Authors:S. Bürger, K. Mathew, P. Mason, and U. Narayanan
The characterized concentrations of 24 impurity elements in New Brunswick Laboratory (NBL) Certified Reference Material (CRM)
124 were reevaluated. A provisional certificate of analysis was issued in September 1983 based upon the “as prepared” values
(gravimetric mixing). The provisional certificate does not state uncertainties for the characterized values, or estimate the
degree of homogeneity. Since release of the provisional certificate of analysis various laboratories have reported analytical
results for CRM 124. Based upon the reported data a re-evaluation of the characterized values with an estimate of their uncertainties
was performed in this work. An assessment of the degree of homogeneity was included. The overall difference between the re-evaluated
values for the 24 impurity elements and the “as prepared” values from the provisional certificate of analysis is negligible
compared to the uncertainties. Therefore, NBL will establish the “as prepared” values as the certified values and use the
derived uncertainties from this work for the uncertainties of the certified values. The traceability of the “as prepared”
values was established by the gravimetric mixing procedure employed during the preparation of the CRM. NBL further recommends
a minimum sample size of 1 g of the CRM material to ensure homogeneity. Samples should be dried by heating up to 110 °C for
one hour before use.
Authors:L. De Carlan, D. Franck, P. Beaujard, P. Burger, B. Cahan, O. Maillard, C. Mazur, P. Pihet, and R. Soulié
Although much progress was made by using high purity gemanium detectors for direct measurement of239Pu in man, the improvement of lung spectroscopy sensitivity remains a challenge. Previous work showed that passivated implanted planar silicon detectors could provide an alternative by combining high-energy resolution at room temperature and planar geometry with large detection arrays. This paper reports on the status of this research based on the characterisation of 3×3 cm2 and 6×3 cm2 strip silicon detectors. Furthemore, the possibility to apply such detectors towards other monitoring problems for accidental situations such as the direct measurement of small contaminated surfaces was investigated.
Authors:K. Mathew, S. Bürger, S. Vogt, P. Mason, M. Morales-Arteaga, and U. Narayanan
The International Organization for Standardization (ISO) Guide to the expression of Uncertainty in Measurement (GUM) was developed
to meet the demand for a standardized way of evaluating and expressing uncertainties. The Davies and Gray (D&G) titrimetry
method is routinely used in nuclear safeguards for uranium accountability measurement and a statement of the uncertainty that
can reasonably be attributed to the measured assay value is therefore of importance. A mathematical model for an uncertainty
evaluation of D&G measurements in compliance with ISO GUM is presented. This is illustrated by a numerical example and the
utilization of the uncertainty budget is explored.
Authors:L. Červinka, P. Burg, I. Soural, V. Mašán, A. Čížková, J. Souček, V. Višacki, O. Ponjičan, and A. Sedlar
Sauvignon Blanc represents an important grape variety. The wine made from this variety is known to have a wide range of aroma profiles from nettles to tropical fruits. Beside the raw material quality (grapes), the quality of wines can be fundamentally influenced by the technological conditions applied in the wine making process. Yeast and other microorganisms play a key role in the formation of metabolites during alcoholic fermentation. In this study, the effects of autochthonous or selected wine yeasts (Saccharomyces cerevisiae) and fermentation temperatures (15 °C and 19 °C) were tested on major monoterpenes contents of wines during the period 2016–2017. The obtained values show that the highest contents of linalool (24.36 μg L−1) and hotrienol (11.84 μg L−1) were determined in wine samples produced with active (selected) wine yeast at lower temperature. Sensory evaluation results indicated that monoterpenes can have a positive effect on the overall sensory quality of Sauvignon Blanc wines, despite the fact that their determined concentrations in the evaluated samples were not higher than their threshold values.