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1.
B. Hołyńska Mariusz Olko Beata Ostachowicz Jerzy Ostachowicz Dariusz Węgrzynek Martine Claes Rene Van Grieken Pieter de Bokx Peter Kump Marijan Necemer 《Analytical and bioanalytical chemistry》1998,362(3):294-298
An intercomparison survey has been carried out in order to evaluate the performance of two related X-ray fluorescence techniques as compared to the achievements of several other analytical techniques applied for trace elements determination in drinking water. A relatively new technique, total reflection X-ray fluorescence (TXRF) and a novel related technique, grazing emission X-ray fluorescence (GEXRF) have been used for the analysis of a mineral water sample. The concentrations of the following elements have been determined: Na, Mg, K, Ca, Ni, Cu, Zn and Sr. The mineral water sample has also been analyzed by a number of other analytical techniques, routinely utilized in drinking water quality control. The analyses were performed in eleven laboratories which reported 286 individual determinations producing 75 laboratory means. From the obtained results, it can be concluded that the TXRF technique is suitable for a direct determination of heavy elements in drinking water (above potassium, Z = 19). This technique can compete with other analytical techniques routinely used in water quality monitoring. First results obtained with GEXRF spectrometry show that this technique can be successfully applied for the determination of low-Z elements in drinking water. However, results for sodium and magnesium were systematically too low, indicating that modifications of the quantification procedure may be required to improve the accuracy of determination for these light elements. 相似文献
2.
B. Hoyska Mariusz Olko Beata Ostachowicz Jerzy Ostachowicz Dariusz Wgrzynek Martine Claes Rene Van Grieken Pieter de Bokx Peter Kump Marijan Necemer 《Fresenius' Journal of Analytical Chemistry》1998,362(3):294-298
An intercomparison survey has been carried out in order to evaluate the performance of two related X-ray fluorescence techniques
as compared to the achievements of several other analytical techniques applied for trace elements determination in drinking
water. A relatively new technique, total reflection X-ray fluorescence (TXRF) and a novel related technique, grazing emission
X-ray fluorescence (GEXRF) have been used for the analysis of a mineral water sample. The concentrations of the following
elements have been determined: Na, Mg, K, Ca, Ni, Cu, Zn and Sr. The mineral water sample has also been analyzed by a number
of other analytical techniques, routinely utilized in drinking water quality control. The analyses were performed in eleven
laboratories which reported 286 individual determinations producing 75 laboratory means. From the obtained results, it can
be concluded that the TXRF technique is suitable for a direct determination of heavy elements in drinking water (above potassium,
Z = 19). This technique can compete with other analytical techniques routinely used in water quality monitoring. First results
obtained with GEXRF spectrometry show that this technique can be successfully applied for the determination of low-Z elements
in drinking water. However, results for sodium and magnesium were systematically too low, indicating that modifications of
the quantification procedure may be required to improve the accuracy of determination for these light elements.
Received: 5 January 1998 / Revised: 17 February 1998 / Accepted: 18 February 1998 相似文献
3.
S. Melsom 《Journal of Radioanalytical and Nuclear Chemistry》1970,4(2):355-363
Some of the rare earth elements have been determined in U.S.G.S. Standard Rocks W1 and G2 using instrumental neutron activation
analysis with a Ge(Li) detector. The experimental conditions were chosen to investigate the precision and accuracy to be expected
when using the method for routine purposes.
The results are compared with data obtained after chemical group separation of the rare earths and with data reported by other
workers; the agreement is, in general, good.
La, Ce, Nd, Sm, Eu, Tb, Yb, Lu and Se were determined with the instrumental method and, after group separation, data were
obtained for Gd, Dy, Ho and Tm in addition.
It is concluded that the accuracy of the data obtained with the non-destructive method is, in general, as good as the precision
for each element. 相似文献
4.
E. Cortes 《Journal of Radioanalytical and Nuclear Chemistry》1984,84(1):157-164
Instrumental neutron activation analysis of eight geochemical standard materials has been carried-out and the concentration values of nine rare-earth elements (REE) (La, Ce, Nd, Sm, Eu, Gd, Tb, Yb and Lu) have been determined. Discussion of some problems in the determination of those elements is presented and the results obtained are compared with literature values. In general, good agreement with available data was obtained but discrepancies with concentration values for a number of elements in some of these standards are discussed. 相似文献
5.
