scholarly journals Determination of 234U isotope in uranium-bearing materials by high-resolution gamma-spectrometry

2018 ◽  
pp. 41-46
Author(s):  
D. V. Kutnii
Keyword(s):  
Measurement Error ◽  
Standard Samples ◽  
Software Products ◽  
Isotopic Analyses ◽  
Absolute Efficiency ◽  
Bearing Materials ◽  
Intrinsic Efficiency ◽  
Enriched Uranium ◽  
Isotope Content

The paper presents research of the existing methods of non-destructive quantitative determination of 234U isotope content in uranium bearingmaterials. Also alternative method is proposed, which is based on the approach of detector calibration on “intrinsic” efficiency. The method is based on finding the ratio of the 234U and 235U isotopes activities using their most intense gamma lines in the energy range of 120...210 keV and as a consequence does not require an estimate of the absolute efficiency of registration of the gamma detector. Certified reference standard samples of uranium-bearing materials CRM 969 and CRM 146 were used as research samples (interval of investigated enrichments on 235U 0,3…93 %), measurements were performed by means of broad-energy detector based on high-purity germanium BeGe 3830 (Canberra, USA) with area 36 cm2 and thickness 3 cm. It was shown that using of the up-to-date software products for isotopic analyses of uranium (MGAU, FRAM) it is difficult to perform of reliable estimation of 234U isotope content in depleted and natural samples due to significant measurement error (from 35 % to 100 %). In case of analyses of enriched uranium the software code MGAU systematically underestimates the content of 234U on 20…30 %. Use of alternative approach for calibration of detector on “intrinsic” efficiency for analyses of 234U results in decrease of measurement error up to 7,5 % in the whole range of enrichment on 235U (0,3…93 %) and investigated concentrations of 234U (20…9800 μg/g). The proposed method does not demand standard samples for equipment calibration and not depend on physical (chemical) form of investigated material and geometry of measurements.

scholarly journals DETERMINATION OF THE 234U ISOTOPE CONTENT IN URANIUM-BEARING MATERIALS USING HIGH-RESOLUTION GAMMA SPECTROMETRY

2021 ◽  
pp. 81-85
Author(s):  
D.V. Kutniy ◽  
D.D. Burdeinyi ◽  
N.N. Savchenko
Keyword(s):  
Standard Samples ◽  
Physical Chemical ◽  
Alternative Approach ◽  
Wide Range ◽  
Bearing Materials ◽  
Intrinsic Efficiency ◽  
Non Destructive ◽  
High Resolution Gamma Spectrometry ◽  
Isotope Content

The paper presents an overview of the research into the available non-destructive methods of determining the 234U isotope content in uranium-bearing materials. An alternative approach to a problem of detector calibration by the characteristic “intrinsic” efficiency is proposed. Certified reference uranium-bearing materials CRM 969 and CRM 146 (a range of 235U enrichments studied was 0.3…93%) were used as test samples, measurements were carried out with a wide-range energy detector based on the high-purity BeGe 3830 germanium (Canberra, USA) with 38 cm2 area and 3 cm thickness. An approach used for the “intrinsic” efficiency calibration for the 234U analysis permits to decrease the measurement error to 7.5% in the whole range of 235U enrichment (from 0.3 to 93%) and 234U concentrations (20 to 9800 µg/g). The proposed method does not demand standard samples for equipment calibration and does not depend on the physical (chemical) form of the investigated material and measurement geometry.

scholarly journals Enrichment determination of low – enriched uranium material by gamma spectroscopic method

2014 ◽  
Vol 4 (2) ◽  
pp. 1-6
Author(s):  
Van Loat Bui ◽  
Van Quan Nguyen ◽  
Tuan Anh Le ◽  
Van Bay Nguyen ◽  
Thi Hong Bui ◽  
...  
Keyword(s):  
Spectroscopic Method ◽  
Efficiency Calibration ◽  
Uranium Enrichment ◽  
Activity Ratios ◽  
Intrinsic Efficiency ◽  
Enriched Uranium ◽  
Non Destructive ◽  
Good Agreement

In this work the non - destructive gamma spectroscopic method for determination of uranium enrichment is presented. In order to determine the uranium enrichment the activity ratios of 234U/235U and 238U/235Uwere measured. The activity ratios234U/235U and 238U/235U were determined by using intrinsic efficiency calibration. As a test of this method, low - enriched uranium standard was measured, the obtained result was in good agreement with the estimated value.

