Showing papers in "Journal of Radioanalytical and Nuclear Chemistry in 1989"
TL;DR: In this article, the authors tabulated k0-factors and related nuclear data for 112 radionuclides of interest in (n, γ) reactor neutron activation analysis.
Abstract: Abstractk0-Factors and related nuclear data are tabulated for 112 radionuclides of interest in (n, γ) reactor neutron activation analysis. Whenever relevant, critical comments are made with respect to the accuracy of literature data for e. g. isotopic abundances, half-lives, absolute gamma-intensities and 2200 m · s−1 (n, γ) cross-sections. As to the latter, a comparison is made with the values calculated from the experimentally determined k0-factors, by introduction of selected literature data for the input parameters.
175 citations
TL;DR: In this paper, the sorption-desorption of uranium (VI) on Grimsel granite of Switzerland was studied under oxidizing conditions with an initial uranium concentration range of between 9.7 · 10−7 and 4.5· 10−4M, using a batch technique.
Abstract: The sorption-desorption of uranium (VI) on Grimsel granite of Switzerland was studied under oxidizing conditions with an initial uranium concentration range of between 9.7·10−7 and 4.5·10−4M, using a batch technique. The sorption coefficients varied between 8.0 and 0.4 ml/g and sorption was not fully reversible. The data could be fitted to a Freundlich isotherm. By fitting the data with the Dubinin-Radushkevich equation, a mean energy of sorption of 10.7 kJ/mol was calculated, which corresponds to the energy of ion exchange reactions. The kinetic data could be interpreted by assuming diffusion into the crushed granite particles. The calculated pore diffusion coefficient was between 2.0·10−11–7.7·10−11 m2/s.
106 citations
TL;DR: Determination des facteurs k 0 des raies gamma de 112 radioisotopes d'interet analytique. as discussed by the authors presented de la methode experimentale and des tableaux de resultats
Abstract: Determination des facteurs k 0 des raies gamma de 112 radioisotopes d'interet analytique. Presentation de la methode experimentale et des tableaux de resultats
98 citations
TL;DR: In this paper, a new analytical technique using ICP-MS was applied to the determination of237Np in some environmental samples, which was assessed by comparison with those of conventional NAA and α-spectrometric method as well as by analysis of the intercomparison sample of Ravenglass NRPB silt.
Abstract: A new analytical technique using ICP-MS was applied to the determination of237Np in some environmental samples. The accuracy and precision of the new method were assessed by comparison with those of conventional NAA and α-spectrometric method as well as by analysis of the intercomparison sample of Ravenglass NRPB silt. The results obtained by ICP-MS were in good agreement with those by NAA or α-spectrometry at a relative deviation of 2–9%. The detection limit is 0.02 mBq/ml (26 mBq=1 ng).
40 citations
TL;DR: In this paper, the reliability of two solvent extraction techniques for the determination of Pu oxidation states in solution was tested with low-ionic-strength solutions and with high-Na and high-Mg brines that contained Pu concentrations sufficient for spectrophotometric analysis.
Abstract: The reliability of two solvent extraction techniques for the determination of Pu oxidation states in solution was tested with low-ionic-strength solutions and with high-Na and high-Mg brines that contained Pu concentrations sufficient for spectrophotometric analysis. One procedure only differentiates between reduced Pu [Pu(III) and Pu(IV)] and oxidized Pu [Pu(V) and Pu(VI)], whereas the second procedure was designed to differentiate between Pu(IV), Pu(V), and Pu(VI) in solution. Both procedures successfully differentiated between oxidized and reduced Pu in both dilute solutions and brines when tested with samples that contained only the Pu(IV), Pu(V), or Pu(VI) oxidation states. However, when the second solvent extraction procedure, which differentiates between Pu(V) and Pu(VI), was employed for solutions that did not contain a strong oxidant to maintain the Pu(VI) oxidation state, significant quantities of Pu(VI) were reduced to Pu(V) during extraction, indicating that accurate quantification of Pu(V) and Pu(VI) is not possible with this procedure.
