Development of SI Traceable Standards for Element Determination

In Germany a system of primary amount of substance standards for elemental analysis is being developed, which forms the material's basis for the National Standards for element determination. The metrological concept and technical approach is briefly described. The objective of traceability in chemistry, in this case for elemental determination, is illustrated on the example of copper

Evaluation of different calibration strategies for the analysis of pure copper and zinc samples using femtosecond laser ablation ICP-MS

Solution-doped metal powder pellets as well as aspirated liquids were used as calibration samples to analyze pure copper and zinc certified reference materials (CRMs) by femtosecond laser ablation ICP-MS. It was demonstrated that calibration by copper pellets resulted in relative deviations up to 20%, whereas fs-LA-ICP-MS among copper-based CRMs led to inaccuracies in the same range unless nominal mass fractions were chosen to be <3mg/kg. Calibration by zinc pellets generally provided better accuracy. Depending on the analyte considered, deviations below 10% were obtained even for mass fractions close to the limit of quantification. Our data, therefore, indicate solution-doped metal powder pellets to be suitable as calibration samples for fs-LA-ICP-MS of metals. Furthermore, the utilization of liquid standards for calibration was found to result in stronger deviations of up to 50% for both copper and zinc samples which, in addition, turned out to be dependent on the plasma conditions. Figure Different calibration strategies for fs-LA-ICP-M

Thermodynamic (p, ρ, T) characterization of a reference high-calorific natural gas mixture when hydrogen is added up to 20 % (mol/mol)

The injection of hydrogen into the natural-gas grid is an alternative during the process of a gradual decarbonization of the heat and power supply. When dealing with hydrogen-enriched natural gas mixtures, the performance of the reference equations of state habitually used for natural gas should be validated by using high-precision experimental thermophysical data from multicomponent reference mixtures prepared with the lowest possible uncertainty in composition. In this work, we present experimental density data for an 11-compound high-calorific (hydrogen-free) natural gas mixture and for two derived hydrogen-enriched natural gas mixtures prepared by adding (10 and 20) mol-% of hydrogen to the original standard natural gas mixture. The three mixtures were prepared gravimetrically according to ISO 6142–1 for maximum precision in their composition and thus qualify for reference materials. A single-sinker densimeter was used to determine the density of the mixtures from (250–350) K and up to 20 MPa. The experimental density results of this work have been compared to the densities calculated by three different reference equations of state for natural gas related mixtures: the AGA8-DC92 EoS, the GERG-2008 EoS, and an improved version of the GERG-2008 EoS. While relative deviations of the experimental density data for the hydrogen-free natural gas mixture are always within the claimed uncertainty of the three considered equations of state, larger deviations can be observed for the hydrogen-enriched natural gas mixtures from any of the three equations of state, especially for the lowest temperature and the highest pressures.his work was funded by the European Metrology Programme on Innovation and Research (EMPIR), Funder ID: 10.13039/100014132, Grant No. 19ENG03 MefHySto, and by the Regional Government of Castilla y León (Junta de Castilla y León), the Ministry of Science and Innovation MCIN, and the European Union NextGenerationEU/PRTR, project C17.I01.P01.S21

Determination of Main and Minor Components of Silicon Based Materials by a Combustion with Elemental Fluorine, Separation of Gaseous Fluorination Products by a Carrier Gas Distillation and Gas Mass Spectrometry.

Abstract not availableJRC.D-Institute for Reference Materials and Measurements (Geel

Special new techniques of atomic spectrometric methods for trace analysis of high purity metals

How spectral interferences of analyte ions with polyatomic ions containing matrix atoms can be identified, reduced or eliminated was demonstrated for different pure metals using a double focussing ICP mass spectrometer in higher mass resolution. An in-situ coating procedure of the nickel inlet cones of the ICP mass spectrometer with a thin quartz glass film was developed in our laboratory. It leads to a drastic decrease of memory effects and blanks, especially for the analytes Na, Ni and Li. The limits of determination (LODs) of these analytes were decreased for more than one order of magnitude. The analytical performance of two atomic spectrometric techniques combined with electrothermal vaporization (ETV) of metallic microsamples was investigated using tungsten as an example. An ICP optical emission spectrometer equipped with ETV (ETV ICP OES) as well as a solid sampling atomic absorption spectrometer (SS-ET AAS) were used. Benefits and drawbacks of both method combinations were summarized and compared. The multielement capability of ETV ICP OES was much higher than the of SS-ET AAS. LODs of the less refractory analytes were lower with SS-ET AAS than with ETV ICP OES

Conversion of Carbon into CH4 for SI-Traceable Measurements of Absolute Carbon Isotope Amount. Ratios: A Feasibility Study.

Abstract not availableJRC.D-Institute for Reference Materials and Measurements (Geel

Calibration of Isotopic Measurements.

Abstract not availableJRC.D-Institute for Reference Materials and Measurements (Geel

The Preparation of two Synthetic Isotope Mixtures for the Calibration of Isotope Amount Ratio Measurements of Sulfur.

Abstract not availableJRC.D-Institute for Reference Materials and Measurements (Geel