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1.
Instrumental neutron activation analysis for assessing homogeneity of a whole rice candidate reference material 总被引:1,自引:0,他引:1
Lilian Seiko Kato Elisabete A. De Nadai Fernandes Márcio Arruda Bacchi Camila Elias Silvana R. Vicino Sarriés Gabriel Adrián Sarriés Paula Sancinetti Modolo 《Journal of Radioanalytical and Nuclear Chemistry》2013,297(2):271-275
A whole rice reference material was prepared for use in quality control of trace elements in rice and in similar matrices. This study aimed at evaluating the homogeneity of the material. As, Br, Co, Cs, Fe, K, Na, Rb and Zn were determined in the samples by instrumental neutron activation analysis. The material is homogeneous for the elements determined (p < 0.05), except for Co and Fe, which presented dispersion of results much higher than the predicted degree of repeatability. 相似文献
2.
Y. S. Khrbish I. O. Abugassa N. Benfaid A. A. Bashir 《Journal of Radioanalytical and Nuclear Chemistry》2007,271(1):63-69
Cement is widely used as a construction material in Libya. Production plants introduce certain contaminants to the environment.
The dust from such plants is carried away to neighbouring areas. This dust contains a substantial amount of contaminants depending
on the origin of clays used in the production. In this study, a survey of elemental concentration of clay and cement was carried
out to assess the environmental impact of such plants, especially those that are situated near residential and agricultural
areas. Cement and clay samples, imported and locally produced, were analyzed. Instrumental neutron activation analysis was
utilized to determine the elemental concentration of As, Ca, Ce, Co, Cr, Eu, Fe, Hf, La, Na, Rb, Sb, Sc, Sm, Ta, Th, U, Yb
and Zn. Elevated concentrations of U and Th were found in a number of cement samples. The two nuclides are part of an elaborate
decay scheme producing a range of radioactive elements, which emit alpha-, beta- and gamma-radiation. With 40K, they could give elevated levels of background radiation in buildings resulting in higher exposure doses. This could pose
a health hazard and a detrimental effect on the well being of residents, especially in poor ventillated buildings. Also, cement
is the main component for constructing underground reservoirs for collecting rainwater for drinking in private residences,
so some harmful elements could leach into water. This is the first comprehensive survey of commercial cement brands and clays
used in Libya. These results are intended to build a database for trace element concentrations using INAA. 相似文献
3.
4.
N. A. Shilo E. G. Ippolitov V. V. Ivanenko B. N. Kustov V. V. Zheleznov G. N. Aristov A. S. Shtan I. N. Ivanov V. V. Kovalenko N. B. Kondrat’ev 《Journal of Radioanalytical and Nuclear Chemistry》1983,79(2):309-316
A facility using a californium neutron source and a method for the neutron activation analysis of gold were developed. The
sensitivity of the determination is 0.1 g/t. The sources of random and systematic errors have been studied. It has been concluded
that in prospection and evaluation of gold ore deposits, the traditional test tube analysis for gold may be replaced with
the developed method. 相似文献
5.
Bromine was determined by instrumental neutron activation analysis in tissues and organs of pigs as an indicator of brominated vegetable oil residues. The bromine content was found to be dose-related. An advantage of this technique is that the sample was not treated chemically. The analyses were done with the aid of an automatic sample changer and computer reduction of the data. Rapid and reliable analyses were obtained at the p.p.m. level. 相似文献
6.
S. M. Lin C. H. Chiang C. H. Huang C. L. Tseng M. H. Yang 《Journal of Radioanalytical and Nuclear Chemistry》1985,96(2):153-160
Five kinds of urinary stones from 42 patients have been determined for a total of 19 elements by instrumental neutron activation analysis. Of these elements, Ca, Mg, Sr, Na, and Cl are found to be present in the core of all kinds of stones. The differences in elemental composition among the different kinds of stones as well as across the layers of stone are statistically evaluated. 相似文献
7.
P. Schramel W. Schmolke H. Muntau 《Journal of Radioanalytical and Nuclear Chemistry》1979,50(1-2):179-184
Homogeneity is the first and most essential prerequisite of a reference material which merits this marking. A possible way
to do homogeneity tests on many elements is offered by instrumental neutron activation analysis. It is shown that this method
allows the quick evaluation of sample homogeneity on very small samples and for many elements simultaneosly, regarding macro
as well as ultra trace elements. 相似文献
8.
