Performance and robustness of a multi-user, multi-spectrometer system for INAA

Abstract

The laboratory for instrumental neutron activation analysis at the Reactor Institute Delft, Delft University of Technology uses a network of 3 gamma-ray spectrometers with well-type detectors and 2 gamma-ray spectrometers with coaxial detectors, all equipped with modern sample changers, as well as 2 spectrometers with coaxial detectors at the two fast rabbit systems. A wide variety of samples is processed through the system, all at specific optimized (and thus different) analytical protocols, and using different combination of the spectrometer systems. The gamma-ray spectra are analyzed by several qualified operators. The laboratory therefore needs to anticipate on the occurrence of random and systematic inconsistencies in the results (such as bias, non-linearity or wrong assignments due to spectral interferences) resulting from differences in operator performance, selection of analytical protocol and experimental conditions. This has been accomplished by taking advantage of the systematic processing of internal quality control samples such as certified reference materials and blanks in each test run. The data from these internal quality control analyses have been stored in a databank since 1991, and are now used to assess the various method performance indicators as indicators for the method’s robustness.

Trace element measurement for assessment of dog food safety

“…A neutron flux monitor, obtained by pipetting a zinc standard solution in a filter paper was added to each sample, and counted separately. Mass fraction results and their expanded uncertainties (k=2) were obtained by kZn method, using the Apollo software, with a validated procedure (Bode and Blaauw 2012).…”

Chromium Exposure and Risk of Cardiovascular Disease in High Cardiovascular Risk Subjects ― Nested Case-Control Study in the Prevention With Mediterranean Diet (PREDIMED) Study ―

“…A precise description of the analytical methodology has been published elsewhere. 17, 18 Cr was detected in all samples. The detection limit for a sample of average weight (65 mg) was 0.12 μg/g, and it varied between 0.04 μg/g (sample mass, 250 mg) and 6.56 μg/g (sample mass, 0.53 mg).…”

The Influence of Plasma-Based Nitriding and Oxidizing Treatments on the Mechanical and Corrosion Properties of CoCrMo Biomedical Alloy

“…The quality management system fulfills the requirements of the NEN-EN-ISO/IEC 17025:2005. [39] III. RESULTS A. Nitrided, Oxidized, and Double-Treated Samples…”