BACKGROUND AND OBJECTIVES The determination of the carbon isotope ratio in androgen metabolites has been previously shown to be a reliable, direct method to detect testosterone misuse in the context of antidoping testing. Here, the variability in the 13C/12C ratios in urinary steroids in a widely heterogeneous cohort of professional soccer players residing in different countries (Argentina, Ita...

The applicability and limitations of sulphur isotope ratio as a nuclear forensic signature have been studied. The typically applied leaching methods in uranium mining processes were simulated for five uranium ore samples and the n(34S)/n(32S) ratios were measured. The sulphur isotope ratio variation during uranium ore concentrate (UOC) production was also followed using two real-life sample set...

Silicon isotope ratios of a typical CAI from the Leoville carbonaceous chondrite, obtained in situ by laser ablation MC-ICPMS, together with existing Mg/Mg data, reveal a detailed picture of the astrophysical setting of CAI melting and subsequent heating. Models for the chemical and isotopic effects of evaporation of the molten CAI are used to produce a univariant relationship between PH2 and t...

In the present study the effects of the detector dead-time and its uncertainties on the accuracy and uncertainty of isotope dilution mass spectrometry (IDMS) were considered through an interlaboratory study on the analysis of low-alloy steel by using an ICP-sector field mass spectrometer. Also, an optimized mixing ratio of the sample and the spike to obtain highly precise results was theoretica...