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1.
This paper deals with a rapid method to determine radionuclides in reactor coolant by anion, cation, and anion-cation exchange membranes. A high pressure filtration device was established to simulate the THOR cooling water sampling system by means of several membranes mentioned above. The experimental results indicate that the adsorption efficiency of each membrane for several radionuclides is /1/ >95% with cation exchange membrane for Zn, Co, Na, Mn, Cu, Cs, Ba, La, W etc., /2/ >98% with anion exchange membrane for I, and /3/ <98% with anion-cation exchange membranes for Fe and Cr. The results are obtained using cooling water of Tsing Hua Open-Pool Reactor and the following radionuclides were identified:99mTc,140Ba,140La,51Cr,131I,58Co,60Co,54Mn,46Sc,59Fe,24Na, etc.  相似文献   

2.
A method of detecting inaccessible metallic corrosion is proposed, in which a gamma-emitting radionuclide added in aqueous solution to the contents of a pipe or vessel attaches itself selectively to corrosion products, and then may be detected from outside using a hand-held gamma detector. This was simulated in the laboratory in preliminary studies. Corrosion products studied were oxidised iron, FeS, goethite, magnetite, spinel and oxidised stainless steel.K d values were derived for various radionuclides. Of the radionuclides studied,60Co,152Eu,214Pb,214Bi and226Ra seem potentially useful, but not22Na or137Cs.  相似文献   

3.
The true coincidence summing (TCS) effect on the full energy peak (FEP) efficiency calibration of an HPGe detector has been studied as a function of sample-to-detector distance using multi-gamma sources. Analytical method has been used to calculate coincidence correction factors for 152Eu, 133Ba, 134Cs and 60Co for point and extended source geometry at close sample-to-detector distance. Peak and total efficiencies required for this method have been obtained by using MCNP code by using the optimized detector geometry. The correction factors have also been obtained experimentally. The analytical and the experimental correction factors have been found to match within 1–5%. The method has been applied to obtain the activity of the radionuclides (106Ru, 125Sb, 134Cs and 144Ce) present in a fission product sample.  相似文献   

4.
In order to evaluate alternative analytical methodologies to study the geographical origin of ciders, both multi-elemental analysis and Sr isotope abundance ratios in combination with multivariate statistical analysis were estimated in 67 samples from England, Switzerland, France and two Spanish regions (Asturias and the Basque Country). A methodology for the precise and accurate determination of the 87Sr/86Sr isotope abundance ratio in ciders by multicollector inductively coupled plasma mass spectrometry (MC-ICP-MS) was developed. Major elements (Na, K, Ca and Mg) were measured by ICP-AES and minor and trace elements (Li, Be, B, Al, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, As, Se, Rb, Sr, Y, Mo, Cd, Sn, Sb, Cs, Ba, La, Ce, W, Tl, Pb, Bi, Th and U) were measured by ICP-MS using a collision cell instrument operated in multitune mode. An analysis of variance (ANOVA test) indicated that group means for B, Cr, Fe, Ni, Cu, Se, Cd, Cs, Ce, W, Pb, Bi and U did not show any significant differences at the 95% confidence level, so these elements were rejected for further statistical analysis. Another group of elements (Li, Be, Sc, Co, Ga, Y, Sn, Sb, La, Tl, Th) was removed from the data set because concentrations were close to the limits of detection for many samples. Therefore, the remaining elements (Na, Mg, Al, K, Ca, Ti, V, Mn, Zn, As, Rb, Sr, Mo, Ba) together with 87Sr/86Sr isotope abundance ratio were considered for principal component analysis (PCA) and linear discriminant analysis (LDA). Finally, LDA was able to classify correctly 100% of cider samples coming from different Spanish regions, France, England and Switzerland when considering Na, Mg, Al, K, Ca, Ti, V, Mn, Zn, As, Rb, Sr, Mo, Ba and 87Sr/86Sr isotope abundance ratio as original variables.  相似文献   

