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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  

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  

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  

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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Summary  

Instrumental neutron activation analysis (INAA) was applied to determine the inorganic composition of leaves and extracts from three different species of Casearia genus plant (C. sylvestris, C. decandra and C. obliqua). Statistical analysis of the analytical data of leaf showed that the three Casearia species present similar elemental composition. Extract from C. sylvestris showed significantly different inorganic content in comparison with the two other species. Certified reference material NIST SRM-1515 Apple Leaves was analyzed for quality control.

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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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Abstract  

Essential and non-essential elements in the parts (leaves, fruits) of several kinds of herbal tea and camomile marked in Italy were determined by polarised X rays fluorescence spectrometer (EDPXRF). The quality of data was assured by calibrating the instrument with certified reference materials. The elements are found to be present in different plants in various proportions depending to soil composition and the climate in which the plant grows.

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