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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
Hugues Lambert, Timothy Kerry, Clint A Sharrad
The most advanced methodology for the pyroprocessing of spent nuclear fuel is the electrorefining of uranium metal in LiCl-KCl eutectic, in which uranium is solubilized as U(III). The production of U(III) in LiCl-KCl eutectic by the chlorination of uranium metal using BiCl3 has been performed for research purposes. In this work, this reaction was studied in-situ by visual observation, electronic absorption spectroscopy and electrochemistry at 450 °C. The most likely mechanism has been determined to involve the initial direct oxidation of uranium metal by Bi(III) to U(IV)...
2018: Journal of Radioanalytical and Nuclear Chemistry
Małgorzata Pająk, Katarzyna Pałka, Elżbieta Winnicka, Marianna Kańska
This review compiles the combined chemical and enzymatic synthesis of aromatic l-amino acids (l-phenylalanine, l-tyrosine, l-DOPA, l-tryptophan, and their derivatives and precursors) specifically labeled with carbon and hydrogen isotopes, which were elaborated in our research group by the past 20 years. These compounds could be then employed to characterize the mechanisms of enzymatic reactions via kinetic and solvent isotope effects methods.
2018: Journal of Radioanalytical and Nuclear Chemistry
Fredrik Espegren, Henrik Glänneskog, Mark R StJ Foreman, Christian Ekberg
As an emergency action during the Fukushima accident, seawater was used to maintain cooling. To evaluate the effect of the salt on fission-products, sodium chloride, and tellurium were heated together using different ratios in different atmospheres (inert or oxidizing) using thermogravimetric analysis. The experiment under inert conditions showed no indication of interaction. However, under oxidizing conditions an interaction for all samples was observed that prevented an otherwise observed mass increase of the tellurium reference...
2018: Journal of Radioanalytical and Nuclear Chemistry
Maciej Chotkowski
Redox interaction of reduced technetium forms and technetium(VII) with neptunium(III), neptunium(IV) and neptunium(VI) have been investigated using electrochemical and spectroscopic (Vis-NIR) techniques. The neptunium species most stable in 4 M H2 SO4 , i.e. Np(IV) ions, do not reduce Tc(VII) in contrast to Np(VI) ions which oxidize Tc(IV) species to Tc(VII). The interaction of pertechnetates with Np(III) leads to formation of Tc(IV) species. The Vis-NIR measurements showed the generation of intermediate Tc(V) and Np(V) forms during the oxidation of Tc(IV) and competitive reduction of Np(VI)...
2018: Journal of Radioanalytical and Nuclear Chemistry
Mariola Kądziołka-Gaweł, Mateusz Dulski, Lech Kalinowski, Marcin Wojtyniak
Gamma irradiation studies of (Mg0.905 Fe0.095 )2 SiO4 olivine were performed using X-ray fluorescence method, X-ray diffraction, Raman and Mössbauer spectroscopy. The absorbed doses were 300, 600 and 1000 Gy. Small irradiation doses cause an increase of lattice vibrations and small deformation of both M1 and M2 octahedron. The observed effect is similar to the results expose to high temperature. However, the small deformation takes place only in unit cell of Olivine's structure.
2018: Journal of Radioanalytical and Nuclear Chemistry
Nathaly De La Rosa, Per Kristiansson, E J Charlotta Nilsson, Linus Ros, Jan Pallon, Henrik Skogby
Proton-induced reaction (p,α) is one type of nuclear reaction analysis (NRA) suitable especially for light element quantification. In the case of lithium quantification presented in this work, accelerated protons with an energy about of 850 keV were used to induce the 7 Li(p,α)4 He reaction in standard reference and geological samples such as tourmaline and other Li-minerals. It is shown that this technique for lithium quantification allowed for measurement of concentrations down below one ppm. The possibility to relate the lithium content with the boron content in a single analysis was also demonstrated using tourmaline samples, both in absolute concentration and in lateral distribution...
