obtained by X-ray absorption spectroscopy at the NpLIII edge (17610...
Mr
Ivan Pidchenko
(Institute for Nuclear Waste Disposal)
20/05/2014, 17:30
Solution and Coordination Chemistry of the Actinides
Poster
In this work four electrochemically aqueous plutonium (Pu) species prepared in perchloric acid solution at different oxidation states (III, IV, V, VI) as well as Pu(IV) colloids are characterized for the first time by Pu L3 and M5 edge high energy resolution X-ray absorption near-edge structure spectroscopy (HR-XANES). A Johann type five-analyzer crystal spectrometer recently installed and...
Dr
Daiju Matsumura
(Japan Atomic Energy Agency)
20/05/2014, 17:30
Facility Reports and Upcoming Techniques
Poster
Dispersive XAFS technique is unique approach for the real-time-resolved observation of chemical reaction. X rays with wide-band energy are created by a curved crystal and counted by a space-resolved detector after sample transmission. We can obtain XAFS spectra without any mechanical motion of crystal or detector. We have developed dispersive XAFS observation system at BL14B1 (Japan Atomic...
Dr
Enzo CURTI
(Paul Scherrer Institut)
20/05/2014, 17:30
Solid State Chemistry and Physics of the Actinides
Poster
In the context of the FIRST-Nuclides collaborative project (EURATOM FP7 programme) Paul Scherrer Institut is carrying out leaching experiments on high-burnup UO2 spent nuclear fuel (SNF) from Swiss nuclear power plants, in order to determine the short-term release of easily accessible nuclides (instant release fraction, shortly IRF). The focus is on nuclides such as 129I, 135Cs, 14C and 79Se....
Mr
Ugras Kaplan
(Karlsruhe Institute of Technology - INE)
20/05/2014, 17:30
Actinides in Environmental and Life Sciences
Poster
Due to its long half-life Pu has a significant contribution to the radiotoxicity of spent nuclear fuel in a repository after long periods of storage. Pu exhibits a complicated redox chemistry, where up to three oxidation states can coexist under environmentally relevant conditions [1]. In order to predict the migration behavior of Pu after its potential release from a repository of spent...
Mr
Prashanta Jonathan Benjamin Rosemann
(Institute of Nuclear Chemistry, Johannes Gutenberg-Universität Mainz, 55099 Mainz, Germany)
20/05/2014, 17:30
Actinides in Environmental and Life Sciences
Poster
For the long-term safety of nuclear waste repositories and a possible migration of the relevant transuranium actinide Np into the environment, the study of the interaction of Np with clays is of highest importance, since argillaceous rocks are under consideration as potential host rocks or at least as backfill material in high-level nuclear waste repositories in countries like Switzerland and...
Yulia Podkovyrina
(Southern Federal University)
20/05/2014, 17:30
Theoretical and Modeling Tools
Poster
Deep understanding of mobilization/immobilization mechanisms of uranium in the environment is essential for safety assessment of a long-term nuclear waste repository. For example the soluble in groundwater U(VI) can be immobilized by sorption or incorporation into minerals [1]. Iron oxide nanoparticles are abundant in the environment and play a major role in sorption and redox behavior of U. ...
Aurelie Jeanson
(CNRS)
20/05/2014, 17:30
Actinides in Environmental and Life Sciences
Poster
In the wake of the Fukushima accident, it is of great importance to assess the mechanisms governing radionuclide impact on the environment (particularly the biosphere) and to unravel the molecular processes underlying actinide transport and deposition in tissues. Most data available on the interaction of actinides with biological systems are based on physiological or biokinetic measurements,...
Prof.
Yury Teterin
(National Research Center "Kurchatov Institute")
20/05/2014, 17:30
Solid State Chemistry and Physics of the Actinides
Poster
The quantitative analysis of the x-ray photoelectron spectral (XPS) structure of americium dioxide AmO2 was done in the valence electrons binding energy range taking into account binding energies and spectral structures of the core electronic levels (~35 - 1250 eV) and the relativistic calculation data for the AmO812- (D4h) cluster reflecting americium close environment in AmO2. The...
Dr
Kathy DARDENNE
(Karlsruhe Institute of Technology, Institute for Nuclear Waste Disposal (KIT-INE))
20/05/2014, 17:30
Solid State Chemistry and Physics of the Actinides
Poster
The Karlsruhe Reprocessing Plant (WAK) was operated from 1971 to 1991 as a pilot facility for reprocessing of spent nuclear fuels from German pilot reactors and commercial power plants. Reprocessing activities resulted in ~60 m3 of highly active waste concentrates (HAWC) stored on-site in liquid form. An important step in the current decommissioning of the WAK was the HAWC vitrification in the...
Prof.
Yury Teterin
(National Research Center "Kurchatov Institute")
20/05/2014, 17:30
Solid State Chemistry and Physics of the Actinides
Poster
The quantitative analysis of the x-ray photoelectron spectral (XPS) structure of Сs2PuO2Cl4 single crustal containing the plutonyl group PuO22+ was done in the valence electrons binding energy range 0 - ~35 eV taking into account binding energies and spectral structures of the core electronic levels (~35 - 1250 eV) and the relativistic calculation data for the PuO2Cl42- (D4h) cluster...
