Measurement Strategies

Abstract

Designing an appropriate measurement strategy for a particular analytical question is not always obvious, since a number of factors have to be considered, whereby some of them might be difficult to define. A set of key questions generally precede the experimental design in analytical measurements and help to choose the measurement strategy, which is fit for the intended use -in the particular case of the content of this book -either for quantification, elemental ratio or isotope ratio analyses, accordingly.

A combined TIMS and ICP-MS study for Th0.5Np0.5O2 thorium neptunium mixed oxide analysis

“…Each mixture was evaporated after preparation, and then dissolved again in 40 µL of 1 mol L -1 nitric acid. This step provided the complete homogenization of the (sample -spike) mixture [12]. 1 µL (about 500 ng of Th) of this final solution was deposited onto a filament for each individual measurement.…”

“…measurement trueness and precision) [6,10,11]. The principle of ID is adding to the sample a known amount of spike with a known mass fraction and a known isotopic composition (that must be different than that of the sample analyzed) [12,13]. The sample -spike mixture isotope ratio reflects the sample analyte mass fraction.…”

Development and comparison of two high accuracy methods for uranium concentration in nuclear fuel: ID-TIMS and K-edge densitometry

“…The ID-TIMS require an optimum mixture isotope ratio (RMix), which can be determined theoretically [18]. The ID-TIMS parameters other than the mixture isotope ratio ([U]T, mT, mS, (235)T, (238)S, RS or RT) depend only on the sample and spike characteristics and on the mixture masses.…”

Application of non-traditional stable isotopes in analytical ecogeochemistry assessed by MC ICP-MS - A critical review

“…The detected, erroneous values of isotope ratios can derive from many different effects in a mass spectrometer from sample introduction, ion formation, ion extraction, ion separation to ion detection. A preferential transmission of heavier isotopes can be considered as major cause of instrumental isotopic fractionation between nuclides [44]. In ICP-MS, the ionization source and the interface are believed to play a major role in IIF, mainly due to the large pressure drop between the ion source and the expansion region.…”

“…With the objective to calibrate a mass spectrometer for the effect of mass discrimination, a number of different strategies have been proposed over the years, of which a few have developed as frequently applied approaches for isotope amount ratio analysis. Details can be retrieved from [16,44,45].…”