5.
Neutron activation analysis and Ge(Li) spectroscopy was used to determine 32 elements in seven U.S.G.S. standard rocks of a wide range of composition. Short half-life nuclides (10 sec-10 min) were used to measure Sc, Hf, Dy, Mg, Al, Ca, Ti, V (and Na) in an automated rabbit Ge(Li) detector system. The elements K, Cu, Zn, Ga, Sr, Ba, La, Eu, Sm (and Mn) were determined by dissolution of the irradiated sample followed by removal of24Na on hydrated antimony pentoxide (HAP). Long-lived nuclides were used to measure Sc, Cr, Fe, Co, Zr, Rb, Sb, Cs, Ba, Ce, Eu, Yb, Tb, Lu, Hf, Ta and Th after decay of24Na. The method involves little radiochemistry and the separation is selective for24Na under the experimental conditions used. Elemental concentrations determined agree well with previously published data.  相似文献   

6.
Eggshell material was used as low-cost and eco-friendly biosorbent for removal of 134Cs, 60Co and 152+154Eu radionuclides from aqueous solution. The eggshell material was calcined at 500 and 800 °C, and then characterized. Comparative studies on the natural and calcined eggshell for sorption of the three radionuclides were carried out. It was found that, the uptake is in the order: Eu(III) > Co(II) > Cs(I). Further, column chromatography was used in separation of 134Cs, 60Co and 152+154Eu using 0.15, 0.2 and 0.5 mol/l nitric acid, respectively. Eggshell material can be considered as a promising material for separation of radionuclides from radioactive waste solution.  相似文献   

7.
An intercomparison of data obtained for a moss reference material (Hylocomium splendens) used as biomonitor of atmospheric deposition by different multi-element techniques is presented. In total 43 elements (Na, Mg, Al, Cl, K, Ca, Sc, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Br, Rb, Sr, Zr, Ag, Sn, Sb, I, Cs, Ba, La, Ce, Nd, Sm, Eu, Gd, Tb, Tm, Yb, Lu, Hf, Ta, W, Au, Th, U) were determined using inductively coupled plasma-mass spectrometry (ICP-MS), conventional instrumental neutron activation analysis (INAA), epithermal neutron activation analysis (ENAA) and as well as shorttime neutron activation analysis without and with a6LiD-converter. Advantages and drawbacks of each method are discussed. The introduction of moss reference materials for atmospheric multi-element deposition studies involving nuclear analytical techniques is strongly recommended.  相似文献   

8.
Summary In the medicinal plant Thymus capitatus Hoffm. and Link the trace elements Sb, Cl, Cr, Cs, Co, Eu, Fe, Mn, K, Rb, Sc, Na and Zn were determined by neutron activation analysis and the essential oils and phenol by steam distillation and gas chromatography. Statistically significant differences were found between plants from different regions for the active constituents and for the elements Cr, Fe, Eu and Mn. These latter elements are therefore regarded as decisive factors for the increase of the active constituents (by up to 25%).
Bestimmung und Korrelation der aktiven Bestandteile und der Spurenelemente in der Heilpflanze Thymus capitatus Hoffm. und Link
Zusammenfassung In der Heilpflanze Thymus capitatus Hoffm. und Link wurden mit Hilfe der Neutronenaktivie-rungsanalyse die Spurenelemente Sb, Cl, Cr, Cs, Co, Eu, Fe, Mn, K, Rb, Sc, Na und Zn sowie durch Wasserdampfdestillation und Gas-Chromatographie die ätherischen Öle und Phenol bestimmt. Zwischen Pflanzen aus zwei verschiedenen Regionen ergaben sich für die aktiven Bestandteile sowie für die Spurenelemente Cr, Fe, Eu und Mn statistisch signifikante Unterschiede. Diese Elemente werden daher als entscheidende Faktoren für die erhöhte Konzentration an aktiven Bestandteilen (bis zu 25%) angesehen.
  相似文献   

