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Abstract  

The paper describes the collection and preparation of a second generation biological reference material (human blood serum) with trace element levels closely approximating those in real human blood plasma or serum samples.

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Abstract  

Reference materials are necessary to improve or to maintain a high quality of analysis. To avoid bias as far as possible, the BCR certifies reference materials on the basis of results of different methods used by different laboratories. A proper selection of good methods and laboratories makes it possible to obtain excellent agreement and narrow confidence intervals. Neutron activation techniques are suited for many key elements; their results are in good agreement with those of other techniques.

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Abstract  

In order to develop new reference materials for microanalytical nuclear techniques, the Scanning Proton Microprobe (SPM) technique was used to determine homogeneity levels within 100×200 m2 micro-area on small pieces of IAEA Urban Dust reference materials. The experimental methods are described in detail. The results show that IAEA-396A/M Vienna Urban Dust is homogeneous enough for a SRM (10% for Si, S, K, Ca, Fe, Cu, Zn) for small sample analysis.

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Abstract  

Reference materials for the speciation and quantification of chromium in contaminated soils were prepared by impregnating diatomaceous earth with BaCrO4 and Cr2O3. The chronium concentrations of these materials were confirmed to be 200 mg/kg both by atomic absorption spectrometry and by instrumental neutron activation analysis, but monthly assays over two calendar quarters of the reference material impregnated with BaCrO4 revealed the hexavalent chromium was not stable in this matrix.

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Abstract  

A routine procedure for monostandard INAA using short-lived radionuclides with half-lives from 2 min to 15 hrs is described. Ten elements (Al, Mg, Ti, V, Mn, Cl, Na, K. Br and Cu) are determined in Chinese Biological Standard Reference Material (peach leaves). The quality of analysis was checked by analyzing the U. S. NBS Standard Reference Materials SRM-1571 and SRM-1648.

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Abstract  

The concentration of99Tc in IAEA reference materials has been determined with an ICP-MS as 0.86±0.07 Bq·kg−1 dry for IAEA-373 (grass) and 0.25±0.02 Bq·kg−1 dry for IAEA-375 (soil). These being sufficiently higher than the detection limits of typical measurement methods, both materials can be used as reference materials for determining low-level99Tc in environmental samples.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: R. Jakopič, A. Verbruggen, R. Eykens, F. Kehoe, H. Kühn, Y. Kushigeta, U. Jacobsson, J. Bauwens, S. Richter, R. Wellum, and Y. Aregbe

Abstract  

In nuclear safeguards, precise and accurate isotopic analyses are needed for two major elements from the nuclear fuel cycle: uranium and plutonium. This can be achieved by Isotope Dilution Mass Spectrometry (IDMS), which is one of the most reliable analytical techniques for the determination of plutonium amount content to a high level of accuracy. In order to achieve reliable isotope measurements isotopic reference materials with certified amount of plutonium and isotopic composition are required. At the Institute for Reference Materials and Measurements (IRMM) various plutonium spike reference materials for isotopes 239Pu, 240Pu, 242Pu and 244Pu are available. This enabled the setup of an inter-calibration campaign inter-linking selected plutonium spikes on a metrological basis applying state-of-the-art measurement procedures. The aim of this campaign is threefold: firstly to perform measurements on selected plutonium spike isotopic reference materials for quality control purposes, secondly to verify the amount content and the isotopic composition of the recently produced IRMM-1027m large sized dried (LSD) spikes and thirdly to demonstrate IRMM’s measurement capabilities for plutonium analysis via external quality tools. The obtained results using various spike isotopic reference materials will be presented and discussed in this paper. The measurement uncertainties of the IDMS results were calculated according to the guide to the expression of uncertainty in measurement (GUM).

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Abstract  

The k0-standardization method of INAA (instrumental neutron activation analysis) was applied to three reference materials: NIST (National Institute for Standards and Technology, Washington, D.C., USA) SRM (Standard Reference Material) 1646 Estuarine Sediment, NIST SRM 2704 Buffalo River Sediment and IAEA (International Atomic Energy Agency) CRM (Certified Reference Material) SL-1 Lake Sediment. Among the 50 elements sought yielding long-lived radioisotopes after (n, ) activation, for 32 elements numerical values were obtained, and for the remaining 18, only detection limits were estimated. When comparing the results obtained in this work to certified, recommended or other literature values, good agreement was found, proving that the same analytical procedure can be applied with confidence for analysis of environmental sediment samples.

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Abstract  

Trace amounts of transition elements (Co, Cr, Cu, Fe, Mn and V) and other seven elements in optical waveguide samples were determined by INAA. The contents of impurities in ultra-pure materials are less than those of high-purity materials and of G.R. grade. The increase of contamination of trace transition elements and iridium from furnace or crucible are observed in the production of optical glass fibers. Up to seventeen elements were determined in five NBS biological standard reference materials: Oyster Tissue: SRM-1566, Brewers Yeast: SRM-1569, Spinach: SRM-1570, Orchard Leaves: SRM-1571 and Tuna Fish, and in four Japanese biological standard reference materials: Tea Leaves B&C, Pepperbush and Shark Meat. The analytical results in NBS and Japanese standard reference materials are in good agreement with published values and certified values by NBS.

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Abstract  

Instrumental neutron activation analysis (INAA) has been employed in the investigation of mass balance for mercury species analysis in the analytical process. A new human hair reference material (IAEA-085) was analyzed for methylmercury using a solid/liquid extraction procedure, with samples of extracts, residues, and untreated samples being analyzed by INAA. The certified reference material NIES CRM No. 13, human hair, was analyzed in parallel. From the results obtained through the mass balance studies, it was found that the extraction procedure was quantitatively complete, and that there was no difference between the mass balance of Hg and the total Hg in the untreated materials.

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