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Journal of Radioanalytical and Nuclear Chemistry

Kevin B Lavelle, Richard M Essex, Kevin P Carney, Jeffrey T Cessna, Cole R Hexel
A new nuclear forensic reference material has been characterized as a standard for radiochronometric determination of the model purification date for 137 Cs sources. The purification date of a radioactive source is a potentially diagnostic nuclear forensic signature for determining the provenance of a radioactive material. Reference values have been measured for the attributes needed to use the 137 Cs/137 Ba chronometer: the molality (reported here as nmol g-1 ) of 137 Cs and of the radiogenic portion of 137 Ba in the material (hereafter referred to as 137 Ba*)...
2018: Journal of Radioanalytical and Nuclear Chemistry
Ryan Fitzgerald, Leticia Pibida
Protactinium-233 (233 Pa) is used as a tracer for radiochemical analysis and is of particular interest as an isotope dilution mass spectrometry (IDMS) spike for 231 Pa/235 U radio-chronometry. To this end, we present massic activity determinations by two methods for a 233 Pa solution, which was prepared at Lawrence Livermore National Laboratory (LLNL) and is being characterized at multiple labs as part of a 231 Pa reference material production project. One activity determination method was 4π β - γ anti-coincidence counting in a multi-dimensional extrapolation model, with Monte Carlo corrections...
2018: Journal of Radioanalytical and Nuclear Chemistry
Richard M Essex, Jacqueline L Mann, Ronald Collé, Lizbeth Laureano-Perez, Megan E Bennett, Heather Dion, Ryan Fitzgerald, Amy M Gaffney, Alkiviadis Gourgiotis, Amélie Hubert, Kenneth G W Inn, William S Kinman, Stephen P Lamont, Robert Steiner, Ross W Williams
A new determination of the 229 Th half-life was made based on measurements of the 229 Th massic activity of a high-purity solution for which the 229 Th molality had previously been measured. The 229 Th massic activity was measured by direct comparison with SRM 4328C using 4παβ liquid scintillation counting, NaI counting, and standard addition liquid scintillation counting. The massic activity was confirmed by isotope dilution alpha spectrometry measurements. The calculated 229 Th half-life is (7825 ± 87) years ( k = 2), which is shorter than the three most recent half-life determinations but is consistent with these values within uncertainties...
2018: Journal of Radioanalytical and Nuclear Chemistry
Alan Dyer, Joe Hriljac, Nick Evans, Ian Stokes, Peter Rand, Simon Kellet, Risto Harjula, Teresia Moller, Zoe Maher, Ross Heatlie-Branson, Jonathan Austin, Scott Williamson-Owens, Manon Higgins-Bos, Kurt Smith, Luke O'Brien, Nick Smith, Nick Bryan
Mud Hills clinoptilolite has been used in an effluent treatment plant (SIXEP) at the Sellafield nuclear reprocessing site. This material has been used to remove 134/137 Cs and 90 Sr successfully from effluents for 3 decades. Samples of the zeolite have been tested in column experiments to determine their ability to remove radioactive Cs+ and Sr2+ ions under increasing concentrations of competing ions, Ca2+ , Mg2+ , Na+ and K+ . These ions caused increased elution of Cs+ and Sr2+ . Ca2+ , Mg2+ and K+ were more effective competitors than Na+ ...
2018: Journal of Radioanalytical and Nuclear Chemistry
J W Mietelski, Jolanta Wojtycza, Marek Zalewski, Jacek Kapała, Ewa Tomankiewicz, Paweł Gaca
Presented are results on the Pu and Th isotopes activity concentration found in the upper part of bottom sediments collected from a deep part of 29 lakes in N-E Poland by diving in 2000. Analyses of Pu isotopic ratios allowed for the discussion of Pu origin. Maximum percentage of 239+240 Pu activity from Chernobyl fallout was 24%. Surface deposition of 239+240 Pu was calculated. No relationship was found between the plutonium and main chemical matrix components of sample nor with the trophic status of the lake...
2018: Journal of Radioanalytical and Nuclear Chemistry
Noémi M Nagy, József Kónya
The sorption of phosphate on soils is studied by radioisotopic tracer method. Two consecutive processes with rather different rates were differentiated: namely the heterogeneous isotope exchange between the phosphate in the soil solution and the weakly sorbed phosphate (fast reaction), and the transformation of weakly sorbed phosphate to tightly sorbed phosphate (slow reaction). In this paper, it is shown how the rate constants of these two processes can be determined by a radiotracer with a relatively short half-life...
