-The spallation residues produced in the bombardment of 56 F e at 1.5, 1.0, 0.75, 0.5 and 0.3 A GeV on a liquid-hydrogen target have been measured using the reverse kinematics technique and the Fragment Separator at GSI (Darmstadt). This technique has permitted the full identification in charge and mass of all isotopes produced with cross-sections larger than 10 −2 mb down to Z = 8. Their individual production cross-sections and recoil velocities at the five energies are presented. Production cross-sections are compared to previously existing data and to empirical parametric formulas, often used in cosmic-ray astrophysics. The experimental data are also extensively compared to different combinations of intra-nuclear cascade and de-excitation models. It is shown that the yields of the lightest isotopes cannot be accounted for by standard evaporation models. The GEMINI model, which includes an asymmetric fission decay mode, gives an overall good agreement with the data. These experimental data can be directly used for the estimation of composition modifications and damages in materials containing iron in spallation sources. They are also useful for improving high precision cosmic-ray measurements.
LA-ICP-MS allows precise, relatively fast, and spatially resolved measurements of elements and isotope ratios at trace and ultratrace concentration levels with minimal sample preparation. Over the past few years this technique has undergone rapid development, and it has been increasingly applied in many different fields, including biological and medical research. The analysis of essential, toxic, and therapeutic metals, metalloids, and nonmetals in biomedical tissues is a key task in the life sciences today, and LA-ICP-MS has proven to be an excellent complement to the organic MS techniques that are much more commonly employed in the biomedical field. In order to provide an appraisal of the fast progress that is occurring in this field, this review critically describes new developments for LA-ICP-MS as well as the most important applications of LA-ICP-MS, with particular emphasis placed on the quantitative imaging of elements in biological tissues, the analysis of heteroatom-tagged proteins after their separation and purification by gel electrophoresis, and the analysis of proteins that do not naturally have ICP-MS-detectable elements in their structures, thus necessitating the use of labelling strategies.
We present an extensive overview of production cross sections and kinetic energies for the complete set of nuclides formed in the spallation of 136 Xe by protons at the incident energy of 1 GeV per nucleon. The measurement was performed in inverse kinematics at the GSI fragment separator. Slightly below the BusinaroGallone point, 136 Xe is the stable nuclide with the largest neutron excess. The kinematic data and cross sections collected in this work for the full nuclide production are a general benchmark for modeling the spallation process in a neutron-rich nuclear system, where fission is characterized by predominantly mass-asymmetric splits.
An IR-femtosecond laser ablation ICPMS coupling was used to investigate the influence of the high repetition rate on elemental fractionation effects for the analysis of silicate glass SRM NIST 610. First, elemental fractionation inherent to the ICP was minimised by working on wet plasma conditions which had greater tolerance to mass loading and demonstrated a higher robustness compared to dry plasma conditions. Because of the use of a narrow laser beam producing small craters (17 mm in diameter), a special arrangement of pulses was used to perform resulting craters of 100 mm diameter. The ablation strategy developed in this work consisted in a series of concentric circle trajectories ablated at high repetition rates by moving the laser beam rapidly thanks to a scanning beam device. Two scanner speeds (0.25 mm s À1 and 1.5 mm s À1), five laser repetition rates (from 0.1 kHz to 10 kHz) and three fluence values (5 J cm À2 , 14 J cm À2 , and 25 J cm À2) were investigated in detail. For this purpose, critical elemental ratios (namely 238 U/ 232 Th, 208 Pb/ 238 U, and 66 Zn/ 65 Cu) of aerosols produced by fs-LA of silicate glass were studied to evaluate the impact of the different laser parameters on elemental fractionation. No heating zones or preferential evaporation of elements were found depending on the repetition rate employed. However, particle-size-fractionation was measured during the ablation of the sample surface, and this effect was reduced by using a high repetition rate as well as a high scanner speed which allow the dilution of the large particles coming from the surface layer with finer particles coming to deeper levels. Additionally, the ablation rate induced by the selected ablation strategy had a low influence on fractionation effects due to the high robustness of the ICP plasma and, on the other hand, fractionation indices were not particularly affected by the laser repetition rate although they could be improved by the use of high fluence values. Finally, it could be stressed that no differences on the structure of the aerosol particles collected on membrane filters were found depending on the ablation parameters.
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