Search results for "isotopic composition"
showing 8 items of 18 documents
Nuclear Forensics: A methodology applicable to Nuclear Security and to Non-Proliferation
2011
Nuclear Security aims at the prevention and detection of and response to, theft, sabotage, unauthorized access, illegal transfer or other malicious acts involving nuclear material". Nuclear Forensics is a key element of nuclear security. Nuclear Forensics is defined as a methodology that aims at re-establishing the history of nuclear material of unknown origin. It is based on indicators that arise from known relationships between material characteristics and process history. Thus, nuclear forensics analysis includes the characterization of the material and correlation with production history. To this end, we can make use of parameters such as the isotopic composition of the nuclear material…
Production of hypernuclei in peripheral relativistic ion collisions
2013
Within a dynamical and statistical approach we study the main regularities in production of hypernuclei coming from projectile and target residues in relativistic ion collisions. We demonstrate that yields of hypernuclei increase considerably above the energy threshold for Lambda hyperons, and there is a saturation for yields of single hypernuclei with increasing the beam energy up to few TeV. Production of specific hypernuclei depend very much on the isotopic composition of the projectile, and this gives a chance to obtain exotic hypernuclei that may be difficult to reach in traditional hypernuclear experiments. Possibilities for the detection of such hypernuclei with planned and available…
Estimating the chance of success of archaeometric analyses of bone: UV-induced bone fluorescence compared to histological screening
2011
Abstract For most archaeometric analyses on archaeological bone material, such as the determination of the isotopic composition or genetic approaches, an advanced degree of diagenetic alteration can make designated analysis impossible. Since the lack of a positive signal is mostly seen only after time consuming and cost intensive sample processing, the need for an easy-to-apply screening method that allows a pre-selection of samples containing well-preserved biomolecules is obvious. In this study, we visually determined the UV-induced autofluorescence of 76 horse bone cross-sections, all from prehistoric archaeological sites of varying environmental and chronological background. In order to…
Trace-element composition and stable-isotope ratio for discrimination of foods with Protected Designation of Origin
2009
We review the literature on authentication of foods with Protected Designation of Origin (PDO) from their trace-element composition or stable-isotope ratios in order to evaluate the state of the art of this field and to identify the main parameters of analytical techniques and chemometric-data treatments that permit accurate discrimination of samples of different geographical origins and with different characteristics.
Spectrochemical Rubidium-Strontium Method for Geological Age Determination
1960
The age values of lepidolites from South Africa and from Varutrask as well as that of a microcline from Varutrask have been determined and are discussed in connection with determination according to the potassium-argon method, applied to the same materials A method is suggested which allows the spectrochemical determination of Rb and Sr with sufficient accuracy. The isotopic composition is determined by means of a Fabry-Perot etalon and hollow-cathode excitation, investigating the hyper-fine structure of the Sr line at 4078 A.
Etude de l'évolution de la pollution atmosphérique par le CO2 dans la ville de Cotonou utilisant la signature isotopique des graminées C4
2007
8 pages; International audience
The use of shallow dripwater as an isotopic marker of seepage in karst areas: A comparison between Western Sicily (Italy) and the Harz Mountains (Ger…
2013
Abstract The isotopic signature of slow-flowing dripwater collected in caves located in Western Sicily (Italy) was determined for evaluating its possible use as an isotopic tracer of the local groundwater recharge. These spot measures were compared with a longer series of local rain and spring compositions and with other samples taken, under different hydrogeological conditions, in caves of the Harz Mountains (Northern Germany). The slow flowing dripwater from Sicily showed δ 18 O/δD ratios similar to those of local rain and groundwater, demonstrating that these three are all parent waters. A parallel similarity was found in the vertical isotopic gradient (Δδ 18 O) of the three groups of wa…
Mount Etna: Geochemical signals of magma ascent and unusually extensive plumbing system
2003
] FiveyearsofgasmonitoringfromselectedsitessuggestthatMtEtna’splumbingsystemismuchmoreextensivethanpreviously reported. It extends at least 40 km SW from thevolcano’s boundary along the NE-SW regional fault, whereit discharges about 200 tons/day of gas, containing heliumwith mantle-type isotopic composition. Synchronousvariations of