2018: Journal of Radioanalytical and Nuclear Chemistry
Yuichiro Kumamoto, Michio Aoyama, Yasunori Hamajima, Eitarou Oka, Akihiko Murata
In 2015-2017, we measured activity concentration of radiocesium in the western subtropical gyre of the North Pacific Ocean and revealed the time evolution of radiocesium derived from the Fukushima Dai-ichi Nuclear Power Plant (FNPP1) accident between 2011 and 2017. The FNPP1-derived radiocesium deposited on the area south of the Kuroshio/Kuroshio Extension Currents in March 2011 was transported southward and westward through subsurface layers due to subduction of the subtropical mode water. In 2014, the radiocesium in the subsurface layers returned to the north and circulated within the Kuroshio recirculation area...
2018: Journal of Radioanalytical and Nuclear Chemistry
Christian Ekberg, Diogo Ribeiro Costa, Marcus Hedberg, Mikael Jolkkonen
Nuclear energy has been a part of the energy mix in many countries for decades. Today in principle all power producing reactors use the same techniqe. Either PWR or BWR fuelled with oxide fuels. This choice of fuel is not self evident and today there are suggestions to change to fuels which may be safer and more economical and also used in e.g. Gen IV nuclear power systems. One such fuel type is the nitrides. The nitrides have a better thermal conductivity than the oxides and a similar melting point and are thus have larger safety margins to melting during operation...
2018: Journal of Radioanalytical and Nuclear Chemistry
Tomoko M Nakanishi
Since plants live on inorganic elements, absorbing ions from roots and transferring them to each tissue in a plant is an essential activity. However, little is known about the movement of the elements or water in plant tissue. Though fluorescent imaging is now overwhelmingly used at the microscopic level in biology, especially to visualize chemicals or organelles in a cell, radioisotope imaging has become one of the important methods for human imaging in the medical field. In the case of plant studies, however, real-time radioisotope imaging is little-known among plant researchers...
2018: Journal of Radioanalytical and Nuclear Chemistry
Y Inomata, M Aoyama, T Tsubono, D Tsumune, Y Kumamoto, H Nagai, T Yamagata, M Kajino, Y T Tanaka, T T Sekiyama, E Oka, M Yamada
Distributions of radiocaesium (134 Cs and 137 Cs) derived from the Tokyo Electric Power Company (TEPCO) Fukushima Dai-ichi Nuclear Power Plant (FNPP1) accident in the North Pacific Ocean in the summer of 2012 were investigated. We have estimated the radiocaesium inventory in the surface layer using the optimal interpolation analysis and the subducted amount into the central mode water (CMW) by using vertical profiles of FNPP1-134 Cs and mass balance analysis as the first approach. The inventory of the 134 Cs in the surface layer in the North Pacific Ocean in August-December 2012 was estimated at 5...
2018: Journal of Radioanalytical and Nuclear Chemistry
Zsolt Varga, Adrian Nicholl, Erich Hrnecek, Maria Wallenius, Klaus Mayer
The paper describes the age (production date) determination of uranium reference materials using the 231 Pa/235 U ratio. Direct addition of 237 Np in secular equilibrium with its 233 Pa daughter was chosen instead of the regular milking of 237 Np to avoid possible loss of Pa. Sample preparation consists of a fast, one-step procedure. The developed method using ICP-MS for the measurement of 231 Pa is more precise than alpha spectrometry and is applicable for freshly produced low-enriched uranium materials. The measured ages are in good agreement with the reported production dates, thus the 231 Pa/235 U chronometer can be applied for validation of 230 Th/234 U in nuclear forensics and safeguards...
2018: Journal of Radioanalytical and Nuclear Chemistry
Michio Aoyama
Long range transport of radiocaesium derived from local fallout occurred early 1950s, global fallout which occurred mainly late 1950s and early 1960s and the Fukushima accident occurred in 2011 were investigated and presented for ocean surface in the Pacific Ocean. HAM database and its update were used in this study to present whole history of radioccaesium transport in surface layer in the interested region. Since both the main local/global fallout regions and injection of radiocaesium by Fukushima accident occurred in the western North Pacific and constrain of surface current systems which governed surface transport processes were subtropical gyre and subarctic gyre, radiocaesium transport in surface water in the mid latitude was characterized as rapid eastward transport along Kuroshio and Kuroshio extension...
2018: Journal of Radioanalytical and Nuclear Chemistry
Katarzyna M Szufa, Jerzy W Mietelski, Robert Anczkiewicz, Dariusz Sala, Maria A Olech
The aim of the article was to verify the hypothesis concerning the diversification of plutonium sources in the natural environment of Antarctica. Plutonium activity and atom ratios were analyzed in two groups of biological samples: terrestrial and marine. Both isotopic ratios in the terrestrial set were consistent with global radioactive fallout ratios. The average activity ratio in the marine ecosystem was lower than global radioactive fallout. At the same time mass ratio values in this group turned out to be surprisingly varied...
