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Journal of Radioanalytical and Nuclear Chemistry
Authors: W. Kwiatek, B. Kubica, R. Gryboś, M. Krośniak, E. Dutkiewicz and R. Hajduk

Abstract  

Proton induced X-ray emission (PIXE) and atomic absorption spectroscopy (AAS) were used for vanadium determination in animal tissues. The vanadium concentration levels were determined in blood, kidneys and livers taken from rats. Two groups of the animals were treated with different diets. The diet for the first group was supplemented with vanadium compounds while the diet for the second one was assumed to be a normal diet. The second group was treated as control. In order to achieve the best minimum detectable limit (MDL)1 the samples were subject to a special sample preparation procedure. Blood and kidneys were mineralized with an APDC compound. The mineralization process was performed according to the procedure described previously.2 The application of PIXE3 is very useful for different types of samples. PIXE measurements were performed with a proton beam at the Institute of Nuclear Physics in Cracow, Poland while the AAS measurements were done at the Institute of Molecular Biology, Jagiellonian University, Poland. The concentration levels of vanadium in blood and kidneys are compared and discussed. There were no significant statistical differences between results of vanadium concentration levels determined by the abovementioned techniques. The PIXE technique had the advantage over the AAS technique of giving a broad spectrum of trace elements analyzed in a single measurement. Therefore with the help of sample preparation procedure the application of the PIXE method seems to be suitable for such analyzes.

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Journal of Thermal Analysis and Calorimetry
Authors: C. Dagounaki, K. Chrissafis, A. Kassoli-Fournaraki, A. Tsirambides, C. Sikalidis and K. Paraskevopoulos

Abstract  

Representative carbonate rock samples collected from the broader area of Kozani (NW Macedonia, Greece) are examined. The participation of constituents in the formations was determined combining three different methods of analysis, atomic absorption spectroscopy (AAS), X-ray diffraction analysis (XRD) and thermogravimetry (TG). The three methods are used in a complimentary way in order to specify the exact composition of the samples. Although the question about the composition can be answered by AAS, the percentage of the included calcite and dolomite can be determined with accuracy, only through TG analysis, under the appropriate conditions, regarding the gas carrier. The results of the analysis lead to a more complete view of the geological conditions that predominated in the studied area.

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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  

A simple abrasion procedure for the determination of the distribution of a radiotracer as a function of depth in solid flat aliquots is presented. Application to the concentration distribution in graphite furnaces for flameless AAS is possible down to 0.1 m.

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Abstract  

The fundamental parameters method (FPM) for X-ray fluorescence (XRF) has been applied to determine the MN, Cr and Sr components of aluminium wires and sheets. The results are compared with neutron activation analysis (NAA) and atomic absorption spectrometry (AAS). The FPM does not require standards, however, it requires the spectra of the pure element for the concentration determination.

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Abstract  

Two types of gas-liquid separators for use in on-line hydride generation AAS have been examined: the classical one, in which gas and liquid are separated by gravity and that based on diffusion through a pemeable tube. Results are presented for the determination of arsenic species (arsenite, As(III); arsenate, As(V); monomethylarsonic acid, MMAA; dimethylarsinic acid, DMAA). Yield (of hydride generation and gas-liquid separation) and response time are investigated as functions of the experimental variables. It is concluded that in conjunction with a cold trap, only the classical gas-liquid separator is satisfactory.

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Abstract  

For the first time the moss biomonitoring technique has been applied to air pollution monitoring in Central Russia (Tula region). INAA at the IBR-2 reactor has made it possible to determine the content of 33 elements in mosses collected at 83 sampling site. In addition to NAA, flame AAS (atomic absorption spectrometry) was applied to determine the content of Cd, Cu and Pb. Factor analysis was applied to determine possible sources of trace element deposition in Tula mosses. The geographical distribution of factor scores and some element distribution maps over the investigated territory are presented.

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Abstract  

Trace and toxic elements in Certified Reference Material (CRM) made of Korean rice at the Korea Research Institute of Standards and Science have been analyzed by Instrumental Neutron Activation Analysis (INAA). Data intercomparison from the measurement with those of Atomic Absorption Spectrometry (AAS) and Induced Coupled Plasma Spectrometry (ICPS) has been studied. The powdered samples were sterilized at 1.5·106 rad in the bottles using a60Co source after sieving and spiking to specific elements such as As, Cd, Cr, Cu and Hg and then the homogeneity of samples was assessed. Rice flour (SRM 1568a) and standard solutions made by the National Institute of Standards Technology (NIST) were used to construct the calibration curves for the INAA and the chemical methods, respectively. The uncertainties and concentration of constituent elements were determined and the possibility of their use for analytical quality control was considered.

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Abstract  

Lead stocks of wooden-lead anchors found along the Bulgarian Black Sea coast and typologically dated VI c. B.C.-III c. A. D. have been analyzed for chemical composition and lead isotope ratios by INAA, AAS and mass spectrometry. Using multivariate methods for analysis as well as simple bivariate plots the lead for production of the stocks was localized as originating from Laurion, Thassos, Troas, Chalkidike and the Rhodopes. In general, the chemical composition is not recommended to be used for provenance study of lead artefacts. Combining the results from this study with the existing typological classification certain conclusions about the production and distribution of lead anchors in the Aegean region are made.

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Acta Alimentaria
Authors: N. Adányi, M. Váradi, I. Sziklai-László, P. Snyder, R. D. Snyder and M. Á. Cser

Total daily Se intake was determined by duplicate diet collection, venous blood samples were taken and urine was collected over 24 h in order to measure selenium input and output in healthy, American and Hungarian children aged 8 to 17 living in Budapest. The American children consumed not only locally processed food. Food samples were weighed, mixed, homogenised and the Se content was determined by Instrumental neutron activation analysis (INAA). The Se concentration of blood, plasma and urine samples was determined by atomic absorption spectrometry-hydride generation (AAS-HG) after wet digestion.  Se intake calculated for wet weight was 62±18.5 mg/day in American children. In the Hungarian children the mean Se intake was about 35% less than in the Americans. Se concentrations in plasma were 0.84±0.16, in whole blood 1.13±0.17 mmol l-1 in the Americans, higher than those in healthy Hungarian children (0.64±0.10 and 0.83±0.12 mmol l-1, respectively) of similar age and gender. Urinary Se output calculated for creatinin was higher in the children from abroad (27.0±9.5 mg Se/day/g creatinin) compared to Hungarians (11.0±5.0 mg Se/day/g creatinin).

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