9.
Al, As, Br, Cd, Ce, Cl, Co, Cs, Cu, Fe, Hg, K, La, Mg, Mn, Mo, Na, Sb, Sc, Sr, Ti, V and Zn were determined in the soluble and insoluble fractions of snow which was collected at 6 differents sites in the Montreal area. From these data the variability coefficients and the enrichment factors were calculated and the probable sources of each element are discussed. The overall concentrations found in the snow were compared with the concentrations of these elements in the air sampled in the same area by high volume samplers. From these, the snow-out ratios for Cr, Cu, Fe, Mn, V and Zn and their mean were calculated. They are equal to 3338, 3389, 2322, 526, 563, 2603 and 2913 m3/kg respectively.  相似文献   

10.
Résumé On décrit la détermination de traces dans le germanium, le silicium et le sélénium. En appliquant des techniques gamma spectrométriques, précédées ou non de séparations chimiques il est possible de doser les éléments suivants dans (1) germanium: As, Cu, Au, Ga, Zn, Hg, Cr, Sn, Sb, Co, In, Ni, Ir, Se, Sc, Ag, Ta, Hf et U; (2) silicium: P, Au, Sb, Ga, Fe, K, Cr, Mo, Sn, As, Co, In, Zn, Cu, W, Ta, Na, Eu, Sm, La, Sc et T1; (3) sélénium: Cl, Br, I, P, S, Te, Na, K, Cr, Fe, Co, Cu, Zn, Ga, Sc, Ag, Cd, La, W, Au et Tl. Les concentrations et ou limites de détections varient de quelques parties par million à 10−3 parties par milliard.  相似文献   

11.
Summary Diffusions of85Sr,137Cs,60Co and125I radionuclides have been studied in borecore samples from Boda siltstone/claystone formation (BCF) under ambient and in situ conditions. In-diffusion (85Sr,137Cs,60Co and125I) and through-diffusion measurements (125I) were performed at ambient conditions, and for iodine, in-diffusion measurements were also carried out at in situ conditions (100 bar, 50 °C). In the case of cationic species carrier-containing solutions were also applied.60Co was detected only in the first slice of borecore at each sample, while137Cs was detected also in the first-, second- and third slices according to the concentration-increase of inactive carrier. Among the investigated cations,85Sr exhibited the fastest diffusion rate with 2.7-6.0 . 10-12m2/s apparent diffusivity values. In the course of in-diffusion measurements 4.7 . 10-11 m 2 /s, during through-diffusion investigations 1.4-1.6 . 10-12m2/s and at in situ conditions 5.0-8.0 . 10-12 m2/s apparent diffusivities were obtained for125I.Modest sorption of125I can also be deduced from the results.</p> </p>  相似文献   

12.
A group separation scheme has been developed for radiochemical neutron activation analysis for Ca, Cu, Zn, Ga, Rb, Sr, Zr, Sb, Cs, Ba, La, Nd, Sm, Eu, Gd, Tb, Ho, Tm, Yb, Lu, Hf, Ta, W and Th in a wide variety of silicate rocks and minerals, especially ultrabasic rocks and mafic minerals. The samples are decomposed in a hydrofluoric acid-nitric acid mixture in a PTFE-lined bomb. The soluble fluorides (Cu, Zn, Ga, Rb, Zr, Sb, Cs, Ht, Ta, W and Pa) are separated into three groups of elements by sequential elution from a cationexchange resin. The insoluble fluorides (Ca, Rb, Sr, Cs, Ba and REE) are dissolved and purified from interfering iron and scandium activities by extraction with tri-n-butyl phosphate. If necessary, the four main groups can be purified further from interfering activities such as 59Fe, 51Cr and 60Co. The accuracy and reproducibility of the procedure were tested by repeated analysis of U.S. Geological Survey standard granite G-2, andesite AGV-1 and dunite DTS-1.  相似文献   