Instrumental neutron activation was used for the determination of 23 trace and minor elements in 4 different samples of brewer's
yeast. Detection limits for these elements vary from 2 ppb to 100 ppm. The following average concentrations were found (ppm,
dry weight): Al 597, Br 0.36, Cl 1473, Co 0.21, Cu 19, Fe 285, K 16 400, Mg 1355, Mn 8.4, Na 2330, Rb 19, Sb 0.053, Se 1.2,
V 2.2 and Zn 80. NBS standard 1569 was also analyzed and the following concentrations (in ppm) were measured: Al 2300, Br
0.65, Ce 0.23, Cl 460, Co 0.26, Cr 2.12, Cu 11, Fe 707, Gd 7.1, Hf 0.13, K 15 500, Mg 1780, Mn 7, Na 510, Rb 16, Sb 0.075,
Sc 0.18, Se 0.92, Th 3.7, Ti 38, U 0.49, V 4.1 and Zn 70. 相似文献
9.
S. Tadjiki H. N. Erten J. Erten 《Journal of Radioanalytical and Nuclear Chemistry》1995,199(4):309-316
Instrumental neutron activation analysis has been used to determine 15 trace elements in twelve blood serum samples taken from healthy students at Bilkent University in Ankara. The method allowed the determination of Sc, Cr, Mn, Fe, Co, Zn, Se, Rb, Cs, Ce, Eu, Tb, Hf, Ta and Hg, which occur at the g.ml–1 to ng.ml–1 levels. There are no values reported for Tb, Hf, Ce, Eu and Ta before. The other results are compared with the values reported in the literature. Most are in the range of the reported values except for Fe, Zn, Se and Cs. 相似文献
10.
A procedure has been developed for the detection of gunpowder residues deposited on the hand of a person firing a gun. The
method is based on neutron activation analysis of the antimony level on the surface of the hand. The surface materials are
removed by a film made by spraying a 4% solution of cellulose acetate in acetone, which sets to form a thin film that can
readily be stripped off. This technique was found to be preferable to the paraffin-lift technique which is in common use.
Following neutron activation of the film in a nuclear reactor, antimony is assayed by high-resolution Ge(Li) spectrometry
without prior chemical processing. The sensitivity of the method is about 5·10−9 g Sb, with a precision of about ±10% at a neutron flux of 5·1013 n·cm−2·sec−1. Analysis of twenty samples taken from the hands of persons who had fired a pistol gave Sb levels of 0.4±0.2 μg, compared
with 0.024±0.013 μg found on the hands of persons who had not fired a revolver. The possible extension of the present technique
to include the determination of additional elements is discussed.
Project carried out with the support of the Office of the Chief Scientist to the Ministry of Defense and with the collaboration
of the Israel Police. 相似文献
11.
A group of 27 tobacco samples was submitted to INAA. Bowen's Kale was analyzed with the samples. The resulting data for 21
elements in tobacco were processed by a cluster programme. This combination proves to be a convenient tool for discrimination
within one group of samples. 相似文献
12.
S. Ahmad M. S. Chaudhary I. H. Qureshi 《Journal of Radioanalytical and Nuclear Chemistry》1981,67(1):119-125
An instrumental neutron activation analysis technique has been developed for the simultaneous determination of up to 30 elements
including major, minor and trace elements in Obsidian Rock (a proposed NBS-SRM-278). INAA method involves both short and long
irradiations followed by gamma-ray activity measurement with a Ge(Li) detector. The accuracy of the procedure has been checked
by analyzing IAEA Reference Materials. 相似文献
13.
H. A. Das J. Zonderhuis R. Rose 《Journal of Radioanalytical and Nuclear Chemistry》1972,11(2):273-281
The possibilities are discussed of the instrumental activation analysis of phosphorus in rocks by the reaction31P(n, γ)32P (T=14.2 d). Results are given for six standard rocks of the U.S. Geological Survey. 相似文献
14.
A scheme for INAA of pottery is proposed. The combination of 3 irradiations-epithermal and pile (short and long time) and 6 measurements (2 times after each irradiation) enables the determination of Al, As, Au, Ba, Br, Ce, Co, Cr, Cs, Dy, Eu, Fe, Hf, K, La, Lu, Mg, Mn, Na, Nd, Rb, Sb, Sc, Si, Sm, Ta, Tb, Th, Ti, U, V and Yb. The accuracy and precision of the method is evaluated by analysis of standard reference materials (USGS-BCR-1, USGS-W-1, ZGI-TB). The applicability of the method is demonstrated by analysis of 15 sgraffito ceramics from XV–XVIII cc. from Tzarevetz, Veliko Tirnovo (Bulgaria). The results from the clustering of the analytical data are presented and discussed. 相似文献
15.