The determination of thirteen elements, eleven rare-earth elements (La, Ce, Nd, Sm, Eu, Gd, Tb, Ho, Tm, Tb and Lu), thorium and uranium were performed by instrumental neutron activation analysis for four geological reference materials (G-2, AGV-1, GSP-1 and SY-2) as well as our laboratory rare-earth standard. The analyses were performed using a low energy photon detector coupled to an Apple IIe microprocessor employed as a multichannel analyzer not only to collect the data but also for data analysis. Finally, based on this work we have proposed a simple, rapid routine method for the determination of eleven rare-earth elements, thorium and uranium in geological materials employing IVIC's RV-1 nuclear reactor. 相似文献
6.
K. Shiraishi 《Journal of Radioanalytical and Nuclear Chemistry》1998,238(1-2):67-73
Fifteen radionuclides and stable elements in 18 food groups, which have been obtained by a market basket method, were determined
by semiquantitative ICP-MS. Strontium, Cs,232Th, and238U were also determined by quantitative analytical ICP-MS or ICP-AES. For Sr,232Th, and238U, results of the semi-quantitative ICP-MS and the quantitative approaches were found to be in a good agreement, within ±10%.
The other eleven elements (Li, V, Cr, Mn, Co, Ni, Cu, Rb, Mo, Cd, and Ba were determined with in 30% errors at the sub-ppb
(ng/ml) level. More elements could be measured by the semi-quantitative mode if concentrations were at least at the sub-ppb
level. 相似文献
7.
Tetsuya Ashino Kan-ichi Makabe Kunio Takada 《Analytical and bioanalytical chemistry》1994,349(10-11):772-774
The elements in lithium potassium niobate and lithium niobate containing vanadium (such as aluminum, lithium, niobium, potassium and vanadium) were determined by inductively coupled plasma atomic emission spectrometry after fusion of the sample with ammonium hydrogensulfate. The samples were completely decomposed and high precision results were obtained for the metallic elements. Oxygen has been determined by a helium carrier fusion thermal conductivity method using both a nickel capsule and tin as a melting flux in a graphite crucible. 相似文献
8.
Improvements in the specifications of low-energy, intrinsic Ge detectors have enabled the routine determination of the concentrations
in geological samples of eleven rare earth elements, including lanthanum, without using a Ge(Li) detector. The efficiency
of an intrinsic Ge detector is compared with a high-efficiency Ge(Li) detector, and a quantitative assessment of the effect
of X-ray and gamma-ray interferences is given. Rare earth element abundances in four U. S. G. S. standard rocks have been
determined. 相似文献
9.
Fifteen elements at trace levels have been determined by neutron activation analysis in the biological standard kale distributed
byBowen. La, Br, As, Se, Sc, Ag, Zn, Co, Cr, Sb, Eu, Fe, and Zr have been determined by a nondestructive technique using a high-resolution
Ge(Li) detector. Two more elements, Au and Hg, have been determined after radiochemical separation. The nondestructive procedure
is shown to yield data in generally good agreement with those obtained by destructive techniques. Potential sources of error
in the nondestructive technique are discussed. 相似文献
10.
K. M. Barfoot I. V. Mitchell H. L. Eschbach P. I. Mason W. B. Gilboy 《Journal of Radioanalytical and Nuclear Chemistry》1979,53(1-2):255-271
Particle-induced X-ray emission (PIXE) analysis of the lighter elements in time-resolved air particulate deposits has been
carried out. Minimum detection limits have been determined for 1.0, 2.0 and 3.5 MeVprotons. Quantitative PIXE analysis results,
obtained with 2 MeV protons, are given for temporal variations in the elemental concentrations of Na, Al, Si, S, Cl, K, Ca
and Fe. Rutherford backscattering (RBS) spectra were taken simultaneously with the PIXE spectra to provide information on
lead concentrations and deposit thicknesses. The experimental problems associated with the quantitative analysis of light
elements on cellulose acetate filters are described. The relationship between these results and meteorological data is discussed. 相似文献
11.
