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Abstract  

As a part of the Iraqi Food Analysis Programme /I.F.A.P./ the concentration of Na, Mg, P, Cl, K, Ca, Zn, Se, Br, Rb and I in natural milk collected from different regions of Iraq, and in milk powder samples have been determined by using the NAA technique. It was found that except for the elements I, Rb and Br the concentration of the elements was approximately identical in both the natural milks and milk powders.

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Abstract  

Characterizations of three major parameters of Certified Reference Materials (CRMs) concentration values of multielements, homogeneities of multielements, and stabilities of the materials, were further studied by NAA. In the determinations of multielements in RMs, both relative and K0 (and its extension) standardizations were used in an effort to detect hidden systematic errors and expand the number of determinable elements. In the evaluations of multielemental homogeneities, double sampling constants as well as Ingamells' Ks and F-test were used to establish semi-quantitative expressions of sampling uncertainty vs. size and number of subsamples for given elements in given materials. For the investigation of the stabilities of certified values, K0 NAA is to be used in follow-up analyses to test variations of certified values and provide updated and/or newly determined data. The final goal is to make NAA a definitive method for multi-trace element certification, a reliable method for homogeneity characterization, and a reproducible method for stability test. Examples are given to show preliminary results on the above aspects.

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Abstract  

The Br (0.0022 ± 0.0006 gL−1), Ca (0.113 ± 0.012 gL−1), Cl (3.07 ± 0.36 gL−1), K (2.63 ± 0.14 gL−1), Mg (0.045 ± 0.002 gL−1) and Na (2.09 ± 0.10 gL−1) concentrations were determined in whole blood of SJL/J mice using the Neutron Activation Analysis (NAA) technique. Eleven whole blood samples were analyzed in the IEA-R1 nuclear reactor at IPEN (São Paulo, Brazil). These data contribute for applications in veterinary medicine related to biochemistry analyses using whole blood. Moreover, the correlation with human blood estimation allows to checking the similarities for studying muscular dystrophy using this model animal.

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Abstract  

Thirty two elements were determined in five pieces of presumed cosmic dust samples with the weights of 5 to 25 g by neutron activation analysis (NAA). All the interferences from fission, threshold reactions and -spectra were corrected for and different counting geometries normalized. Enrichment factors with reference to C1-chondrite are about 200 and 100 for lithophile refractory elements (e.g., V, Th, Hf and W) and rare earth elements (REE), respectively. Deficiencies were observed for Co, Cr, Mg and Na, etc. The C1-chondrite normalized REE patterns are close to those of extraterrestrial materials, with no anomaly of Eu, indicating an extraterrestrial origin of the grain samples analyzed.

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Abstract  

Five copper alloys were prepared with modern powder metallurgical processes in the frame of the European project Improvement of Means of Measurement on Archaeological Copper-Alloys for Characterisation and Conservation (IMMACO) and certified for As, Pb, Sn and Zn mass fractions. Similar in their composition to archaeological bronze alloys, these Certified Reference Materials (CRMs) are to be used for calibration of XRF instruments for characterization of archaeological samples either in the laboratory or in the field. This paper presents and compares the successful contribution of our non-destructive analytical methods (k 0-NAA and PIXE) to the IMMACO project and to the certification of the five reference materials.

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Abstract  

Background soils from areas around the United States Department of Energy facilities in Oak Ridge, Tennessee were characterized as part of an environmental restoration project. The data obtained in this project were validated using guidelines from the Environmental Protection Agency (EPA) Contract Laboratory Program (CLP), when EPA methods were used. However, there are no final EPA guidelines for validation of data obtained using radiochemical analytical methods, so procedures for validation had to be developed. This paper will describe the validation guidelines that were developed for neutron activation analysis (NAA) data and discuss the regulatory basis for them.

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Summary  

A simple pre-irradiation separation approach has been worked out for the determination of traces of tellurium in high purity selenium followed by neutron activation analysis (NAA) for the end determination of the analyte/s. The difference in volatilities of these elements has been utilized for the separation of the analyte from the matrix. The complete volatility of selenium at ~600 °C was established using neutron activation analysis and selenium radiotracer. Standard addition was used to validate the results. The proposed method of separation of selenium prior to irradiation could make the determination of tellurium possible and also improved the detection limit by several folds.

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Abstract  

Mn-nodule is one of the most important deep sea mineral resources to be explored and exploited in the next century. Analytical quality control based on this kind of Certified Reference Materials (CRMs) is therefore necessay. In the present work, nearly 30 elements in two Chinese Mn nodule Reference Materials (RMs), GSPN-2 and GSPN-3, were determined using extendedK 0-relative comparison NAA technique, developed in our laboratory. The unique features of this work include; (1) high accuracy obtained by the interal validation function of our technique; (2) extensive determinable elements obtained by the hybrid nature of our software and (3) neutron flux self-shielding corrections.

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Abstract  

In this study the neutron activation analysis (NAA) technique was applied to determine Ca and Mg in whole blood from inhabitants of Brazil for the purpose of establishing concentration ranges indicative of sex and age. The initiative to perform these measurements is related to the increase in heart disease. According to recent statistics from WHO, the average is one death due to heart attack in Brazil, every five minutes. The measures were performed considering lifestyle factors (non-smokers, non-drinkers and no history of toxicological exposure) of Brazilian inhabitants. A healthy group constituted of male (n = 94) and female (n = 84) blood donors, ages between 18 and 70 years and above 50 kg, was selected from the blood banks and hematological laboratories of Brazil. The influence of sex was also investigated considering several age ranges (18–29, 30–40, 41–50, >50 years). The results show significant differences when a comparison is made by sex and age and may be useful to identify or prevent clinical diseases. These results emphasize the need to perform periodic evaluation of Ca and Mg in blood.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: Donghui Huang, Caijin Xiao, Bangfa Ni, Weizhi Tian, Yuanxun Zhang, Pingsheng Wang, CunXiong Liu, Guiying Zhang, Hongchao Sun, Haiqing Zhang, and Changjun Zhao

Abstract  

Taking advantages of nuclear analytical techniques (NATs) with non-destruction, multielement capability, small and estimable uncertainties over a wide range of sample sizes, the sampling behavior of multielements for a home-made natural matrix material was studied with sample sizes ranging from several hundred mg down to tenths ng, namely nine orders of magnitude, by a combination of three NATs, neutron activation analysis (NAA), proton induced X-ray emission (PIXE) and synchrotron radiation X-ray flurescence (SR-XRF), in an effort to explore a procedure for the development of certified reference materials (CRMs) suitable for quality control of microanalysis. For accurately weighable sample sizes (>1 mg), sampling uncertainties for 13 elements were found to be less than 1% by INAA. For sample sizes unable to be accurately weighed (<1 mg), PIXE and SR-XRF were used, respectively. Sampling uncertainties were found to be less than 1% at sample sizes of tenth mg level for seven elements, and less than 10% on ng levels for three elements. Considering these three elements have satisfied homogeneity (sampling uncertainty less than 10%) at ng sample size level, any one of them can be served as a “relative balance” in sampling behavior characterization of multielements on sample size levels larger than ng (e.g., μg level). On this basis, sampling uncertainties for nine elements were found to be less than 10% on μg sample size level by INAA. The results indicate that the matrix is eligible as a candidate of CRMs suitable for quality control of solid sampling microanalysis.

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