38 citations
TL;DR: In this paper, the authors used instrumental neutron activation analysis (INAA) in several NBS and IAEA standards and samples of biological origin such as human and animal blood, cancerous tissue, edible plant leaves, diets, milk samples, etc.
Abstract: Phosphorus has been determined using the β- emitter32P by instrumental neutron activation analysis (INAA) in several NBS and IAEA standards and samples of biological origin such as human and animal blood, cancerous tissue, edible plant leaves, diets, milk samples, etc. The method involves thermal neutron irradiation for 2–10 h in a reactor followed by β--counting on an end-window gas flow proportional counter using an aluminium filter. The results are within ±10% of the certified values in most cases.
37 citations
TL;DR: Advantages of X-ray fluorescence with the use of Synchrotron Radiation are emphasized (intensity, polarization, tunability of energy). The experimental set-up and the fast computer system for the data reduction without standards are presented.
Abstract: Advantages of X-ray fluorescence with the use of Synchrotron Radiation are emphasized (intensity, polarization, tunability of energy). The experimental set-up and the fast computer system for the data reduction without standards are presented. The results are in good agreement with standard references. Examples of applications are presented: old coins and potteries were studied in archaeological domain; metal alloys were analyzed; element composition of bulk samples of volcanic rocks, sublimates and aerosols were determined.
37 citations
TL;DR: Calculated daily intake of manganese for Australian diets was compared with recommendations by US authorities for the safe and adequate dietary intake of this essential trace element.
Abstract: Fifty representative foods sampled Australia-wide from each of the State capitals were analysed for manganese by instrumental neutron activation analysis. Calculated daily intake of manganese for Australian diets was compared with recommendations by US authorities for the safe and adequate dietary intake of this essential trace element. The contribution of tea to adult daily intakes was determined.
36 citations
TL;DR: The results obtained by both methods are in agreement within the relative deviation of 9-13%. The precision in ICP-MS was found to be better than in it the FT-method as mentioned in this paper.
Abstract: Fission track /FT/ method and inductively coupled plasma mass spectrometry /ICP-MS/, that is a new analytical technique for the analysis of trace element, were used for the measurement of240Pu/239Pu ratios in environmental samples. The results obtained by both methods are in agreement within the relative deviation of 9–13%. The precision in ICP-MS was found to be better than in it the FT-method. These methods are applicable to measure the Pu isotopes ratio at low concentration levels in environmental samples.
32 citations
TL;DR: In this article, instrumental neutron activation analysis in a wide range of Australian coals and fly ash was performed to update and extend earlier measurements, which indicated a marked disequilibrium of the232Th decay series in some samples while a general enrichment of210Pb in most fly ash samples disrupted the238U equilibrium.
Abstract: Forty elements were determined by instrumental neutron activation analysis in a wide range of Australian coals and fly ash to update and extend earlier measurements. The natural radioactivity content of selected samples were analysed by high resolution gamma-ray spectrometry and low level radiochemistry. The results indicated a marked disequilibrium of the232Th decay series in some samples while a general enrichment of210Pb in most fly ash samples disrupted the238U equilibrium.
30 citations
TL;DR: From the decay of their most intense γ-ray, /or rays/, the half-lives of 24Na,31Si,49Ca,52V,139Ba,142Pr,153Sm,159Gd,165Dy,166Ho,175Yb,187W,233Th and 239U have been determined.
Abstract: From the decay of their most intense γ-ray, /or rays/, the half-lives of24Na,31Si,49Ca,52V,139Ba,142Pr,153Sm,159Gd,165Dy,166Ho,175Yb,187W,233Th and239U have been redetermined.
TL;DR: In this article, the results of instrumental neutron activation analysis of very pure silicon wafers of 12.5 and 15 cm diameter are described and it is shown that the determined contaminations are mainly present on the surface or in a surface layer of the wafer.
Abstract: Procedure and results of instrumental neutron activation analysis of very pure silicon wafers of 12.5 and 15 cm diameter are described. It is shown that the determined contaminations are mainly present on the surface or in a surface layer of the wafers. With the method outlined here very low limits of detection for a large number of elements are obtained. The analyses also confirmed that two routine process cleaning procedures do not contaminate the surface of the waters.
