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1.
2.
The concentrations of major (Na, K, Ca, Mg), minor (Cu, Fe) and trace (Li, Sr, Ba) elements in untreated, undiluted human body fluids (serum, urine, saliva, cerebrospinal fiuid) are determined. The sample volume is 110 μl. Micro-standard addition procedures and manual background correction are used to minimize matrix interferences. The RSD ranged from 3.1. to 8.6%. Accuracy was evaluated with NIES Candidate Reference Material freeze-dried human serum and NBS SRM-2670 freeze-dried urine.  相似文献   

3.
Trace amounts of transition elements (Co, Cr, Cu, Fe, Mn and V) and other seven elements in optical waveguide samples were determined by INAA. The contents of impurities in ultra-pure materials are less than those of high-purity materials and of G.R. grade. The increase of contamination of trace transition elements and iridium from furnace or crucible are observed in the production of optical glass fibers. Up to seventeen elements were determined in five NBS biological standard reference materials: Oyster Tissue: SRM-1566, Brewers Yeast: SRM-1569, Spinach: SRM-1570, Orchard Leaves: SRM-1571 and Tuna Fish, and in four Japanese biological standard reference materials: Tea Leaves B&C, Pepperbush and Shark Meat. The analytical results in NBS and Japanese standard reference materials are in good agreement with published values and certified values by NBS.  相似文献   

4.
The method of k0 standardization is suitable for routine multi-element determinations by reactor neutron activation. Investigation of NBS steel standards showed the systematic error of the method to be less than 3%. Numerical evaluation of the spectra was found to be fast and convenient. Fourteen elements in the steel samples were determined; for nine, the standard deviation was less than 4%. Thirty seven elements were determined in NBS SRM-1663a Coal Fly Ash; agreement with certified values was again very good.  相似文献   

5.
A procedure for monostandard INAA of 21 elements (Hg, As, Br, Cr, Sb, Se, Ba, Zn, Ca, Ce, Co, Cs, Eu, Fe, Hf, K, La, Rb, Sc, Sr, Ta) in Chinese Biological Standard Reference Material (peach leaves) is described. The accuracy of the procedure was checked by analyzing the U.S. NBS Standard Reference Materials SRM-1571 and SRM-1632a.  相似文献   

6.
The determination of trace elements in the various stages of the water cycle is very important. Economic procedures for multi-element determinations of trace elements in various matrices are needed. The applications of total-reflection x-ray fluorescence spectrometry in this general area are reviewed briefly, with examples relating to rain, river and sea waters, sediments, particulate matter and manganese nodules and crusts, as well as mussel tissue. Up to 25 elements can be determined; these are S, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, As, Pb, Se, Rb, Sr, Y, Zr, Mo, Ag, Cd, Sb and Ba. Preliminary treatments of the various matrices are described. Accuracy checks by analysis of reference standards and by application of independent techniques are reported.  相似文献   

7.
Major and trace elements (Na, Mg, Al, Si, P, K, Ca, Ti, Mn, Fe, Rb, Sr, Y, Zr, La, Ce, Pr, Nd, Sm, Gd, Dy, Th and U) in igneous rocks were assayed with fused lithium borate glass beads using X-ray fluorescence spectrometry. Low dilution glass beads, which had a 1:1 sample-to-flux ratio, were prepared for determination of rare earth elements. Complete vitrification of 1:1 mixture required heating twice at 1200 degrees C with agitation. Extra pure reagents containing determinants were used for calibrating standards instead of the rock standard. The calibration curves of the 23 elements showed good linearity. Furthermore, the lower limits of detection corresponding to three times the standard deviation for blank measurements were 26 mass ppm for Na2O, 6.7 for MgO, 4.5 for Al2O3, 4.5 for SiO2, 18 for P2O5, 1.1 for K2O, 4.0 for CaO, 3.9 for TiO2, 1.6 for MnO, 0.8 for Fe2O3, 0.5 for Rb, 0.2 for Sr, 0.4 for Y, 0.5 for Zr, 3.3 for La, 6.5 for Ce, 2.7 for Pr, 2.1 for Nd, 1.7 for Sm, 0.7 for Gd, 2.7 for Dy, 0.5 for Th, and 0.6 for U. Using the present method, we determined the contents of these 23 elements in four rhyolitic and granitic rocks from Japan.  相似文献   

8.
Tar sands from a deep borehole in southwestern Nigeria were subjected to elemental analysis by simultaneous proton induced X-ray emission (PIXE) and proton induced gamma-ray emission (PIGME) techniques. The concentration of 22 major, minor and trace elements, namely Al, Ca, Cr, Cu, F, Fe, Ga, Ge, K, Li, Mg, Mn, Na, P, Pb, Rb, S, Si, Sr, Ti, Zn and Zr were determined. The accuracy and precision of the techniques for chemical analysis were assured by analysing the NBS 278 geological standard.  相似文献   

9.
    