P. Krause B. Erbslöh R. Niedergesäß R. Pepelnik A. Prange 《Fresenius' Journal of Analytical Chemistry》1995,353(1):3-11
The suitability of four different digestion procedures, i.e. i.) an aqua regia digestion according to DIN 38 414-S7, ii.) a pressure digestion using HNO3/HF in PTFE-vessels, iii.) a HNO3/HF + HCl-pressure digestion in PTFE-vessels and iv.) a HNO3/HF + HCl-pressure digestion using microwave induction, has been evaluated with regard to the quantitative determination of about 50 elements in environmental samples. Three sediments of the river Elbe and two standard reference materials (MESS-1 and NIST 1645) have been employed. The analytical results from the dissolved samples, obtained using inductively coupled plasma mass- and optical emission spectrometry as well as total reflection X-ray fluorescence spectrometry, have been compared with those obtained by instrumental neutron activation analysis. Only digestion procedures using HNO3/HF with a subsequent evaporation to dryness and dissolution in HCl have led to appropriate results for a wide range of elements (more than 50 elements in total). Because of its low contamination risk and its time saving, the microwave digestion is preferred. For this digestion procedure the accordance among the different instrumental methods used is high (better than 15% deviation) in general. A few elements (16) could be determined quantitatively only by a single method. 相似文献
12.
《Spectrochimica Acta Part B: Atomic Spectroscopy》1996,51(1):127-137
Post ablation ionization (PAI) of neutral atoms from a low alloy steel has been investigated using non-resonant laser ionization in a time-of-flight mass spectrometer. By varying the delay between the ablation and ionization lasers, the velocity distributions of the Ti, V, Cr, Mn and Fe atoms have been determined simultaneously. These distributions have been recorded as a function of ablation laser fluence. The half-range Maxwell-Boltzmann velocity distribution has been used to fit the data and different characteristic temperatures have been determined for the various elements in the sample. The quantitative capability of this method for bulk and surface analysis has been evaluated by calculating the relative sensitivity factors (RSFs) for the various constituent elements. The RSFs for all of the elements are seen to be highly dependent on the delay between the ablating and ionizing lasers. This dependence was reduced by integrating the temporal dependent ion yield, leading to a significant improvement in the calculated RSF values. It was also found that the RSFs were not highly dependent on the power density of the ablation laser beam. 相似文献
13.
A new method using Monte Carlo source simulation of interference reactions in neutron activation analysis experiments has been developed. The neutron spectrum at the sample location has been simulated using the Monte Carlo code MCNP and the contributions of different elements to produce a specified gamma line have been determined. The produced response matrix has been used to measure peak areas and the sample masses of the elements of interest. A number of benchmark experiments have been performed and the calculated results verified against known values. The good agreement obtained between the calculated and known values suggests that this technique may be useful for the elimination of interference reactions in neutron activation analysis. 相似文献
14.
《Spectrochimica Acta Part B: Atomic Spectroscopy》2001,56(11):2107-2115
A one-step sample preparation by electro-deposition for total-reflection X-ray fluorescence (TXRF) analysis has been developed using a common three-electrode arrangement with a rotating disc as the working electrode. Several elements such as Cr, Mn, Fe, Co, Ni, Cu, Zn, Ag, Cd, Pb, As and U have been determined simultaneously in saline matrix. A special electrode tip has been constructed as a holder for the TXRF sample carrier, which consists of polished glassy carbon. The influence of parameters such as time, pH value, and trace element concentration on the deposition yield has been examined for 14 elements. From repeatability studies, the uncertainty in deposition yields at the 95% confidence level has been found to be less than 20% for most of these elements. Typical detection limits range from 5 to 20 ng/l under the experimental conditions applied here. By an appropriate choice of the reference element and by calculation of yield factors, reliable quantification can be achieved directly by internal standardization. First results obtained for the standard reference material CRM 505 are presented. 相似文献
15.
A double-focusing Glow Discharge Mass Spectrometer (GDMS) installed in a glovebox for nuclear sample screening has been employed for isotopic measurements. Isotopic compositions of zirconium, silicon, lithium, boron, uranium and plutonium which are elements of nuclear concern have been determined. Interferences arising from the matrix sample and the discharge gas (Ar) for each of these elements are discussed. The GDMS results are compared with those from Thermal Ionization Mass Spectrometry (TIMS). For boron and lithium at microg/g-ng/g levels, the two methods gave results in good agreement. In samples containing uranium the isotopic composition obtained by GDMS was in agreement with those from TIMS independently of the enrichment. Attempts for the determination of plutonium isotopic composition were also made. In this case, due to the interferences of uranium at mass 238 and americium at mass 241, the GDMS raw data are complementary with those values obtained from physical non-destructive techniques. 相似文献
16.
