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Abstract  

This was a very well attended meeting with the numbers reflecting an increasing world-wide demand for certified reference materials. This is an inevitable consequence of the growth of schemes for the accreditation of the quality of measurement.

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Acta Chromatographica
Authors: Young Sang Kwon, Sung-Gil Choi, Seung-Min Lee, Jong-Hwan Kim, and Jong-Su Seo

PCDD/Fs (EPA 1613 CS1 to CS5, LCS, and ISS) were certified purchases from Wellington Laboratories Inc. (Guelph, Ontario, Canada) and were used for the development of the analytical methodology. Certified reference material (CRM) samples including BCR

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Abstract  

Aluminosilicate clay samples were analyzed for the constituent elements with respect to a certified reference material using microcrystalline cellulose powder as a binder for presentation as a pressed pellet to an energy dispersive X-ray fluorescence spectrometer. Sample preparation for presentation is highlighted. The data manipulation to achieve the analytical accuracy from the inherent precision is discussed.

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Abstract  

A simple and rapid method was developed for the determination of selenium in human serum using a pre-irradiation separation technique of ultrafiltration followed by neutron activation analysis via the short-lived activation product77mSe. The method was validated using certified reference material.

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Abstract  

Black spruce /Picea mariana/ twigs and needles have been collected from a uraniferous area of northern Saskatchewan and characterized for their content of some radionuclides and trace elements in an interlaboratory program. These materials, rich in uranium, are available as reference materials, for estimating accuracy in the analysis of vegetation, from the Canadian Certified Reference Materials Project in Ottawa, Canada.

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Abstract  

The conditions for the determination of Co, Cr, Fe, Mn, Ni and Pb in plant materials and As, Ba, Fe, Pb, Sr, Rb and Zr in soils by energy dispersive X-ray fluorescence analysis with americium-241 as excitation source are discussed. The applicability of the proposed method is tested by the analysis of certified reference materials and of two plant biomonitors.

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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  

This work is focused at the demonstration of the overall adequacy of the procedures introduced in a Brazilian laboratory for conducting the k 0-standardized NAA. Concentrations of 29 elements determined in certified reference materials of plants and geological matrices are evaluated. Most of the experimentally determined values agreed well with the reference data and no consistent bias could be attributed to the analytical system adopted.

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Abstract  

Instrumental neutron activation analysis (INAA) was applied to assess trace element concentrations in six samples of aspirin tablets acquired in São Paulo city, Brazil. Concentrations of the elements Br, Ca, Co, Cr, Fe, K, La, Na, Sc and Zn were determined. Comparisons were made between the results obtained with published data for aspirins from foreign countries. Certified reference materials, INCT-MPH-2 Mixed Polish Herbs were analyzed for quality control of the analytical results.

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Abstract  

Instrumental neutron activation analysis (INAA) was applied to determine Ca, Cl, Mg, Mn, Na, Sr and Zn in human dentin and enamel tissues from carious and sound teeth. Comparisons were made between the results obtained in carious and sound dental tissues for dentin and enamel. The findings obtained were also compared with the published data. Accuracy and precision of the results were evaluated by analyzing certified reference material.

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