TL;DR: In this article, the epithermal NAA was used for rare earth element (REE) determination in acidic hot spring and crater lake waters by neutron activation analysis (NAA).
Abstract: Determination of the rare earth elements (REE's) in acidic hot spring and crater lake waters by neutron activation analysis (NAA), in which activation was performed mostly by epithermal neutrons (epithermal NAA) was investigated. Nine REE's, La, Ce, Sm, Eu, Tb, Ho, Tm, Yb and Lu, out of fourteen naturally existing REE's were determined at ppb levels with satisfactory precision. The epithermal NAA was found to be more effective in the determination of Sm, Tb, Ho and Yb than normal NAA, in which activation was performed mainly by thermal neutrons. Combined use of the epithermal and normal NAA's enabled the determination of eleven REE's, La, Ce, Sm, Eu, Gd, Tb, Dy, Ho, Tm, Yb and Lu.
TL;DR: In this article, the nonideality of the epithermal neutron flux distribution at a reactor site can be described by a 1/E1+α spectrum representation, with parameter α being a measure of the non-ideality.
Abstract: The nonideality of the epithermal neutron flux distribution at a reactor site can be described by a 1/E1+α spectrum representation, with parameter α being a measure of the nonideality. α-values were determined in 3 typical irradiation positions of the TRIGA MARK II reactor of the “Jozef Stefan” Institute, Ljubljana, Yugoslavia, using the “Cd-ratio for multi-monitor” method. The simpler “Cd-ratio for dual monitor” method (monitors:197Au−94Zr) also yielded reliable results. This characterisation is of use in the k0-method of NAA, which is recently introduced at the Institute.
TL;DR: In this article, the authors used 0.1M (NaClO4) aqueous phase and toluene to extract UO 2 2+, Am3+, and Th4+ by 1-phenyl-3-methyl-4-benzylpyrazolone with crown ethers.
Abstract: The extraction of UO 2 2+ , Am3+, and Th4+ by 1-phenyl-3-methyl-4-benzylpyrazolone with crown ethers was studies using 0.1M (NaClO4) aqueous phase and toluene. The crown ethers were 12C4, 15C5, 18C6, DB18C6 and DCH18C6. The synergic equilibrium constant did not show correlation between the cationic radii and the ether cavity size nor did the values follow a simple order of ether basicity. The ether basicity, steric effects, and the number of ether oxygens bound to the cation are the combined factors which seemingly determine the pattern of M(PMBP)n—CE interaction.
TL;DR: In this article, a very accurate and precise procedure for the determination of copper in biological materials has been devised, based on combination of neutron activation and very selective and quantitative post-irradiation separation of copper from other radionuclides by extraction chromatography, using columns with LIX 70 on Bio-Beads SM-1, followed by gamma-ray spectrometric measurement.
Abstract: A highly accurate and precise procedure deserving the name of “definitive method” has been devised for the determination of copper in biological materials. The method is based on combination of neutron activation and very selective and quantitative post-irradiation separation of copper from other radionuclides by extraction chromatography, using columns with LIX 70 on Bio-Beads SM-1, followed by gamma-ray spectrometric measurement. All potential sources of errors were carefully examined and eliminated or appropriate corrections were introduced into the procedure. The method contains several warning mechanisms safeguarding against making gross errors. Limit of detection for rather short irradiation time (tir≤1 h) (which enables radiochemical work without sophisticated shielding) amounts to 15 μg/kg. Results for copper concentration in several NBS, IAEA and other certified reference materials are presented and a new “recommended value” for IAEA's Milk Powder (A-11) is proposed.
TL;DR: In this paper, the status of trace and minor elements in some foodstuffs (cereals, vegetables, milk, egg and fish) commonly consumed in Bangladesh, using proton induced X-ray emission (PIXE) and radioisotope-induced Xray fluorescence (XRF) techniques.
