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1.
The IAEA-331 spinach material NIST SRM 1570a Spinach Leaves, submitted to an intercomparison run by the IAEA, has been analysed by k0-based INAA with counting using both low and high energy photon detectors. The results have been compared with (i) the certified values of the NIST SRM 1570a; the agreement is good, taking into account the uncertainties; and (ii) the certified and consensus values of the former NIST SRM 1570 Spinach Leaves, their composition in minor and trace-elements are quite similar; however a lower content has been observed for Co, Fe and Sc in the IAEA-331 and for Zn in the SRM 1570. For quality control, the NIST 1573 Tomato Leaves and the NIST 1575 Pine Needles have been analysed using the same conditions as for the IAEA-331. The results agree quite well with the certified and consensus values given in the literature.  相似文献   

2.
The objective of this study was to evaluate the influence of mining activity on elemental concentrations in kale grown around a mining area. Two sites studied are in the Iron Quadrangle, Minas Gerais, Brazil, considered one of the richest mineral-bearing regions in the world. One site is near mineral exploration activity and the other is an ecological area. A comparator site outside the Iron Quadrangle was also analyzed. This work focused on the determination of the elemental concentrations in kale applying the k0-instrumental neutron activation analysis. As the Brazilian legislation specifies values for soil only, the results for kale were compared to the literature values and it was found that the vegetable does not present any health risks.  相似文献   

3.
Summary The Iron Quadrangle, Minas Gerais, Brazil, is rich in mineral occurrences and is considered one of the richest mineral-bearing regions in the world. Most investigations in this region have dealt with the determination of arsenic and mercury but so far few studies have been carried out aiming at determining other important elements. Having in mind the potential risk caused by mineral activities, this study was developed in order to assess the potential influence of the soil on foodstuffs. The soil samples were collected from three sites inside and outside the Iron Quadrangle. The samples were analyzed at the Laboratory for Neutron Activation Analysis, CDTN/CNEN by the k0-instrumental neutron activation analysis. This paper reports the elemental concentration determined in soil and emphasises the elements cited in the Brazilian environmental legislation for soil. This work also confirms the high elemental concentration of several minerals, however, it is difficult to distinguish the contamination from anthropogenic activities from the natural occurrence.  相似文献   

4.
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   

5.
The objective of this work was to compare the results obtained by the relative INAA and k 0-INAA methods for the same input parameters (sample mass, nuclear data, net peak area for the same gamma line and the same measurement and same cooling and measurement times). In total eight environmental soil and sediment reference materials (RM) or certified reference materials (CRM) from different producers were analysed. In this work only the recommended or certified values were considered, allowing comparison of the two methods for 30 elements. The results point out that k 0-INAA possesses superior qualities compared to relative INAA, being insensitive to flux gradients, and independent of recommended/certified values in RMs/CRMs, often used as standards in relative INAA.  相似文献   

6.
Two samples of Napoleon's hair were received for determination of arsenic, mercury and other trace elements by INAA. Before sample irradiation, the hairs were washed following the IAEA washing procedure. Two standard reference materials of GBW09101 (human hair) and NIST/SRM1572 (citrus leaves) were analyzed along with Napoleon's hair for quality control. Standardization was conducted by applying the k 0-method implemented in the program MULTINAA. The contents of arsenic and mercury as well as three additional elements chromium, antimony and zinc in Napoleon's hair are reported. Compared to the present normal levels, all of the determined elements in Napoleon's hair, except the mercury, are found to be irregular.  相似文献   

7.
Mass and elemental concentrations in PM10 and PM2.5 — airborne particulate matter with an aerodynamic diameter below 10 μm and 2.5 μm, respectively — have been evaluated in mainland Portugal since 1993. The data herein refer to areas generally impacted by emissions from electrical power plants, either coal- or oil-fired, which are mostly large, state-of-the-art facilities. Background areas have been sampled as well, and results from one of them are given for comparison. Through the country, lead levels are well below the European enacted values, particularly since unleaded fuels became mandatory in the late 1990s. Nickel appears especially concentrated in PM2.5 and, apart from extreme cases (rural sites, coal-fired plants), its levels are not significantly different from place to place. Highest values for arsenic and mercury have been found in the vicinity of the coal-fired plants. Cadmium data, if only available for metropolitan Lisbon, seems to confirm the trend for anthropogenic elements appearing mainly in fine particulates.  相似文献   

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10.
Neutron spectrum correction has been attempted for the k0-factors of the non-1/v elements which are affected neutron spectrum difference. Effective g-factors and Westcott g-factors, which are neutron spectrum correction factors obtained from an actual neutron spectrum and the Maxwellian distribution, respectively, for the non-1/v elements were calculated using their neutron cross section data of JENDEL-3.2. The neutron spectrum correction was made for the measured k0-factors of the non-1/v elements such as Cd, Sm and Gd with the cold and thermal guided neutron beams of JRR-3M using the g-factors. The corrected k0-factors between the cold and thermal neutron beams using both g-factors for both neutron beams agreed well for Cd. However, 9 to 44% deviations have been found for Sm and Gd, respectively.  相似文献   

11.
Summary ko-Based Neutron Activation Analysis (koINAA) was used to analyze the candidate reference materials Apple Leaves and Peach Leaves, and Oriental Tobacco Leaves and Virginia Tobacco Leaves. Concentration values for 27 elements were measured. The accuracy was ascertained by analysis of two certified reference materials, NIST 1572 Citrus Leaves and 1573 Tomato Leaves. The homogeneity test of the IAEA Evernia prunastri candidate reference material in aliquots 100 mg is extended to the elements Sc, Cr, Fe, Co, Zn, Rb, Sb, Cs, Ba, Ce and Th.  相似文献   

