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Ispra, Italy

The Institute for Transuranium Elements is a nuclear research institute in Karlsruhe, Germany. The ITU is one of the seven institutes of the Joint Research Centre, a Directorate-General of the European Commission. The ITU has about 300 staff. Its specialists have access to an extensive range of advanced facilities, many unavailable elsewhere in Europe. Wikipedia.

Tositti L.,University of Bologna | Brattich E.,University of Bologna | Cinelli G.,University of Bologna | Cinelli G.,Institute for Transuranium Elements | Baldacci D.,University of Bologna
Atmospheric Environment | Year: 2014

Simultaneous measurements of airborne radionuclides 7Be and 210Pb, together with aerosol mass load PM10, have been routinely carried out at the Global WMO-GAW station of Mt. Cimone (Italy, 2165m a.s.l., 44° 12' N, 10° 42' E) from 1998 to 2011. The experimental activity was started with the purpose of gaining a better understanding of the vertical and horizontal transports taking place at this site affecting the atmospheric chemical composition. The time series of the collected data is presented and discussed in this paper. The 7Be concentrations in this period are in the range 0.05-15.8mBqm-3 with the presence of two distinct relative maxima during winter/spring and summer, suggesting an origin from different physical processes. The 210Pb concentrations collected during the period are in the range 0.05-2.30mBqm-3 and are characterized by a single maximum during the warm period. The 7Be/210Pb ratio was in the range 0.5-127.8 and is characterized by a maximum during the cold period. The frequency distributions of the three parameters and the seasonal/interannual variabilities are investigated and presented. © 2014 Elsevier Ltd.

Vespa M.,Joseph Fourier University | Vespa M.,Institute for Transuranium Elements | Lanson M.,Joseph Fourier University | Manceau A.,Joseph Fourier University
Environmental Science and Technology | Year: 2010

Previous synchrotron X-ray microprobe measurements of Zn speciation in contaminated and uncontaminated soils have identified phyllosilicate as the main sequestration phase. The emphasis now is focused on comparing the nature and properties of neoformed and geogenic phyllosilicate species to understand natural attenuation processes. Refined structural characterization of the two types of Zn-containing phyllosilicate in slightly basic smelter-affected agricultural soils were obtained using a so far unprecedented combination of X-ray microscopic techniques, including fluorescence (μ-XRF), absorption (μ-EXAFS), and diffraction (μ-XRD), and X-ray bulk-sensitive techniques, including powder and polarized EXAFS spectroscopy. The unpolluted and polluted species are both dioctahedral smectites, but the first which contains minor Zn (ca. 150 mg/kg) is aluminous and Fe-free, and the second, which contains several hundreds to a few thousands mg/kg Zn depending on the distance to the smelter and wind direction, is ferruginous with an average Fe/Al atomic ratio of 1.1 ± 0.5. The Zn2+ and Fe3+ in the neoformed smectite are derived from the weathering of ZnS, ZnO, FeS2, and ZnFe 2O4 particles from the smelter. These cations diffuse away from their particulate mineral sources and coprecipitate with Al and Si in the soil clay matrix. Zinc sequestration in the octahedral sheet of dioctahedral smectite is potentially irreversible, because this type of phyllosilicate is stable over a large pH range, and the neoformed species is analogous to the native species which formed over time during pedogenesis. © 2010 American Chemical Society.

Kirchner G.,Federal office for Radiation Protection | Bossew P.,Federal office for Radiation Protection | De Cort M.,Institute for Transuranium Elements
Journal of Environmental Radioactivity | Year: 2012

It is shown which information can be extracted from the monitoring of radionuclides emitted from the Fukushima Dai-ichi nuclear power plant and transported to Europe. In this part the focus will be on the analysis of the concentration ratios. While 131I, 134Cs and 137Cs were reported by most stations, other detected radionuclides, reported by some, are 95Nb, 129mTe, 132Te, 132I, 136Cs and 140La. From their activity ratios a mean burn-up of 26.7 GWd/t of the fuel from which they originated is estimated. Based on these data, inventories of radionuclides present at the time of the accident are calculated. The caesium activity ratios indicate emissions from the core of unit 4 which had been unloaded into the fuel storage pool prior to the accident. © 2011 Elsevier Ltd.

Hernandez-Ceballos M.A.,Institute for Transuranium Elements | Garcia-Mozo H.,University of Cordoba, Spain | Galan C.,University of Cordoba, Spain
International Journal of Biometeorology | Year: 2015

The impact of regional and local weather and of local topography on intradiurnal variations in airborne pollen levels was assessed by analysing bi-hourly holm oak (Quercus ilex subsp. ballota (Desf.) Samp.) pollen counts at two sampling stations located 40 km apart, in southwestern Spain (Cordoba city and El Cabril nature reserve) over the period 2010–2011. Pollen grains were captured using Hirst-type volumetric spore traps. Analysis of regional weather conditions was based on the computation of backward trajectories using the HYSPLIT model. Sampling days were selected on the basis of phenological data; rainy days were eliminated, as were days lying outside a given range of percentiles (P95–P5). Analysis of cycles for the study period, as a whole, revealed differences between sampling sites, with peak bi-hourly pollen counts at night in Cordoba and at midday in El Cabril. Differences were also noted in the influence of surface weather conditions (temperature, relative humidity and wind). Cluster analysis of diurnal holm oak pollen cycles revealed the existence of five clusters at each sampling site. Analysis of backward trajectories highlighted specific regional air-flow patterns associated with each site. Findings indicated the contribution of both nearby and distant pollen sources to diurnal cycles. The combined use of cluster analysis and meteorological analysis proved highly suitable for charting the impact of local weather conditions on airborne pollen-count patterns. This method, and the specific tools used here, could be used not only to study diurnal variations in counts for other pollen types and in other biogeographical settings, but also in a number of other research fields involving airborne particle transport modelling, e.g. radionuclide transport in emergency preparedness exercises. © 2014, ISB.

Cinelli G.,Institute for Transuranium Elements | Tondeur F.,ISIB
Journal of Environmental Radioactivity | Year: 2015

The deviations of the distribution of Belgian indoor radon data from the log-normal trend are examined. Simulated data are generated to provide a theoretical frame for understanding these deviations. It is shown that the 3-component structure of indoor radon (radon from subsoil, outdoor air and building materials) generates deviations in the low- and high-concentration tails, but this low-C trend can be almost completely compensated by the effect of measurement uncertainties and by possible small errors in background subtraction. The predicted low-C and high-C deviations are well observed in the Belgian data, when considering the global distribution of all data.The agreement with the log-normal model is improved when considering data organised in homogeneous geological groups. As the deviation from log-normality is often due to the low-C tail for which there is no interest, it is proposed to use the log-normal fit limited to the high-C half of the distribution. With this prescription, the vast majority of the geological groups of data are compatible with the log-normal model, the remaining deviations being mostly due to a few outliers, and rarely to a "fat tail". With very few exceptions, the log-normal modelling of the high-concentration part of indoor radon data is expected to give reasonable results, provided that the data are organised in homogeneous geological groups. © 2015 The Authors.

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