Abstract: An investigation is conducted on the status of trace and minor elements in some foodstuffs (cereals, vegetables, milk, egg and fish), commonly consumed in Bangladesh, using proton induced X-ray emission (PIXE) and radioisotope-induced X-ray fluorescence (XRF) techniques. In PIXE measurements, the samples were irradiated in air with 2.0 MeV (energy on the target) protons having the beam intensity of 30 nA for characteristic X-ray excitation, while in XRF analysis, the samples were excited for 5000 seconds with a 10 mCi Cd-109 annular X-ray source. The elemental concentration of K, Ca, Mn, Fe, Ni, Cu, Zn, Se, As, Br, Rb, Sr, Mo, and Pb were determined in the samples by comparison with X-ray yield curves constructed from IAEA and NBS standard reference materials. The validity of the analytical procedures (PIXE and XRF) followed in this study has been confirmed by comparative measurements of Cu, Zn and Mn in some varieties of rice with atomic absorption spectrophotometry. The results indicate that none of the food regimes investigated here is burdened with heavy metals beyond permissible limits except five species of vegetables with chromium having the range of 0.99–3.59 mg/kg compared to the literature value of 0.0–0.36 mg/kg (dry weight basis). An average value of 0.2 mg/kg of arsenic was observed both in IRRI (n=16) and local Aman (n=12) varieties of rice and only one hen egg contained 1.7 mg/kg of lead in yolk. The zinc content in some marine fish from Bay of Bengal was reported to be 5.4–19.5 mg/kg, whereas in the present study of sweet-water fish, the level is found to be 15.2–62.1 mg/kg (fresh weight basis) for five species. In human milk, both Cu (0.12–0.25 mg/l, n=8) and Zn (0.28–1.80 mg/l, n=8) levels appear to be almost half the literature values (n=25). On the other hand formula milk has higher values of Cu (0.32–1.63 mg/kg, n=16) and Zn (5.16–19.8 mg/kg, n=16).
TL;DR: Uranium(VI) was quantitatively extracted from 6 to 8M hydrochloric acid with 0.02M DC-18-crown-6 in chloroform as discussed by the authors.
Abstract: Uranium(VI) was quantitatively extracted from 6 to 8M hydrochloric acid with 0.02M DC-18-crown-6 in chloroform. It was stripped from the organic phase with 0.5M hydrochloric acid and determined as its Arsenazo-III complex at 665 nm. Uranium(VI) was separated from several elements such as thorium, zirconium, scandium, yttrium, thallium and tin in complex mixtures. The method was extended for analysis of uranium in monazite and rock sample.
TL;DR: In this paper, the adsorption of mercury on zirconium oxide from aqueous solution has been studied in relation to concentration of adsorbent and adsorbate.
Abstract: The adsorption of mercury on zirconium oxide from aqueous solution has been studied in relation to concentration of adsorbent and adsorbate. The influence of contact time, buffer composition, pH, and foreign ions was also investigated. Thiosulfate, iodide, thiocyanate, EDTA, cyanide and Li(I) drastically reduced adsorption. Adsorption of other metal ions under the same conditions was also investigated. Based on these data, separation of mercury from antimony and neodymium can be achieved.
TL;DR: In this paper, an energy-dispersive X-ray fluorescence analysis was applied for the analysis of hair for the elements Fe, Ni, Cu, Zn and Pb.
Abstract: Energy-dispersive X-ray fluorescence analysis was applied for the analysis of hair. The hair samples were digested in a mixture of nitric and perchloric acid and the heavy metals were precipitated with ammonium pyrrolidine dithiocarbamate. The accuracy, precision and recovery of the method for the elements Fe, Ni, Cu, Zn and Pb were evaluated through the analysis of a standard hair sample. The procedure was applied to the analysis of hair from an occupationally exposed group of Sudanese workers and a control group. The hair of the exposed group showed a range of 80–550 ppm Fe, 6–12 ppm Cu, 57–190 ppm Zn and 70–3700 ppm Pb, while that of the control group had a range of 60–310 ppm Fe, 7–22 ppm Cu, 89–170 ppm Zn and 3–17 ppm Pb.
TL;DR: In this paper, the fission track registration technique using Melinex-0 as the detector has been applied to estimate uranium concentration in soil and plant samples collected from different parts of this region of India.
