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Abstract: This study investigates the relevance of several soil chemical extractions (calcium chloride, acetic acid, citric acid and a four-step sequential procedure) and predicted free metal ion activities in the soil solution to characterise the transfer of trace metals (Cd, Pb, and Zn) from soil to snail soft tissues over a large smelter-impacted area (Metaleurop Nord, Nord-Pas-de-Calais, France). The study was first performed on six snail species together and then specifically on Cepaea sp. and Oxychilus draparnaudi. When the six species were considered together, the accumulation of metals depended mostly on the species. When significant, total or extractable metal concentrations, or the predicted free ion activities, accounted for less than 7% of the variation of the metal concentrations in the snail tissues. Species-specific analyses showed that extractable concentrations explained approximately 25% of the variation of the metal concentrations in O. draparnaudi, and up to 8% in Cepaea snails. When using total soil concentrations and soil properties as explanatory variables, the models were generally slightly better, explaining up to 42% of the variance. The soil extraction procedures and predicted free ion activities used in this study did not accurately estimate the metal transfer from soil to snails and could not be used in risk assessment. [Copyright &y& Elsevier]

Straight-chain N,N-dihexyloctanamide (DHOA) and branched-chain N,N-di(2-ethylhexyl)isobutyramide (D2EHIBA) have been identified as promising alternatives to tri-n-butylphosphate (TBP) for the reprocessing of spent uranium based fuels, and selective extraction of 233U from irradiated thorium fuels, respectively. The present work deals with the effects of different hydrodynamic parameters such as viscosity, density, and interfacial tension (IFT) on the phase-separation time (PST) under uranium and thorium loading conditions. The IFT values have been determined under varying experimental conditions such as the aqueous nitric acid concentration, n-dodecane purity, ligand concentration, and thorium/uranium loading conditions. These studies have suggested that the quality of n-dodecane affects the IFT values of different solutions. The IFT values of D2EHIBA changed marginally (23.3 ± 0.9 mNm-1) against THOREX feed solution for the wide range of D2EHIBA concentration (0.1-1.0 M). However, IFT, viscosity, and PST values increased with uranium loading of 1.1 M DHOA. These studies suggested that a lower phase-disengagement rate with increased uranium loading was mainly due to the increased viscosity of the loaded 1.1 M DHOA solution. [ABSTRACT FROM AUTHOR]

Abstract: When a lead beam is collimated in the CERN LHC some of the ions fragment in the collimators causing problems downstream. For design purposes the fragmentation probability needs to be assessed. At LHC energies (; the Lorentz-factor is the total energy of an ion in units of its rest energy) electromagnetic dissociation dominates the fragmentation in medium to heavy target materials. Due to the extended range of the interaction at high energies, atomic screening affects the dissociation in the LHC collimators. We determine the magnitude of the reduction in cross section relative to the unscreened case for various collimator materials and find a significant effect for tungsten, the heaviest candidate planned for use. [Copyright &y& Elsevier]

Describes the production of metallic ions using an electron cyclotron resonance ion source in France. Acceleration of the ions for nuclear physics experiments; Need of accelerators for stable beams; Delivery of stable beams by direct ion plasma sputtering.

The article offers information related to a study conducted by a scientist Ryszard Lobinski and colleagues at the National Research Council of France (CNRS), Pau, France. The study shows that metal ions play an important role in the body where they interact with genes, proteins and metabolites. It provides information that metallomics is the systematic study of metallomes and the interactions and functional connections of metal ions and their species with genes, proteins, metabolites.