2018: Journal of Radioanalytical and Nuclear Chemistry
Paweł Grabowski, Przemysław Jarosiński, Piotr Szajerski, Hanna Gwardiak
The objective was to study changes in water-saturated biodiesel irradiated by electron beam and to analyse them considering the influence of absorbed dose. Based on obtained results it can be concluded that irradiation did not affect ester groups in FAME molecules, but strongly influenced on double bonds. Total ester content decreased linearly with the increase in absorbed dose, causing FAME not to meet the requirement of PN-EN 14214 concerning the ester content (96.5 wt%). Therefore, the use of ionizing radiation to improve biodiesel properties is unlikely, but it is worth to consider electron beam sterilisation of this biofuel...
2018: Journal of Radioanalytical and Nuclear Chemistry
Tomasz Mróz, Kamil Brudecki, Jerzy W Mietelski, Mirosław Bartyzel, Ryszard Misiak, Andrzej Kornas
It is well known that monitoring of radioactivity released from nuclear medicine departments is necessary to ensure the radiological safety of patients and personnel. Unfortunately, equipment for air sampling is often expensive, loud and is not suitable to use in hospitals. Our goal was to find cheap and simple system for passive monitoring of 131 I activity concentration in the air of nuclear medicine departments. Medical activated charcoal tablets were used, because charcoal is excellent material for 131 I trapping and tablets are readily available...
2018: Journal of Radioanalytical and Nuclear Chemistry
Ryohei Sugita, Natsuko I Kobayashi, Keitaro Tanoi, Tomoko M Nakanishi
Using the real-time radioisotope imaging system (RRIS), we present the carbon dioxide gas fixation process of a soybean plant applying the 14 C-labeled gas. When 14 CO2 gas was supplied to the selected mature leaf, the fixed carbon, photosynthate, was transferred and accumulated to the younger leaves preferentially within 24 h. When 14 CO2 gas was supplied to the younger leaves, fixed carbon was hardly moved. In the case of the pods, fixed 14 CO2 gas in the leaf was preferentially transferred to the closest pod...
2018: Journal of Radioanalytical and Nuclear Chemistry
Dorian Zok, Johannes H Sterba, Georg Steinhauser
Related to the recent nuclear release of radioactive ruthenium isotopes in fall 2017, we analyzed air filters from Vienna for irregularities in the (stable) elemental composition of particulate matter from this period. Methods were SEM/EDXS and INAA. For comparison, a reference filter from 2007 and blank filters were used. The chemical fingerprint encompassed 28 elements. The results show no indication for a considerable change in the elemental composition of the suspended matter. For example, no anomalies in the abundance of platinum group elements were found...
2018: Journal of Radioanalytical and Nuclear Chemistry
Johannes H Sterba, Hannes Sperrer, Florian Wallenko, Jan M Welch
The Sr and Cs adsorption capacities of LithoFill™, LithoGran™ and a competing clinoptilolite containing zeolite product were investigated by radioanalytical methods (85 Sr and 134 Cs gamma spectroscopy). The dependence of adsorption and adsorption rate on physical factors including temperature, available ions and time were assessed. In addition, the reversibility of adsorption under high ionic strength conditions was also examined. In general, cesium is more strongly adsorbed than strontium, adsorption yields are generally independent of temperature (from room temperature to 65 °C) and adsorption is relatively rapid (identical results for 2 or 5 day adsorption times)...
2018: Journal of Radioanalytical and Nuclear Chemistry
Ian Hoffman, Rodney Berg
The Comprehensive Nuclear-Test-Ban Treaty (CTBT) bans the testing of nuclear explosive devices underground, in the atmosphere and underwater. Two main technologies, radionuclide and seismo-acoustic monitoring, are deployed in the International Monitoring System used for the verification of the CTBT. Medical isotope production from fission-based processes is the dominant contributor to a worldwide background of radioxenon. This background can make the discrimination of nuclear tests from legitimate nuclear activities very challenging...
2018: Journal of Radioanalytical and Nuclear Chemistry
Manikandan Kadirvel, Déborah Cardoso, Sally Freeman, Gavin Brown
N -Methyl carbamoylimidazole is a safe and practical alternative to methyl isocyanate for carbamoylation reactions. We have developed a new chemical route for its synthesis from methyl iodide and applied this to the synthesis of N -[11 C]methyl carbamoylimidazole as a new [11 C]synthon to radiolabel biomolecules for PET imaging research. N -[11 C]methyl carbamoylimidazole was prepared from [11 C]methyl iodide in 70-74% radiochemical yield (decay corrected) and can be used in situ for further reaction without purification...
2018: Journal of Radioanalytical and Nuclear Chemistry
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