H. Wänke H. Kruse H. Palme B. Spettel 《Journal of Radioanalytical and Nuclear Chemistry》1977,38(1-2):363-378
We describe the scheme of sequential neutron activation which was developed in our laboratory especially for the analysis
of lunar samples and in which more than 50 elements are determined. Irradiations with 14 MeV, epithermal and thermal neutrons
and both instrumental techniques and radiochemical separations were applied. It is shown that the achieved accuracy can compete
with the best available analytical methods for most major and many trace elements. Besides the observation of “correlated
elements”, the discovery of primary matter of the last accretion stage of the moon in samples from the lunar highlands is
discussed in some detail. 相似文献
16.
The high thermal neutron flux provided by the CIRUS reactor (1×1013 n cm–2s–1) has been used to determine elements having long half-lives or poor thermal neutron crosssections. Selective cooling time and the use of a high resolution HPGe detector in conjunction with a PC based MCA unit have made it possible to analyze many elements in a single irradiation run. The method developed has been used for the analysis of ores such as Ilmenite, Rutile, Sillimanite, Garnet, Zircon and Monazite. 相似文献
17.
Y. G. Liu E. J. Trione J. C. Laul R. A. Schmitt 《Journal of Radioanalytical and Nuclear Chemistry》1982,69(1-2):427-439
The concentrations of seventeen elements in two species of fungus which cause wheat bunt disease,Tilletia caries (DC.) Tul. andTilletia controversa Kühn, were determined by instrumental neutron activation analysis. Differences in the K and Cl concentrations between these
two species of spores are large and therefore can be used as a criterion for distinguishing between the two species of fungus. 相似文献
18.
The single comparator method in neutron activation analysis has been applied to the investigation of the purity of silicon
single-crystals of different origins. The following impurities were determined: Au, Sb, Co, Cu and Na. Studies were also carried
out on the surface contamination of silicon samples introduced through steps of sample preparation and irradiation. Up to
nineteen elements on the surface of samples were analysed and found to be easily reduced to low levels or detection limits
by washing and etching. 相似文献
19.
W. E. Kuykendall Jr. L. E. Fite R. E. Wainerdi 《Journal of Radioanalytical and Nuclear Chemistry》1974,19(2):351-358
Résumé La mesure de traces d'éléments dans l'air ambiant a fait l'objet d'une attention accrue ces derniers mois, en raison d'un
intérêt grandissant pour les dangers en puissance pour la santé, qui résultent de l'exposition prolongée à certaines substances
toxiques. L'analyse par activation neutronique a été employée avec succès dans la recherche de traces d'éléments, et ce, pour
un grand nombre d'études de l'environnement; elle semble convenir de fa?on idéale pour la détermination non-destructive multi-élémentaire
de la composition de milieux de particules portées par l'air. Dans cet article, on rend compte des performances de l'analyse
instrumentale par activation neutronique comme on le montre dans le cas de 40 échantillons d'air filtrées provenant d'une
zone métropolitaine.
相似文献
20.
L. -Y Sun M. R. Conrady R. A. Schmitt 《Journal of Radioanalytical and Nuclear Chemistry》1984,81(2):323-331
Sodium contents in seven mixtures of biological materials from varying aliquants of wheat flour and oyster tissue were analyzed using the INAA (instrumental neutron activation analysis) method. The samples were activated in the thermal column (TC) of the 1 MW TRIGA reactor at our laboratory. To analyze and compare the measured results, the ratioa of the epithermal neutron flux to the thermal neutron flux was determined in the TC, the rotating rack (RR) and the pneumatic terminal (PT). Due to the negligible interferences of24Mg(n, p)24Na and27Al(n, )24Na to23Na(n, )24Na, the Na results were obtained with 97% accuracy and 99% precision. It is shown that the method is suited for accurately determining Na contents in 12 various biological materials, especially for the samples that are low in Na content. From the cadmium ratio measurements of Au (4.9 eV resonance of198Au) and Sm (8 eV resonance of153Sm), ratios ofae/0 were determined at 0.0011, 0.052 and 0.053 in the TC, RR and PT activation positions, respectively. 相似文献