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Abstract  

C, N, O, F and P can be analyzed by instrumental photon activation analysis (IPAA) including decay curve analysis. The interference of 30P (T 1/2 = 149.9 s) by 15O (T 1/2 = 122.2 s) can be ruled out by direct positron measurement making use of the largely different maximum β+-energies of both nuclides (3.24 MeV and 1.73 MeV, respectively). Interference by carbon (11C) can be avoided by sub-threshold activation with 17 MeV bremsstrahlung. The short half-life of 30P allows a high productivity of the method. Reliability was demonstrated in the range of 0.2%–2% P (detection limit = 40 μg/g). Analysis of a certified reference material (BCR-CRM 063) yielded excellent agreement with the certified data.

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Abstract  

An analytical procedure was developed to determine the concentration of some elements regarded as trace impurities in nuclear fuel using inductively coupled plasma mass spectrometry (ICPMS) associated to the matrix matching method. The assessment of this approach was carried out using a set of certified reference materials produced by the New Brunswick Laboratory (NBL). Eighteen out of the twenty-four elements in the reference materials could be easily determined. It was found that the mean values for reproducibility and accuracy were 5.0% and 15.0%. The remaining six elements provided mean values of 11.0% and 37.0%, respectively. They could not be adequately determined due to the effects of analyte signal suppression and spectral interference.

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Abstract  

Multielement determinations in the certified reference materials of soils (IAEA soil-5 and 7) have been studied fundamentally by instrumental photon activation analysis using the internal standard method coupled with the standard addition method. For the soil-5 sample, in the first place, the qualities of the comparative standards prepared by two processing methods were compared with each other. As a result, it was demonstrated that a highly accurate and precise multielement determination can be achieved easily by minor improvement in the processing method of the comparative standard to ensure homogeneity. The utility of this processing method for soil samples was proved further through a similar analysis in another soil sample (IAEA soil-7).

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Journal of Radioanalytical and Nuclear Chemistry
Authors: C. Chéry, S. Herremans, V. Van Lierde, F. Vanhaecke, M. Freitas, and R. Jasekera

Abstract  

Spices were analyzed by ICP-MS for determination of the ultra-micro trace elements in the human adult, Bi, Cd, Co, Ni, Pd, Pt, Se, Sn, Te, Tl, to complement previous results obtained by INAA and by EDXRF. The spices, originating from Sri Lanka, were curry, chilli powder and turmeric powders, coriander, cinnamon, black pepper, fennel, rampeh and curry leaves, and cumin. The analytical procedure was validated by analyzing the certified reference materials NIST SRM 1572 Citrus Leaves and NIST SRM 1573 Tomato Leaves. The results indicate that spices may contribute well to the daily optimal uptake of nutrients of a human adult. The adequacy of spices as a reference material with certified ultra micro trace elements is suggested.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: J. Sterba, M. Blaauw, G. Steinhauser, M. Bichler, F. Grass, and G. Westphal

Abstract  

Combining the powers of a fast pneumatic transport system and the Automatic Activation Analyzer (AAA) of the Atominstitut in Vienna with the newest version of the IAEA k 0-Software, the application of the k 0-method to the determination of short-lived radionuclides becomes easily possible. By calculating Asp-values with the IAEA software, the often expensive and time-consuming measurement of Asp-values using certified reference materials is reduced to quality control checks. Measurements clearly show that the two approaches are equivalent, especially since both take self-absorption and neutron self-shielding into account. In this way it is possible to expand the library of the AAA with many hitherto unobtainable Asp-values. At the same time, using highly accurate Asp-values already measured for many short-lived radionuclides, k 0-values for those can be produced with a simple procedure.