Dc arc emission analysis of rare earth metals and their oxides with sorption preconcentration of impurities

2018 ◽  
Vol 84 (11) ◽  
pp. 9-14
Author(s):  
E. S. Koshel ◽  
V. B. Baranovskaya ◽  
M. S. Doronina
Keyword(s):  
Rare Earth ◽  
Rare Earth Metals ◽  
Analytical Signal ◽  
Graphite Powder ◽  
Atomic Emission ◽  
Standard Samples ◽  
Emission Analysis ◽  
Sorption Preconcentration ◽  
Sample Shape

The analytical capabilities of arc atomic emission determination of As, Bi, Sb, Cu, Te in rare earth metals (REM) and their oxides after preparatory group concentration using S,N-containing heterochain polymer sorbent are studied on a high-resolution spectrometer “Grand- Extra” (“WMC-Optoelectron-ics” company, Russia). Sorption kinetics and dependence of the degree of the impurity extraction on the solution acidity are analyzed to specify conditions of sorption concentration. To optimize the procedure of arc atomic emission determination of As, Bi, Sb, Cu, and Te various schemes of their sorption preconcentration and subsequent processing of the resulted concentrate with the addition of a collector at different stages of the sorption process have been considered. Graphite powder is used as a collector in analysis of rare earth oxides due to universality and relative simplicity of the emission spectrum. Conditions of analysis and parameters of the spectrometer that affect the analytical signal (mass and composition of the sample, shape and size of the electrodes, current intensity and generator operation mode, interelectrode spacing, wavelengths of the analytical lines) are chosen. The evaporation curves of the determinable impurities were studied and the exposure time of As, Bi, Sb, Cu, and Te in the resulted sorption concentrate was determined. Correctness of the obtained results was evaluated using standard samples of the composition and in comparisons between methods. The results of the study are used to develop a method of arc chemical-atomic emission analysis of yttrium, gadolinium, neodymium, europium, scandium and their oxides in a concentration range of n x (10-2 - 10-5) wt.%.

Sorption of Se (IV) from aqueous solutions with subsequent determination by X-ray fluorescence analysis

2020 ◽  
Vol 86 (10) ◽  
pp. 5-9
Author(s):  
D. G. Filatova ◽  
A. A. Arkhipenko ◽  
M. A. Statkus ◽  
V. V. Es’kina ◽  
V. B. Baranovskaya ◽  
...  
Keyword(s):  
Inductively Coupled Plasma ◽  
Fluorescence Analysis ◽  
Standard Samples ◽  
Phase Contact Time ◽  
Sorbent Phase ◽  
X Ray ◽  
Fundamental Parameters ◽  
Inductively Coupled ◽  
Subsequent Determination

An approach to sorptive separation of Se (IV) from solutions on a novel S,N-containing sorbent with subsequent determination of the analyte in the sorbent phase by micro-x-ray fluorescence method is presented. The sorbent copolymethylenesulfide-N-alkyl-methylenamine (CMA) was synthesized using «snake in the cage» procedure and proven to be stable in acid solutions. Conditions for quantitative extraction of Se (IV) were determined: sorption in 5 M HCl or 0.05 M HNO3 solutions when heated to 60°C, phase contact time being 1 h. The residual selenium content in the solution was determined by inductively coupled plasma mass spectrometry (ICP-MS) using 82Se isotope. The absence of selenium losses is proved and the mechanism of sorption interaction under specified conditions is proposed. The method of micro-x-ray fluorescence analysis (micro-RFA) with mapping revealed a uniform distribution of selenium on the sorbent surface. The possibility of determining selenium in the sorbent phase by micro-RFA is shown. When comparing the obtained results with the results of calculations by the method of fundamental parameters, it is shown the necessity of using standard samples of sorbates to obtain correct results of RFA determination of selenium in the sorbent phase.

scholarly journals Investigations on historical monuments’ deterioration through chemical and isotopic analyses: an Italian case study

2021 ◽  
Author(s):  
Maria Ricciardi ◽  
Concetta Pironti ◽  
Oriana Motta ◽  
Rosa Fiorillo ◽  
Federica Camin ◽  
...  
Keyword(s):  
Potassium Nitrate ◽  
Sewage Water ◽  
X Ray Diffraction ◽  
Italian Case ◽  
Historical Monuments ◽  
Isotopic Analyses ◽  
Historic Centre ◽  
The Church

AbstractIn this paper, we analysed the efflorescences present in the frescos of a monumental complex named S. Pietro a Corte situated in the historic centre of Salerno (Campania, Italy). The groundwater of the historic centre is fed by two important streams (the Rafastia and the Fusandola) that can be the sources of water penetration. The aims of this work are to (i) identify the stream that reaches the ancient frigidarium of S. Pietro a Corte and (ii) characterize the efflorescences on damaged frescos in terms of chemical nature and sources. In order to accomplish the first aim, the water of the Rafastia river (7 samples) and the water of the Fusandola river (7 samples) were analysed and compared with the water of a well of the Church (7 samples). The ionic chromatography measurements on the water samples allowed us to identify the Rafastia as the river that feeds the ancient frigidarium of S. Pietro a Corte. To investigate the nature and the origin of the efflorescences (our second aim), anionic chromatography analyses, X-ray diffraction measurements, and the isotopic determination of nitrogen were performed on the efflorescences (9 samples) and the salts recovered from the well (6 samples). Results of these analyses show that efflorescences are mainly made of potassium nitrate with a δ15N value of + 9.3 ± 0.2‰. Consequently, a plausible explanation for their formation could be the permeation of sewage water on the walls of the monumental complex.