13.
Forty elements in IAEA-331 (Spinach), an intercomparison material, have been determined using NAA. Among them, 30 elements, Ag, Al, Ba, Br, Ca, Ce, Cl, Co, Cr, Cs, Eu, Fe, Hf, K, La, Mg, Mn, Na, Ni, Rb, Re, Sc, Se, Sr, Ta, Tb, Th, V, Zn and Zr were determined by INAA. A series of simple and quantitative radiochemical separation procedures were established for the determination of ten additional elements. Cd, Lu, Mo, Sb, Sm, Yb, U were determined by removing the major interfering nuclide82Br. Cu was determined by 0.048M NaDDTC/CHCl3 extraction from 1M HCl medium. As and P were determined using an inorganic exchange column of acid aluminium oxide (AAO). Integral counts from 80 keV to 130 keV contributed by Bremsstrahlung from32P -were used to evaluate the content of phosphorus.  相似文献   

14.
NIST standard reference material SRM 2783 was employed to validate a high temperature, high pressure, two-stage microwave assisted acid digestion procedure using HNO3, HF and H3BO3 developed for the analysis of trace elements (including rare earths) in atmospheric fine particulate matter (PM2.5) prior to inductively coupled plasma mass spectrometry (ICP-MS). This method quantitatively solubilized Na, Mg, Al, K, Ti, V, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Rb, Sb, Cd, Cs, Ba, Pb, Th, U and several rare earth elements (REEs) (La, Ce, Pr, Nd, Gd, Dy, Er, Sm and Eu) from SRM 1648 and SRM 2783. A small amount of HF in the first stage was required to dissolve silicates necessitating the corresponding addition of H3BO3 in second stage to dissolve fluoride precipitates of Mg, La, Ce and Th. The optimized microwave dissolution—ICP-MS method detected Na, Mg, Al, K, Ti, V, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Rb, Sr, Cd, Mo, Sb, Cs, Ba, La, Ce, Pr, Nd, Sm, Gd, Pb, Th and U at trace to ultra-trace levels in ambient airborne fine particles from three sites in North Carolina. La to light lanthanide signature ratios suggested that soil and motor vehicles are the dominant REE sources in SRM 2783 and PM2.5 samples collected during this study.  相似文献   

15.
The fruit bodies of wild-growing higher fungi (macromycetes), commonly called mushrooms, of various genera and species collected in localities with different geochemical features and man-made burden in the Czech Republic were analyzed by different modes of activation analysis. The elements Na, Mg, Al, S, Cl, K, Ti, V, Mn, Cu, Br, Ba and Dy were determined by short-term instrumental neutron activation analysis (INAA). Short-term epithermal INAA (ENAA) was used for determination of I and other elements, such as Rb, Ag, and U. The elements Na, K, Sc, Cr, Fe, Co, Cu, Zn, As, Se, Br, Rb, Ag, Cd, Sb, Cs, Ba, La, Ce, Sm, Eu, Hf, Au, Hg and Th were determined by long-term INAA, whereas long-term ENAA enabled determination of several other elements, such as Ni, Ta, W and U. The analytical possibilities of instrumental photon activation analysis (IPAA) using a microtron were also explored and found useful for determination of several additional elements, namely Sr, Y, Zr, Nb, and Pb. High concentrations of several essential and toxic trace elements found (up to hundreds of mg.g-1, dry mass) should be of concern in nutritional studies, because mushrooms form non-negligible part of diet in many countries, especially in Middle and East Europe.  相似文献   

16.
Since the early days of mankind, plants have been used as food and for medicinal purposes. Still, little information exists in literature about the activity concentration of 238U and 232Th decay products, as well as stable element concentrations in Brazilian plants. Activity concentrations of 226Ra, 228Ra and 210Pb, and chemical concentrations of As, Ba, Br, Cs, Co, Cr, Cu, Eu, Fe, Hf, La, Lu, Rb, Sb, Sc, Sm, Ta, Tb, Yb, Zn and Zr were determined in ten samples commonly used in Brazilian medicinal plants.  相似文献   