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Abstract  

Several bioanalytical techniques have been employed in conjunction with instrumental neutron activation analysis (INAA) to study metalloproteins and protein-bound trace elements in bovine kidneys. The accuracy of the INAA method developed has been evaluated by analyzing certified reference materials. Up to 29 elements can be reliably determined in biological tissue samples by INAA. Dialysis of the bovine kidney homogenate shows that more than 90% of Ca, Cd, Cu, Fe, Mg, Mn, Mo, Se, V and Zn, and about 20% of Br are bound to macromolecules, mainly proteins. A combination of gel filtration and ion exchange chromatography, chromatofocusing, electrofocusing, ammonium sulphate precipitation and INAA of the bovine kidney microsomecytosol subcellular fraction further indicates that much of the copper is associated with a single protein of an isoelectric point around 5 and a molecular weight of about 30 000 daltons. Some results on manganese proteins are also reported.

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Abstract  

A series of measurements were carried out to establish the reliability associated with isotope ratio (235/238) measurements on uranium samples using a quadrupole inductively coupled plasma mass spectrometer (ICPMS). Figures of merit related to the isotopic measurements were determined using non certified as well as certified materials provided by the New Brunswick Laboratory (NBL). The experimental results showed that repeatability is around 0.5% while reproducibility was calculated as 0.27%. Mass discrimination was determined as 0.03% per mass unit and the system linearity check over five orders of isotope ratios yielded a mass discrimination factor (K factor) of 1.0002±0.0081 (0.81%, 2s). The mean error of measurement obtained from six different certified reference materials was 0.77%.

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Simple and rapid analytical procedures for the AAS (Atomic Absorption Spectrometry) determination of Zn, Cd, Ni, Mo and Pb in biological, geological and soil samples are described. Special attention was paid to sample preparation, which is the step, most vulnerable to contaminants. Optimal conditions are presented for the wet digestion of plant matrices, products and waste for the coal treatment and soil matrices with different acids including: nitric, perchloric, hydrochloric, hydrofluoric, sulfuric and hydrogen peroxide along with optimal temperature programmes for subsequent electrothermal (ET)-AAS and flame (F)-AAS determination of Zn, Cd, Ni, Mo and Pb. Results of the analysis of all samples are discussed. The proposed method allows obviating the organic matrix (soil and plant) destruction stage, shortening the analyte dissolution time, reducing cost, and minimizing hazards of loss and contamination. The validity and versatility of the methods developed were verified by the analysis of certified reference materials.

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Abstract  

The accuracy and precision of the results obtained for total mercury in various environmental and biological samples and certified reference materials (CRMs) by various analytical methods, including k 0-instrumental neutron activation analysis (k 0-INAA), radiochemical neutron activation analysis (RNAA) and cold vapour atomic absorption (and atomic fluorescence) spectrometry (CVAAS/AFS) used in routine analysis in our laboratory, were investigated. Three natural matrix reference materials (RMs) from the International Atomic Energy Agency (IAEA), five CRMs from the Institute for Reference Materials and Measurements (IRMM), six CRMs from the National Institute of Standards and Technology (NIST) and one from the Jožef Stefan Institute (IJS) were analyzed. The results obtained show good agreement between certified or assigned values, and between the methods used, except for some data obtained by k 0-INAA in biological samples. This can be explained by losses during irradiation in semi-open systems (irradiation in plastic ampoules) and/or spectral interferences.

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Abstract  

A rapid and simple sample preparation method for plutonium determination in environmental samples by inductively coupled plasma sector field mass spectrometry (ICP-SFMS) and alpha-spectrometry is described. The developed procedure involves a selective CaF2 co-precipitation for preconcentration followed by extraction chromatographic separation. The proposed method effectively eliminates the possible interferences in mass spectrometric analysis and also removes interfering radionuclides that may disturb alpha-spectrometric measurement. For 239Pu, 240Pu and 241Pu limits of detection of 9.0 fg·g−1 (0.021 mBq), 1.7 fg·g−1 (0.014 mBq) and 3.1 fg·g−1 (11.9 mBq) were achieved by ICP-SFMS, respectively, and 0.02 mBq by alpha-spectrometry. Results of certified reference materials agreed well with the recommended values.

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