Abstract: The fission track registration technique using Melinex-0 as the detector has been applied to estimate uranium concentration in soil and plant samples collected from different parts of this region of India. The soil samples were powdered and plant samples were ashed to form pellets which were then irradiated with thermal neutrons. Uranium was found to vary from 0.023 to 0.430 ppm in soil samples and 0.026 to 0.216 ppm in plant (Mesophyte group) samples. Fission track technique provides simple, inexpensive, reliable and sensitive method and has high potentiality for uranium analyses in plants and agricultural crops and getting information about underlying ore and mineral deposits.
TL;DR: In this paper, an analysis of principal factors affecting the interaction of radiocobalt with freshwater solids, important for migration of radiobalt in surface streams, is presented.
Abstract: The paper aims at the analysis of principal factors affecting the interaction of radiocobalt with freshwater solids, important for migration of radiocobalt in surface streams. Uptake of radiocobalt by sediment from a small river have been studied as a function of composition of the sediment, of liquid-to-solid ratio (V/m) and of temperature, using laboratory model experiments. The study of the effect of sediment composition was based on selective extraction of the sediment prior to the uptake and indicated that radiocobalt was sorbed on several components of the sediment simultaneously, probably on clay minerals, organic matter and oxidic coatings. Relative importance of these components depends on the pH and composition of the aqueous phase and on the concentration of radiocobalt. Distribution coefficient Kd characterizing the uptake of radiocobalt is nearly independent of the V/m ratio in V/m range typical for rivers, but decreased at V/m<1.7 dm3·g−1. Increase in temperature from 13°C to 23°C accelerate radiocobalt uptake but did not affect the “equilibrium” value of the uptake. Results obtained are compared with literature data and conclusions are drawn concerning the importance of the factors studied for modelling of radiocobalt migration in rivers.
TL;DR: In this article, a rapid method for determining traces of radiostrontium in milk and drinking water is described, which involves a batch treatment of the milk sample with a cation exchanger (DOWEX 50W X8) followed by a solvent extraction with a crown ether (DC18C6) and a precipitation of SrCO3.
Abstract: A rapid method for determining traces of radiostrontium in milk and drinking water is described. The technique involves a batch treatment of the milk sample with a cation exchanger (DOWEX 50W X8) followed by a solvent extraction with a crown ether (DC18C6) and a precipitation of SrCO3. In the case of water, the strontium is extracted directly with the crown ether. The average separation yield is 74% for milk and 91% for water. The overall separation procedure takes about 8 hours. Activities as low as 0.03 Bq/1 can be determined with a low background GM-counter.
TL;DR: In this article, the authors investigated the effect of TBP on the extraction of zirconium(IV) using mixtures of Aliquat 336 or Alamine 336 with a neutral donor TBP from HCl solutions.
Abstract: Synergism has been observed in the extraction of zirconium(IV) by mixtures of Aliquat 336 or Alamine 336 with a neutral donor TBP from aq. HCl solutions. Although the extractant dependency for Zr(IV) is found to be nearly second power with respect to TBP alone, monosolvate is found to be formed for extraction by its mixture with Aliquat 336 or Almine 336. Quantitative extraction is observed with mixtures at a lower acidity than that with individual extractants. The species formed is tentatively assigned to be Q2ZrCl6. TBP, where\(Q{\mathbf{ }} = {\mathbf{ }}R_3 {\mathbf{ }}\mathop N\limits^ + (CH_3 )\) for Aliquat 336 and\(R_3 {\mathbf{ }}\mathop N\limits^ + H\) for Alamine 336.
TL;DR: The Marinelli beaker of the volume of 450 ml for the measurement of the radionuclide activity has been built in the Institute of Research, Production, and Application of Radioisotopes, according to the norm IEC 697/1981 as mentioned in this paper.
Abstract: The Marinelli beaker of the volume of 450 ml for the measurement of the radionuclide activity has been built in the Institute of Research, Production, and Application of Radioisotopes, according to the norm IEC 697/1981. For the determination of the two main correction factors, i.e. of the corrections for true summations and for the self-absorption, simple procedures have been worked out that make possible to find the correction factor for true summations with a precision better than 0.3% for the self-absorption with the precision better than 1%.