2018: Journal of Radioanalytical and Nuclear Chemistry
Chung Hun Han, Jae Woo Park
This study analyzed the concentrations of potassium, thorium and uranium of the atmospheric PM10 aerosols which were collected at Gosan of Jeju Island during the year of 2014. The mean mass concentration of PM10 was 47.31 μg/m3 . The mean radioactive concentrations of 40 K, 232 Th and 238 U were 7.89, 0.25 and 0.30 μBq/m3 , respectively. The 232 Th/238 U activity concentration ratio of PM10 was 0.830. The 232 Th/238 U ratio during Asian Dust days is 1.073, which is higher than those in other atmospheric conditions...
2018: Journal of Radioanalytical and Nuclear Chemistry
Pavel P Povinec
Recent developments in radiometric and mass spectrometry technologies have been associated in the radiometric sector mainly with underground operations of large volume Ge detectors, while the mass-spectrometry sector, represented mainly by accelerator mass spectrometry and inductively coupled plasma mass spectrometry has become the most sensitive technique for ultra-low-level analyses of long-lived radionuclides. These new developments have had great impact on investigations of rare nuclear processes and applications of radionuclides in environmental, life and space sciences...
2018: Journal of Radioanalytical and Nuclear Chemistry
Daniel Lundberg
The use of replacement lanthanoid ions in actinoid chemistry is commonplace, which requires a full understanding of the similarities and differences between the two series. This overview lists, compares and discusses the available crystallographic data for N -donors for the lanthanoids and the actinoids using their trivalent state as a natural starting point for comparison.
2018: Journal of Radioanalytical and Nuclear Chemistry
H Mohamud, P Ivanov, B C Russell, P H Regan, N I Ward
The effect of competing ions on the sorption behaviour of uranium onto carboxyl-functionalised graphene oxide (COOH-GO) were studied in batch experiments in comparison to graphene oxide (GO) and graphite. The effect of increasing the abundance of select chemical functional groups, such as carboxyl groups, on the selectivity of U sorption was investigated. In the course of the study, COOH-GO demonstrated superior performance as a sorbent material for the selective removal of uranyl ions from aqueous solution with a distribution coefficient of 3...
2018: Journal of Radioanalytical and Nuclear Chemistry
Johannes H Sterba
The main focus for neutron activation analysis (NAA) at the Atominstitut in Vienna has moved to the analysis of archaeological ceramics. The workflow for NAA has been adapted for this material and the elemental spectrum quantified has been expanded for compatibility with international databases. Statistical methods for the grouping of the archaeometric data have been implemented, following the methods applied by Mommsen et al. in Bonn (Archaeometry 30(1):47-57, 1988). Limits of detection specific for ceramics have been calculated and are at the ng/g level...
2018: Journal of Radioanalytical and Nuclear Chemistry
Sandor Demeter, Roman Szweda, Judy Patterson, Marine Grigoryan
Given potential worldwide shortages of fission sourced 99 Mo/99m Tc medical isotopes there is increasing interest in alternate production strategies. A neutron activated 99 Mo source was utilized in a single center phase III open label study comparing 99m Tc, as 99m Tc Methylene Diphosphonate ([99m Tc]Tc-MDP), obtained from solvent generator separation of neutron activation produced 99 Mo, versus nuclear reactor produced 99 Mo (e.g., fission sourced) in oncology patients for which an [99m Tc]Tc-MDP bone scan would normally have been indicated...
2018: Journal of Radioanalytical and Nuclear Chemistry
Agnieszka Dżaluk, Dariusz Malczewski, Jerzy Żaba, Maria Dziurowicz
The natural radioactivities of five characteristic igneous rocks of the eastern foreland of the Opava Mountains (Eastern Sudetes, Poland), obtained in the laboratory and under in situ conditions, are presented. The activity concentrations of 232 Th, 238 U, and 40 K were measured using an HPGe gamma-ray spectrometry system. The ranges of the activity concentrations of 232 Th were 7-71 Bq kg-1 in the laboratory and 6-68 Bq kg-1 for the in situ measurements. For 238 U, the ranges of the activity concentrations were 5-52 Bq kg-1 in the laboratory and 9-48 Bq kg-1 for the in situ measurements, and for 40 K, the ranges were 520-1560 Bq kg-1 in the laboratory and 537-1700 Bq kg-1 for the in situ measurements...
