34 research outputs found
Plutonium in the environment: key factors related to impact assessment in case of an accidental atmospheric release
International audienceThis paper deals with plutonium and key factors related to impact assessment. It is based on recent work performed by CEA which summarize the main features of plutonium behaviour from sources inside installations to the environment and man, and to report current knowledge on the different parameters used in models for environmental and radiological impact assessment. These key factors are illustrated through a case study based on an accidental atmospheric release of Pu in a nuclear facility
TRLFS study on the speciation of uranium in seepage water and pore water of heavy metal contaminated soil
Les microsystèmes d'analyse de radionucléides au service de la chimie analytique verte
Contyributeurs : M. Aubert, C. Bresson, C. Caussignac, F. Chartier, H., Isnard, I. Laszak, M. Marie, C. Mariet, A. Nonell,G. Stadelmann, L. Vio, A. Bruchet, G. Hellé (Thèses)National audiencePrésentation d'études réalisées au LANIE sur les microsystèmes d'analyse
Spéciation aqueuse des lanthanides dans le cycle du combustible et l'environnement
National audienc
On-site Detection and Identification of Chemical Warfare Agents with portable LIBS system
International audienceLaser Induced Breakdown Spectroscopy (LIBS) offers a unique in-situ capability to detect chemical contamination on any surface by a laser interrogation of the material. It consists in focusing a pulsed laser beam onto the surface of the material to initiate a plasma and recording the UV-Visible emission spectrum from that plasma. This spectrum is a signature of the chemical elements present in the ablated volume of the sample. LIBS is a fully optical method which allows to perform real time, in situ and remote analysis without any sample preparation.Portable LIBS instruments have been developed and enable on-site measurements with immediate response. Our team has a deep experience in LIBS and has developed a methodology for Chemical Warfare Agents (CWA) detection and identification, based on the use of an EasyLIBSTM (IVEA Solution) instrument. Indeed, CWA are organic molecules with elemental fingerprints (Chlorine, Fluorine, Phosphorus, Sulfur and/or Arsenic), which are particularly suited for their identification by LIBS. The results of our measurements on real CWA will be presented and discussed
Evaluation of the efficacy of a portable LIBS system for detection of CWA on surfaces
International audienc
LIBS probe for in-situ material characterization
International audienceThe needs in terms of chemical characterizations for dismantling operations are first the inventory of materials either for appropriate and safe waste management or for refining neutron calculations and secondly to map the contamination. In both cases, a large number of measurements must be carried out. Given the difficulties of sampling management (storage, handling and transport) or overload of analytical laboratories, in-situ analysis methods without sampling, such as LIBS (Laser Induced Breakdown Spectroscopy), are to be preferred.Moreover the limited access of nuclear facilities being decommissioned renders an adaptable remote LIBS analysis device very suitable for determining the chemical composition of materials. The LIBS device that we have developed includes a portable probe connected both to the laser and to the spectrometer by two optical fibers (Figure 1). This instrument has been already used for some applications. For example, tests were carried out in the a uranium manufacturing facility (CEA Cadarache, ATUE) during decommissioning of the building to determine uranium contamination fixed on the surface of the walls (Figure 2). The LIBS system was also used to characterize on site the nature of alloys constituting various parts of UF6 containers, providing an instant response to the operator.It is planned, in interaction with CEA/DPAD, to realize in-situ steel grade determination of some parts located into the G1 reactor (CEA Marcoule). Thanks to its versatility other possibilities of uses could be envisaged with this device to match the needs of dismantling operators
A Simple and Adaptive Methodology to use a Commercial Solvent Extraction Microsystem as Screening Tool Validation with the U-TBP Chemical System
International audienceThe solvent extraction of a U (VI) present at several g.L-1 from the aqueous phase (HNO3) = 3 M to the organic one (30 percent TBP) involves a change of the viscosity of the two phases during the extraction process in microsystem. This shifts the position of the interface between the two phases and then affects the quality of the separation at the outlet of the microsystem. The aim of this study is to present a simple method to stabilize the quality of the separation by controlling the interface position during solvent extraction in microsystem. First, a study at low concentration is operated in order to set flow rates and contact time that allow optimal parallel flows and mass transfer. Second, the influence of the high grade concentration (up to 140 g.L-1) of solute on the flows and extraction yield is studied
Sulfate Complexation of Trivalent Lanthanides Probed by Nanoelectrospray Mass Spectrometry and Time-Resolved Laserinduced Fluorescence Spectroscopy
Conférence du 18 au 23 Septembre 2005. Communication par affiche