TL;DR: In this article, the dependence of the characteristic X-ray intensities on the counting geometry has been investigated for a radioisotope excited XRF spectrometer, and the collimation factor for the source-sample-detector geometry was determined both theoretically and experimentally.
Abstract: In this study, the dependence of the characteristic X-ray intensities on the counting geometry has been investigated for a radioisotope excited XRF spectrometer. The collimation factor for the source-sample-detector geometry, which was prepared for an annular type109Cd radioisotope source, has been determined both theoretically and experimentally. The discrepancy between the theoretical and experimental results is discussed in terms of possible sources of errors.
TL;DR: In this article, high enriched gaseous124Xe /99.9% was used to perform instrumental measurements of excitation functions of the 124Xe/p, 2n/123Cs and 124X e/p reactions up to the proton energy of ∼33 MeV.
Abstract: Highy enriched gaseous124Xe /99.9%/ is used to perform instrumental measurements of excitation functions of the124Xe/p, 2n/123Cs and124Xe/p, pn/123Xe reactions up to the proton energy of ∼33 MeV. Differential and integral yields of123I have also been determined /6.6 h after irradiation/.
TL;DR: Ferrous gluconate Fe(C6H11O7)2·2H2O was investigated by means of 57Fe (14.4 keV)-Mossbauer spectroscopy and thermogravimetry as discussed by the authors.
Abstract: Ferrous gluconate Fe(C6H11O7)2·2H2O was investigated by means of57Fe (14.4 keV)-Mossbauer spectroscopy and thermogravimetry. The Mossbauer study was performed in the temperature range 80 to 423 K. It was found that Fe2+ occupies two distinctly different Mossbauer sites in the hydrated phase and a single site in the product of the thermal treatment. All samples were contaminated by some amount of Fe3+. A significant oxidation occurs during thermal treatment (about 378 K) at least for the samples exposed to the air. No Goldanskii-Karyagin effect has been detected, in contrast to the previous claim. It has to be noted that the ferrous gluconate is often used as the iron containing component of drugs used in the treatment of anaemia.
TL;DR: In this paper, the authors studied the effect of pH and composition of aqueous phase on the uptake of radiocesium by bottom sediments and suspended solids from small streams.
Abstract: The paper aims at the analysis of principal factors affecting the interaction of radiocesium with freshwater solids, important for the migration of radiocesium in rivers. Uptake of radiocesium by bottom sediments and suspended solids from small streams was studied as a function of pH and composition of aqueous phase, of the concentration of cesium in water and of the composition of freshwater solids, using laboratory model experiments. pH had negligible effect on the uptake in the pH range 5–9, the uptake decreased at pH values less than 3–5 depending on the nature and concentration of the solids. Addition of cations suppressed the uptake in the order K+>Na+>Ca2+, the suppression began at 0.001, 0.01 and 0.1 mol.dm−3 concentration, respectively. Increase in cesium concentration in water caused a decrease of radiocesium uptake, but at very low concentrations of cesium combined with higher concentration of sediment (2g·dm−3) the uptake was independent of cesium concentration. Removal of carbonates, oxidic coatings and organic matter from a sediment did not affect the sorption properties of the sediment. The nature of the effects found confirms that cesium is sorbed mainly by clay components of freshwater solids. Results obtained are compared with literature data and conclusions are drawn on the importance of the factors studied for modelling of radiocesium migration in rivers.
TL;DR: In this article, free acid and uranium in uranyl nitrate solutions have been determined potentiometrically using Na2SO4−NaOH, Na 2SO4+Na2CO3 and (NH4)2SO 4+NaOH complexant-titrant combinations.
Abstract: Free acid and uranium in uranyl nitrate solutions have been determined potentiometrically using Na2SO4−NaOH, Na2SO4−Na2CO3 and (NH4)2SO4−NaOH complexant-titrant combinations. The overall recovery of nitric acid varies in the range of 95.25 to 118.5%, depending upon the acid as well as the total uranium present, while that of uranium always a positive bias ranging from 100.2 to 106.4%. The results have been discussed in light of recent available data. It has been concluded that all the complexant-titrant combinations studied provide similar results.