Zusammenfassung Die Röntgenfluorescenzanalyse von Staubproben mit Cd-109 als Strahlenquelle wird beschrieben. Für die Eichung des Verfahrens werden Kieselgelstandards verwendet. Die Korrektur der Matrixeffekte erfolgt mit Hilfe der Compton-Streupeaks. In den Staubproben werden neben den Elementen K, Ca, Ti, Fe, Rb, Sr, Y, Zr, die als natürliche Bestandteile des Bodens anzusehen sind, die Elemente Cr, Mn, Ni, Cu, Zn, Br und Pb nachgewiesen.
Determination of trace elements in dust samples by X-ray fluorescence analysis with radionuclide excitation, with special regard to matrix effects
The analysis of dust samples by X-ray fluorescence using Cd-109 as X-ray source is described. For calibration silica gel standards are used. The correction for matrix effects is carried out by means of the Compton peaks. Besides the elements K, Ca, Ti, Fe, Rb, Sr, Y, Zr, which may be considered to be natural components of the ground, the elements Cr, Mn, Ni, Cu, Zn, Br and Pb are determined in the dust samples.
  相似文献   

10.
Concentrations of 35 elements in Chinese Standard Rocks (GSR-1 to GSR-3) and Soils (GSS-1 to GSS-8) have been measured with INAA using the SLOWPOKE reactor. At the same time, the U. S. NBS reference standards: SRM-1632a (Bituminous Coal), SRM-1633a (Coal Fly Ash) and SRM-1646 (Estuarine Sediment) were also analyzed in order to cross-check the accuracy of this method. The results obtained indicate that the reproducibility of the method is satisfactory for most of the elements, namely the precision in general, is better than ±10%. Comparison of our values for NBS SRM-1632a, 1633a and 1646 with the certified values of NBS or with values cited in the literature indicates good agreement. The results were found to be accurate within ±10% error of the established results.  相似文献   

11.
Substoichiometric extraction of chromium with tetraphenylarsonium chloride (TPACl), tri-n-octylamine (TNOA), diethylammonium diethyldithiocarbamate (DDDC) and ammonium pyrrolidinedithiocarbamate (APDC) was examined in detail. Chromium can be extracted substoichiometrically in a pH range, which is 1.1–2.6 for the TPACl compound, 0.6–2.3 for the TNOA compound, 5.1–6.4 for the DDCC chelate and 3.9–4.9 for the APDC chelate. Chromium in high-purity calcium carbonate, Orchard Leaves (NBS SRM-1571) and Brewers Yeast (NBS SRM-1569) was determined by neutron activation analysis combined with substoichiometric extraction by DDDC and APDC. The values of 2.0±0.02 ppm and 2.6±0.2 ppm were obtained for Brewers Yeast and Orchard Leaves, respectively. These values were in good agreement with the values reported by NBS. The reaction mechanism and the reaction ratio between hexavalent chromium and dithiocarbamate were also discussed.  相似文献   

12.
Minor and trace elements composition of bottom sediments from water bodies in Western Paraguay have been investigated by XRF techniques to determine their correlation as well as provenance. The analysis of complex spectra was performed by the AXIL software and the quantitative analysis by the QAES software. Analyzed trace elements were the refractory elements Rb, Sr, Y, Zr, Nb, Ba, La, Ce, Pr, Nd, Zr, y and other HFSE as Cr, Ni, Cu, together with Zn. Minor elements were Ti, Mn, Fe which are often to the above refractories related. According to their normalized spidergrams two sets of sediments can be differentiated. Those from Pilcomayo and Verde rivers as well as from km164-Wetland show light rare earth elements (LREE) enrichment, negative Nb and Ti anomalies and no spike at Zr. On the other hand, sediments from Confuso, Aguaray(Jehe), Negro and Montelindo rivers have spidergrams very alike, with strong negative anomalies at Nb, Nd and Ti whereas a positive at Zr. Further, in the former there is a strong correlation of Fe versus the refractory elements; such a correlation does not exist in the latter. The sediments from the Pilcomayo & Verde Rivers and from the km164-Wetland evolved as the sub-Andean/Andean metamorphic/sedimentary materials.  相似文献   

13.
An empirical study has been made of the potential of high energy γ photon activation and high resolution γ-ray spectrometry for the survey analysis of trace elements in a variety of materials. Human blood, urine, bone ash, standard glass (NBS, SRM 612) and air particulates, along with synthetic multi-element standards, have been studied following irradiation with γ photons of maximum energy 17–45 MeV. Elements found to be suited to determination by γ activation include Sb, As, Bi, Cd, Cs, Ca, Ce, Cr, Fe, Au, Pb, Mg, Mo, Ni, Nb, Rb, Sr, Tl, Ti, Tm, Zn and Zr. γ spectra, elemental concentrations measured, and/or limits of detection observed, for the matrices studied are given.  相似文献   