2018: Journal of Radioanalytical and Nuclear Chemistry
L Lakosi, J Zsigrai, A Kocsonya, T C Nguyen, H Ramebäck, T Parsons-Moss, N Gharibyan, K Moody
Low enriched uranium samples of unknown origin were analyzed by 16 laboratories in the context of a Collaborative Materials Exercise (CMX), organized by the Nuclear Forensics International Technical Working Group (ITWG). The purpose was to compare and prioritize nuclear forensic methods and techniques, and to evaluate attribution capabilities among participants. This paper gives a snapshot of the gamma spectrometric capabilities of the participating laboratories and summarizes the results achieved by gamma spectrometry...
2018: Journal of Radioanalytical and Nuclear Chemistry
Stina Holmgren Rondahl, Fabien Pointurier, Linnea Ahlinder, Henrik Ramebäck, Olivier Marie, Brice Ravat, François Delaunay, Emma Young, Ned Blagojevic, James R Hester, Gordon Thorogood, Aubrey N Nelwamondo, Tshepo P Ntsoane, Sarah K Roberts, Kiel S Holliday
This work presents the results for identification of chemical phases obtained by several laboratories as a part of an international nuclear forensic round-robin exercise. In this work powder X-ray diffraction (p-XRD) is regarded as the reference technique. Neutron diffraction produced a superior high-angle diffraction pattern relative to p-XRD. Requiring only small amounts of sample, µ-Raman spectroscopy was used for the first time in this context as a potentially complementary technique to p-XRD. The chemical phases were identified as pure UO2 in two materials, and as a mixture of UO2 , U3 O8 and an intermediate species U3 O7 in the third material...
2018: Journal of Radioanalytical and Nuclear Chemistry
Anthony D Appelhans, John E Olson, David A Dahl, Michal B Ward, Troy A Robinson, James E Delmore
A new isotope separator has been designed, constructed, and put into routine operation for separation of 133 Xe providing a major advancement and significant cost reduction in preparation of this radioactive isotope. The design features and advantages are discussed that expedite high purity separation of relatively small quantities of this isotope. These advantages could be easily used to expedite separation of other shorter-lived radioactive isotopes.
2018: Journal of Radioanalytical and Nuclear Chemistry
Rolf Zeisler, Hana Cho, Iberê Souza Ribeiro Junior, Martin G Shetty, Danyal Turkoglu
A new γγ coincidence system has been set up at NIST. It is operated with a digital data finder supported by new software developed at NIST. The system is used to explore possible enhancements in instrumental neutron activation analysis (INAA) and study applicability to neutron capture prompt gamma activation analysis (PGAA). The performance of the system is tested with certified reference materials for efficiency calibration and quantitative performance. Comparisons of INAA results based on conventional gamma-ray spectrometry data with INAA results based on coincidence data obtained from the same samples show improvements in the counting uncertainties and demonstrates the quantitative accuracy of the new system...
October 2017: Journal of Radioanalytical and Nuclear Chemistry
Rick L Paul
A combination of cold neutron prompt gamma-ray activation analysis (CNPGAA) and thermal neutron (TN) PGAA was used to determine sulfur in fuel oils to develop a method to provide values for certification. CNPGAA was used to measure S/H mass ratios, and TNPGAA to measure hydrogen mass fractions. Measurements were combined to determine sulfur mass fractions (with expanded uncertainties) of 2.159 % ± 0.072 % for SRM 1622e, 0.7066 % ± 0.0120 % for SRM 1619b, and 0.1266 % ± 0.0030 % for SRM 1617b, in agreement with certified values...
February 2017: Journal of Radioanalytical and Nuclear Chemistry
Richard M Lindstrom
Nearly fifty years ago, two landmark papers appeared that should have cured the problem of ambiguous uncertainty statements in published data. Eisenhart's paper in Science called for statistically meaningful numbers, and Currie's Analytical Chemistry paper revealed the wide range in common definitions of detection limit. Confusion and worse can result when uncertainties are misinterpreted or ignored. The recent stories of cold fusion, variable radioactive decay, and piezonuclear reactions provide cautionary examples in which prior probability has been neglected...
February 2017: Journal of Radioanalytical and Nuclear Chemistry
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