S. Waheed N. Siddique A. Rahman S. Saeed J. H. Zaidi S. Ahmad 《Journal of Radioanalytical and Nuclear Chemistry》2004,262(3):691-696
Instrumental neutron activation analysis (INAA) and electro-thermal atomic absorption spectrometry (ETAAS) were employed to determine the toxic elements in fourteen fruits harvested in Pakistan. As, Br, Hg, Sb and Se were determined using INAA. Cadmium and Pb were determined using ETAAS. The intake levels of all toxic elements have been calculated. The data show that dates supply the maximum amount of most of the toxic elements. Peels of apple and pear have also been investigated and were found to contain higher concentration of toxic elements than their edible parts. The reliability of the techniques has been established by the use of standard reference materials. This study shows that all investigated fruits cultivated and consumed in Pakistan are safe for human consumption. 相似文献
17.
Instrumental neutron activation analysis (INAA) and electro-thermal atomic absorption spectrometry (ETAAS) were employed to determine the toxic elements in fourteen fruits harvested in Pakistan. As, Br, Hg, Sb and Se were determined using INAA. Cadmium and Pb were determined using ETAAS. The intake levels of all toxic elements have been calculated. The data show that dates supply the maximum amount of most of the toxic elements. Peels of apple and pear have also been investigated and were found to contain higher concentration of toxic elements than their edible parts. The reliability of the techniques has been established by the use of standard reference materials. This study shows that all investigated fruits cultivated and consumed in Pakistan are safe for human consumption. 相似文献
18.
Toussaint B Chedin M Vincent U Bordin G Rodriguez AR 《Journal of chromatography. A》2005,1088(1-2):40-48
A recently in-house validated method for the liquid chromatography-tandem mass spectrometry (LC-MS/MS) determination of eleven (fluoro)quinolone antibiotics (FQs) in pig kidney has been fully validated through an intercomparison exercise. This ring trial involved eight European laboratories and was based on the Commission Decision 2002/657/CE for validation of method and on the IUPAC protocol for method-performances studies. The laboratories data were submitted to a one-way analysis of variance. Satisfactory results were obtained for each FQ with regards to within- and between-laboratory reproducibility and accuracy. The method was validated for the simultaneous qualitative and quantitative determination of the eleven FQs in pig kidney around their maximum residue limit (MRL) as defined in the European Council Regulation 2377/90/EEC. 相似文献
19.
A comparison has been made between the results of the matrix-ion species ratio (MISR) method for quantification of secondary-ion mass-spectrometry data and spark-source mass-spectrometry analysis using photoplate detection for analysis of the steel basis of AlZn coated wire products. For SIMS quantification a suitable set of sensitivity factors, corrected for the actual surface sampling condition, was used. The results of both methods compare well. The SIMS results were, for most elements, within 25% of the concentration determined by SSMS. This could indicate that reasonably accurate results can be obtained by using the matrix-ion species ratio method for SIMS. 相似文献
20.
Jeran Z Jaćimović R Batic F Smodis B Wolterbeek HT 《Analytical and bioanalytical chemistry》1996,354(5-6):681-687
In 1992, a monitoring survey has been started on the national scale in Slovenia using the epiphytic lichen Hypogymnia physodes (L.) Nyl. The primary aim has been to analyse lichens using the k(0)-based INAA method to obtain information about the levels of elements in the atmosphere and to identify significant pollution sources. Monte Carlo-Assisted Factor Analysis was applied to a data set of the 28 elements As, Ag, Ba, Br, Ce, Cd, Co, Cr, Cs, Fe, Ga, Hf, Hg, K, La, Mo, Na, Rb, Sb, Sc, Se, Sr, Sm, Tb, Th, U, W and Zn, which have been selected from the elements determined as the most important ones for the identification of pollution sources. A Monte Carlo approach has been used to give more insight into the uncertainties and significance levels of the factor analysis results. It has been found that concentration patterns in lichens yielded 9 factors (source types) which are presented and discussed in detail. The geographical patterns of the contributions of all factors are also shown. 相似文献