17.
In order to assess the source of pollutants and the atmosphere quality in and around a thermal power plant, fugitive dust particulates from seven different locations and ambient air dust from six locations have been analyzed for 32 elements (As, Au, Ba, Br, Ce, Cl, Co, Cr, Cs, Cu, Eu, Fe, Ga, Hg, Hf, K, La, Lu, Mg, Mn, Na, P, Rb, Sb, Sc, Se, Ta, Tb, Te, Th, W and Yb) by employing instrumental neutron activation analysis (INAA). The method involves the irradiation of samples and comparator standards in a thermal neutron flux range of 1012–1013 n·cm–2·s–1 in a nuclear reactor for 10 min and 1 day followed by high resolution -spectrometry. Wide differences have been observed in the mean elemental concentrations of Fe, Co, Br, Mn, As, P. Ba and Cu in fugitive and ambient dust particulates coliected from these different locations. Further, a comparison of the elemental contents of the dust particulates from the plant with environmental standards (Urban Particulate Matter, Coal Fly Ash, Vehicle Exhaust and Coal) show significantly lower or comparable amounts of toxic and pollutant elements in the environmental samples.  相似文献   

18.
Tobacco smoking/chewing has been a cause of concern because of it being related with oral cancer. It causes stimulation and ill physiological effects. Ten different brands of spit tobacco, eight gutkaas and five paan masalas have been analyzed for seven minor (Al, Na, K, Ca, Cl, Mg, and P) and 17 trace (As, Ba, Br, Co, Cr, Cs, Cu, Eu, Fe, Hg, La, Mn, Rb, Sb, Sc, Th, and Zn) elements by instrumental neutron activation analysis. Also Ni and Pb were determined by atomic absorption spectrophotometry. Concentration of Cd was below detection limit (<10?mg?kg?1) in the tobacco samples. Mg, generally added as MgCO3 to prevent caking, is present as minor constituent in spit tobacco and gutkaas but is below detection limit (<1?g?kg?1) in paan masalas. Most elemental concentrations vary in a wide range depending on the nature of chewing tobacco. Spit tobacco has been found to be more enriched in essential elements (Ca, K, Na, P, Mn, and Rb), whereas gutkaas contain higher concentrations of Fe, Cr, Cu, and Zn. Paan masalas contain lower contents of other elements but higher content of Hg. Gutkaas also contain higher amounts of As and Pb. Further glutamic acid has been separated from tobacco leaves and characterized as it might bind with some elements.  相似文献   

19.
Neutron activation analysis (NAA) for the determination of some trace elements in biological materials is described. The method presented permits the simple and rapid determination of Se, Ag, Au, Sb, Pt (via199Au), Hg, Co, Ni (via58Co), Fe, Zn, Mo, Sn, Cr, Cd, Cu and As after radiochemical separation from Na, K, Cs, Rb and partially Br. For this purpose, postirradiation separation by extraction with mercury or zinc amalgam was used. Separation of gold by extraction with ethyl acetate or by precipitation with dimethylglyoxime was applied for the determination of gold and platinum in biological materials.  相似文献   

20.
Analyses for certification have been made by instrumental neutron activation analysis (INAA) for the determination of 21 elements in the National Institute of Standards and Technology (NIST) Spinach renewal reference material, SRM 1570a. Elements determined included ones with short halflife products (Al, V, Ca, Mg), intermediate halflife products (Mn, Na, K, La), and long halflife products (Ba, Co, Cr, Cs, Eu, Fe, Rb, Sb, Sc, Se, Sr, Th, and Zn). For the first time a new robotic sample changer was used in the counting of long halflife indicator isotopes for certification of an SRM. Uncertainties obtained averaged±1.80% for the four major and minor constituents (Ca, K, Mg, Na); ±3.14% for elements with concentrations from 1 to 400 mg/kg (Al, Ba, Cr, Fe, Mn, Rb, Sr, and Zn); and±8.31% for the ultra trace elements (<1 mg/kg) (Co, Cs, Eu, La, Sb, Sc, Se, Th, and V).  相似文献   

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