12.
A facility for neutron capture prompt gamma-ray activation analysis, installed on a curved thermal neutron guide at the ILL High Flux Reactor, is described. Elemental sensitivities for B, Sm and Gd have been measured. The performance of the facility has been assessed by the measurement of these trace elements in eleven USGS geochemical reference samples and comparison of the results with existing values. Preliminary concentrations of B, Sm and Gd are also reported for twelve French GRS.  相似文献   

13.
As a part of the food analysis program executed at Es-Salam research reactor by neutron activation analysis laboratory, the concentration of As, Ba, Br, Ca, Fe, K, La, Rb and Zn in baby formulas milk have been determined by using INAA and k 0-NAA techniques. It was found that the concentration of all elements obtained by both techniques was relatively identical for the three brands of the 0–6 and 6–12 months of analyzed samples. In addition, the analytical results have been compared with those given by producers.  相似文献   

14.
Trace elements in natural drugs determined by INAA   总被引:1,自引:0,他引:1  
Natural drugs are widely used for diuretic, phlegm elimination and stomach invigoration purposes. Seventy-five of the most common remedies used by Chinese people have been subjected to trace element survey analysis by instrumental neutron activition. Within this large number of different natural products, fourteen trace elements (K, Sc, Cr, Fe, Co, Zn, Br, Rb, Cs, La, Sm, Eu, Au and Th) are commonly detected. Among these elements, Fe had the highes: concentration followed by Zn, and Rb, Sm, Eu and Au were found to have the lowest concentations. Although the three groups of natural drugs exhibit a widely different therapeutic action, the concentration ranges of the fourteen elements were very similar. While this suggests no apparent specific role for the trace elements in the drug function, parallels are drawn between the known drug related functions of Rb, Zn, Br, Fe, Co and K and the levels of elements found in the natural drugs. It is concluded that the various natural drugs also provide human benefits through supplements of essential elements such as Fe, Zn, Cr, Sc, Rb and Co.  相似文献   

15.
Performance characteristics (especially accuracy) of a routine INAA with k0 standardization were verified and compared with those of INAA with a classical single comparator. For this purpose, samples of three certified reference materials of environmental origin (Fly Ash, Orchard Leaves and Buffalo River Sediment—all supplied by NIST) were irradiated with both kinds of comparators (Au–Zr for k0 and Zn for classical k method) in one irradiation rabbit. Also the following steps of INAA procedure were practically the same for both standardization methods used (counting, spectral processing, etc.). The results have shown that the k0 method gives sufficiently accurate results comparable with those of the well established and routinely used single comparator (Zn) method, provided proper neutron flux monitoring, efficiency calibration and also coincidence summing corrections are applied. This work shows that modern k0 standardization method in INAA can be sucessfully used in routine practice and applied with an advantage in INAA laboratories subject to changes of neutron spectra or counting conditions.  相似文献   

16.
Journal of Radioanalytical and Nuclear Chemistry - India is a major producer of fly ash due to its coal-based thermal power plants. The elemental characterization of the fly ash facilitates its...  相似文献   

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18.
Elemental concentrations reported by 325 investigators in 16 NBS SRM's are summarized. Mean values, standard deviations and comparative data from NBS and other reviews are provided.  相似文献   

19.
Twenty marine sediment samples, selected downcore from six sediment cores, which were retrieved from the Patras Harbour, were studied for their elemental composition using three analytical techniques: INAA, ICP-MS and AAS. Standard reference materials were used to verify the accuracy of the analysis techniques. In total, the concentrations of 30 major, minor and trace elements were measured. The vertical distribution of most elements in the examined cores could be characterized as relatively uniform. The eastern part of the harbour seems to be more polluted in respect to some elements (Ag, Br, Cd, Cr, Cu, Pb and Zn) compared to the western one. The concentrations of a number of elements (As, Cd, Cr, Cu, Ni, Pb and Zn) determined in the sediment samples of the present work are discussed regarding to those obtained from other harbours in the world and compared against sediment quality guidelines (SQGs) to assess the ecotoxicological significance of the sediment contaminants to benthic biota.  相似文献   

20.
The health food Angelica keiskei, planted and consumed as an oriental herb, was sampled from five farms in Taiwan. The determination of minor and trace elements identified in the roots, fresh leaves and stems of the plant, as well as in end-products such as tea bags and capsules, is essential for estimating the recommended daily intake for ensuring optimum health safety. Samples were homogenized prior to freeze-drying, and were irradiated with a neutron flux at about 2.0.1012 n.cm-1.s-1. A total of 17 elements were analyzed using INAA. In the collected samples the elements exist in widely differing concentrations, ranging from 105 to 10-2 mg/g for different farms. We found that aluminum is more highly concentrated in roots than in any other part of the plant. Selenium was the only element analyzed down to 10-1 mg/g in the leaves. Meanwhile, arsenic was also found in the roots and stems at levels of nearly 10-2 mg/g. The elemental concentrations and maximum daily intake (MDI) of this herb are compared with those of Angelica sinensis (Danggui in Mandarin), Ligusticum chuanxiony (Chuanxiong in Mandarin) and Panax ginseng (Ginseng in Mandarin) as well as with the recommended daily dietary intake values for Taiwanese consumers, developed by the WHO.  相似文献   

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