A5036074745- Radioactive contamination and transfer
- Radioactive element chemistry and processing
- Radioactivity and Radon Measurements
- Nuclear Physics and Applications
- Nuclear Materials and Properties
- Nuclear and radioactivity studies
- Nuclear reactor physics and engineering
- Nuclear physics research studies
- Isotope Analysis in Ecology
- Groundwater flow and contamination studies
- Atomic and Subatomic Physics Research
- Soil and Unsaturated Flow
- Rare-earth and actinide compounds
- Ion-surface interactions and analysis
- Plant Pathogens and Resistance
- Superconducting Materials and Applications
- Radioactive Decay and Measurement Techniques
- Mass Spectrometry Techniques and Applications
- Astro and Planetary Science
- Astrophysical Phenomena and Observations
- Lichen and fungal ecology
- Geology and Paleoclimatology Research
- Graphite, nuclear technology, radiation studies
- Spectroscopy Techniques in Biomedical and Chemical Research
- Radiation Detection and Scintillator Technologies
Karlsruhe Institute of Technology
2015-2022
Federal Office for the Safety of Nuclear Waste Management
2017-2020
University of Vienna
2009-2015
Kerntechnische Entsorgung Karlsruhe (Germany)
2015
Joint Research Centre
2012-2013
University of Campania "Luigi Vanvitelli"
2012
Institute for Technologies Applied to Cultural Heritage
2009
University of Naples Federico II
2009
Abstract Half of the heavy elements including all actinides are produced in r -process nucleosynthesis, whose sites and history remain a mystery. If continuously produced, Interstellar Medium is expected to build-up quasi-steady state abundances short-lived nuclides (with half-lives ≤100 My), nucleosynthesis. Their existence today’s interstellar medium would serve as radioactive clock establish that their production was recent. In particular 244 Pu, actinide nuclide (half-life=81 can place...
Abstract Isotopic ratios of radioactive releases into the environment are useful signatures for contamination source assessment. Uranium is known to behave conservatively in sea water so that a ratio uranium trace isotopes may serve as superior oceanographic tracer. Here we present data on atomic $$^{233}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msup><mml:mrow/><mml:mrow><mml:mn>233</mml:mn></mml:mrow></mml:msup></mml:math> U/ $$^{236}$$...
Natural clay rocks, such as Opalinus Clay (OPA), are considered potential host rocks for the disposal of high-level nuclear waste due to their ability limit radionuclide transport molecular diffusion. Laboratory studies related investigation diffusion behavior usually performed at relatively high concentrations. For instance, U in has been investigated concentrations low approximately 10-4 mol·m-3 clay. This study addresses 233U(VI) OPA down ultratrace 10-9 using accelerator mass...
236U was analyzed in an ombrotrophic peat core representing the last 80 years of atmospheric deposition and a minerotrophic sample from interglacial period. The determination at levels 107 atoms/g possible by using ultraclean laboratory procedures accelerator mass spectrometry. vertical profile 236U/238U isotopic ratio along represents first observation bomb peak terrestrial environment. A constant level anthropogenic with average (1.24 ± 0.08) × 10–6 top layers observed. Comparing...
The neutron capture cross sections of the main uranium isotopes, (235)U and (238)U, were measured simultaneously for keV energies, first time by combining activation technique atom counting reaction products using accelerator mass spectrometry. New data, with a precision 3%-5%, obtained from mg-sized natural samples energies an equivalent Maxwell-Boltzmann distribution kT ∼ 25 broad energy peaking at 426 keV. cross-section ratio (235)U(n,γ)/(238)U(n,γ) can be deduced in spectrometry directly...
236U, 237Np, and Pu isotopes 243Am were determined in ground- seawater samples at levels below ppq (fg/g) with a maximum sample size of 250 g. Such high sensitivity was possible by using accelerator mass spectrometry (AMS) the Vienna Environmental Research Accelerator (VERA) extreme selectivity recently improved efficiency significantly simplified separation chemistry. The use nonisotopic tracers investigated order to allow for determination 237Np 243Am, which isotopic either are rarely...
The isotopic composition of plutonium (239Pu, 240Pu, 241Pu and 242Pu) was investigated in a ∼0.5 m long peat core from an ombrotrophic bog (Black Forest, Germany) using clean room procedures accelerator mass spectrometry (AMS). This sophisticated analytical approach ultimately needed to detect reliably the Pu concentrations present samples at femtogram (fg) attogram (ag) levels. mean 240Pu/239Pu ratio 0.19 ± 0.02 (N = 32) layers, representing approximately last 80 years, good agreement with...
VERA, the Vienna Environmental Research Accelerator, is especially equipped for measurement of actinides, and performs a growing number measurements on environmental samples. While AMS not optimum method each particular plutonium isotope, possibility to measure 239Pu, 240Pu, 241Pu, 242Pu 244Pu same sputter target great simplification. We have obtained first result global fallout value 244Pu/239Pu = (5.7 ± 1.0) × 10-5 based soil samples from Salzburg prefecture, Austria. Furthermore, we...
Recent major advances in Accelerator Mass Spectrometry (AMS) at the Vienna Environmental Research (VERA) regarding detection efficiency and isobar suppression have opened possibilities for analysis of additional long-lived radionuclides ultra-low environmental concentrations. These radionuclides, including 233 U, 135 Cs, 99 Tc, 90 Sr, will become important oceanographic tracer application due to their generally conservative behavior ocean water. In particular, isotope ratios U/ 236 U 137 Cs/...
Actinide isotopes are present in environmental samples at ultra-trace levels ( 236 U concentration is quoted to be on the order of pg/kg or fg/kg). Their detection requires resolution mass spectrometry (MS) techniques, but only accelerator (AMS) has sensitivity required. In perform isotopic ratio measurements actinides, such as U/ 238 U, an upgrade Center for Isotopic Research Cultural and Environmental Heritage (CIRCE) Caserta, Italy, been performed. The system was originally equipped...
The assessment of the radiological impact a decommissioning Nuclear Power Plant is presented here through results an environmental monitoring survey carried out in area surrounding Garigliano Plant. levels radioactivity soil, water, air and other matrices are shown, which {\alpha}, {\beta} {\gamma} activity equivalent dose rate measured. Radioactivity samples from analyzed then compared to those control zone situated more than 100 km away. Moreover, comparison made with previous held 2001....
In the frame of studies on safe disposal nuclear waste, there is a great interest for understanding migration behavior 99Tc. 99Tc originating from energy production and global fallout shows environmental levels down to 107 atoms/g soil (∼2 fg/g). Extremely low concentrations are also expected in groundwater after diffusion through bentonite constituting technical barrier waste disposal. The main limitation sensitivity mass spectrometric analysis background its stable isobar 99Ru. For...
The multiactinide analysis with accelerator mass spectrometry (AMS) was applied to samples collected from the run 13-05 of Colloid Formation and Migration (CFM) experiment at Grimsel Test Site (GTS). In this in situ radionuclide tracer test, environmental behavior 233U, 237Np, 242Pu, 243Am investigated a water conductive shear zone under conditions relevant for nuclear waste repository crystalline rock. concentration actinides GTS groundwater determined AMS over 6 orders magnitude ∼15 pg/g...
The impact of the Fukushima accident on nuclear fuel cycle back-end is obvious. In present paper various options and their environment will be presented in view this new perspective. partitioning transmutation (P&T) concept direct disposal including a very long intermediate storage certainly revisited with respect to safety considerations; here instant release fraction (IRF) long-term stability matrix under real repository conditions are highly relevant. Furthermore released radionuclides...