Mechanical Behaviour of CoCrMo Alloy with Si Content

2015 ◽  
Vol 754-755 ◽  
pp. 1017-1022 ◽  
Author(s):  
Petrică Vizureanu ◽  
Mirabela Georgiana Minciună ◽  
Dragoş Cristian Achiţei ◽  
Andrei Victor Sandu ◽  
Kamarudin Hussin
Keyword(s):  
Tensile Strength ◽  
Chemical Composition ◽  
Testing Machine ◽  
Base Material ◽  
Optical Emission ◽  
Experimental Tests ◽  
Optical Emission Spectrometry ◽  
Emission Spectrometry ◽  
Standard Samples

.The paper present aspects about the obtaining of non-precious dental alloys (type CoCrMo and CoCrMoSi7), the determination of chemical composition by optical emission spectrometry and the experimental tests for determining the tensile strength, made on standard plate samples. The base material used in experiments was a commercial alloy, from CoCrMo system, which belongs to the class of dental non-precious alloys, intended to medical applications. The obtaining of studied alloy was made on arc re-melting installation, under vacuum, type MRF ABJ 900. The process followed to realize a rapid melting, with a maximum admissible current intensity. The samples for tests were obtained by casting in an electric arc furnace, under vacuum, in optimal conditions for melting and solidification and processing by electro-erosion, to eliminate all the disturbing factors which come by processing conditions for the samples. The determination of chemical composition for cobalt based alloys, by optical emission spectrometry, was made on SpectromaxX equipment with spark. The electrical discharge is made with the elimination of an energy quantity, fact which determine plasma forming and light issue. Tensile tests for standard samples, made from cobalt based alloy, was made on Instron 3382 testing machine, and assisted by computer. The obtained results are: elongation, elasticity modulus, tensile strength and offer complete information about the analyzed mechanical properties. For the certitude of obtained experimental results, the tests were made on samples with specific dimensions according ISO 6892-1:2009(E) standard, both for the tensile strength, and also machine operation.

PRELIMINARY EVALUATION OF PATIENT RADIATION DOSES DURING RADIONUCLIDE DIAGNOSTIC WITH MONOCLONAL ANTIBODIES LABELED WITH 89Zr

2021 ◽  
Author(s):  
Larisa A. Chipiga ◽  
Anna E. Petrova ◽  
Artem A. Mosunov ◽  
Laura T. Naurzbaeva ◽  
Stanislaus M. Kushnarenko ◽  
...  
Keyword(s):  
Monoclonal Antibodies ◽  
Dose Assessment ◽  
Published Data ◽  
Radiation Doses ◽  
Preliminary Evaluation ◽  
Software Products ◽  
Absorbed Doses ◽  
Order Of Magnitude ◽  
Effective Doses

In connection with the constantly increasing use of monoclonal antibodies labeled with 89Zr, in clinical practice, it is urgent to study their pharmacokinetics with the determination, based on the data obtained, of absorbed doses in tumor foci, as well as intact organs and tissues, and effective doses of patients. To date, there are a limited number of studies that provide patient doses for diagnostic examinations using 89Zr-labeled monoclonal antibodies. In this regard, the purpose of this work was to assess the biodistribution of various monoclonal antibodies (ramucirumab, trastuzumab, atezolizumab) labeled with 89Zr, based on published data, with subsequent calculation of absorbed doses in radiosensitive organs and tissues and effective doses of patients. Based on the analysis of experimental data on the biodistribution of monoclonal antibodies labeled with 89Zr for the diagnosis of oncological diseases from the available literature sources and our own assessments, it has been concluded that the results of the determination of absorbed in organs and tissues and effective doses are inconsistent. The absorbed doses in organs, according to different literature sources, vary up to an order of magnitude within one organ and reach 440 mGy per examination, the effective dose varies from 3 to 112 mSv per examination. This may be due to differences in study design, radiometry and dose assessment methods. Comparison with doses obtained on the basis of a general model of biodistribution of monoclonal antibodies demonstrates the possibility of using this model for a rough estimate of internal doses of patients. However, for a more accurate assessment, it is necessary to standardize approaches to the determination of internal radiation doses using the most effective methodological solutions and software products.

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