14.
Mankind still depend on traditional herbal medicine for the treatment of various diseases and ailments. This paper discusses the elemental composition and concentration of medicinal plants investigated by energy dispersive X-ray fluorescence. The elements present in medicinal plants are P, Cl, K, Ca, S, Al, Ti, V, Rb, Sr, Zr, Nb, Mo, In, Sn, I and Ce. The physical basis of the used analytical method, the experimental set up and the procedure of sample preparation are presented. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

15.
Samples of soil, plant material and water collected on the Croatian island Krk in northern Adriatic sea were analyzed for a number of elements (Ca, Ti, Mn, Fe, Ni, Cu, Zn, As, Br, Rb, Sr, Zr, Pb) by using energy dispersive X-ray fluorescence (EDXRF) as an analytical tool. Some of these data have been previously used to produce geochemical map of the island.1 In addition, trace element contents of hair from children, attending elementary and secondary schools, has been investigated using the same analytical method for Mg, S, Ca, Cr, Mn, Fe, Ni, Cu, Zn, As, Hg and Pb elements. Concentrations of the twelve elements and nine variables from the questionnaire, i.e., age, sex, living place, transportation, medication, hair colour, hair type, type of shampoo used and hair treatment, were considered in the statistical analysis. The observed differences for the seven island's communes have also been discussed. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

16.
(Simultaneous determination of trace elements in high-purity chromium by inductively-coupled plasma/atomic emission spectrometry after matrix separation.) The production of high-purity metals requires routine determinations of elements in the ng g?1 range. Procedures based on wet chemical separation of matrix and trace elements followed by inductively-coupled plasma/atomic emission spectrometry are suitable. The separation of 19 trace metals (Be, Bi, Ca, Cd, Co, Cu, Fe, La, Mg, Mn, Nb, Ni, Pb, Ta, Ti, Th, U, Zn and Zr) from high-purity chromium powder is described. The powder is dissolved in hydrochloric acid and oxidized with perchloric acid or alkaline hydrogen peroxide, and the trace elements are precipitated at pH 11–13 and collected on cellulose loaded with indium hydroxide or on cellulose-Hyphan. The detection limits of the total procedure vary from 10 ng g?1 for cadmium to 600 ng g?1 for zinc.  相似文献   

17.
Khiem  L. H.  Sera  K.  Hosokawa  T.  Quyet  N. H.  Frontasyeva  M. V.  Trinh  T. T. M.  My  N. T. B.  Nghia  N. T.  Trung  T. D.  Nam  L. D.  Hong  K. T.  Mai  N. N.  Thang  D. V.  Son  N. A.  Thanh  T. T.  Tien  D. P. T. 《Journal of Radioanalytical and Nuclear Chemistry》2020,324(1):43-54
Journal of Radioanalytical and Nuclear Chemistry - The concentration of 22 metal elements including Mg, Al, Si, P, S, Cl, K, Ca, Ti, Cr, Mn, Fe, Ni, Cu, Zn, As, Br, Rb, Sr, Zr, Ba and Pb in Barbula...  相似文献   

18.
Sastri VS  Chakrabarti CL  Willis DE 《Talanta》1969,16(7):1093-1098
Studies on the mutual chemical interferences in the atomic-absorption spectroscopy of Ca, Mg, Ba, Sr, Ti, Zr, Hf, Fe, as simple salts and metallocenes, show that the results can be interpreted in terms of formation of mixed oxides of two elements, non-volatility of the mixed oxide compound, and the crystal structure of the mixed oxide compound.  相似文献   

19.
A scheme for INAA of 32 elements (As, Au, Ba, Br, Ca, Cd, Ce, Co, Cr, Cs, Eu, Fe, Hf, Hg, Ir, K, La, Lu, Mn, Na, Nd, Rb, Sb, Sc, Sm, Ta, Tb, Th, U, W. Yb, Zn) in quartz glass is proposed. The accuracy of the procedure is evaluated by the analysis of two NBS standard reference materials (SRM-1571 and SRM-1632-a). The method is convenient for routine work. The method was used for the determination of impurities in laboratory quartz glass. Dedicated to the 60th birthday of acad. prof. g. bliznakov  相似文献   

20.
Freitas MC  Martinho E 《Talanta》1989,36(4):527-531
Instrumental neutron activation analysis was applied to four reference materials: NBS 1573 (Tomato Leaves), NBS 1645 (Citrus Leaves), NBS 1645 (River Sediment), and IAEA MA-A-2 (TM) (Fish Flesh). The k(0)-standardization method was used. The results are compared with (i) reference values (mostly non-certified) and (ii) published values obtained by other methods. Good agreement is found for most of the elements. For some elements, large discrepancies are observed.  相似文献   

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