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Applied Radiation and Isotopes

Tobias Hollmer, Winfried Petry
(99)Mo is the most widely used radioactive isotope in nuclear medicine. Its main production route is the fission of uranium. A major challenge for a reliable supply is the conversion from highly enriched uranium (HEU) to low enriched uranium (LEU). A promising candidate to realize this conversion is the cylindrical LEU irradiation target. The target consists of a uranium foil encapsulated between two coaxial aluminum cladding cylinders. This target allows a separate processing of the irradiated uranium foil and the cladding when recovering the (99)Mo...
October 6, 2016: Applied Radiation and Isotopes
Petra Martini, Alessandra Boschi, Gianfranco Cicoria, Licia Uccelli, Micòl Pasquali, Adriano Duatti, Gaia Pupillo, Mario Marengo, Massimo Loriggiola, Juan Esposito
The design and fabrication of a fully-automated, remotely controlled module for the extraction and purification of technetium-99m (Tc-99m), produced by proton bombardment of enriched Mo-100 molybdenum metallic targets in a low-energy medical cyclotron, is here described. After dissolution of the irradiated solid target in hydrogen peroxide, Tc-99m was obtained under the chemical form of (99m)TcO4(-), in high radionuclidic and radiochemical purity, by solvent extraction with methyl ethyl ketone (MEK). The extraction process was accomplished inside a glass column-shaped vial especially designed to allow for an easy automation of the whole procedure...
October 5, 2016: Applied Radiation and Isotopes
Martin Schulc, Petr Baroň, Evžen Novák, Bohumil Jánský, Davit Harutyunyan
The presented paper aims to compare various measured neutron induced reaction rates in Aluminium with computed ones in different nuclear data libraries. A (252)Cf neutron source with emission rate of 9.53E8 n/s was used. Reactions involved in the study were (27)Al(n,g), (27)Al (n,p) and (27)Al (n,α).
October 4, 2016: Applied Radiation and Isotopes
Yukihisa Sanada, Tadashi Orita, Tatsuo Torii
Aerial radiological survey using an unmanned aerial vehicle (UAV) was applied to measurement surface contamination around the Fukushima Daiichi nuclear power station (FDNPS). An unmanned helicopter monitoring system (UHMS) was developed to survey the environmental effect of radioactive cesium scattered as a result of the FDNPS accident. The UHMS was used to monitor the area surrounding the FDNPS six times from 2012 to 2015. Quantitative changes in the radioactivity distribution trend were revealed from the results of these monitoring runs...
October 3, 2016: Applied Radiation and Isotopes
C Duchemin, A Guertin, F Haddad, N Michel, V Métivier
Several terbium isotopes are suited for diagnosis or therapy in nuclear medicine. Tb-155 is of interest for SPECT imaging and/or Auger therapy. High radionuclide purity is mandatory for many applications in medicine. The quantification of the activity of the produced contaminants is therefore as important as that of the radionuclide of interest. The experiments performed at the ARRONAX cyclotron (Nantes, France), using the deuteron beam delivered up to 34MeV, provide an additional measurement of the excitation function of the Gd-nat(d,x)Tb-155 reaction and of the produced terbium and gadolinium contaminants...
September 30, 2016: Applied Radiation and Isotopes
F Ditrói, S Takács, H Haba, Y Komori, M Aikawa
Cross sections of alpha particle induced nuclear reactions have been measured on thin natural cadmium targets foils in the energy range from 11 to 51.2MeV. This work was a part of our systematic study on excitation functions of light ion induced nuclear reactions on different target materials. Regarding the cross sections, the alpha induced reactions are not deeply enough investigated. Some of the produced isotopes are of medical interest, others have application in research and industry. The radioisotope (117m)Sn is a very important theranostic (therapeutic + diagnostic) radioisotope, so special care was taken to the results for that isotope...
September 30, 2016: Applied Radiation and Isotopes
Bakhtiar Azadbakht, Hossein Afarideh, Mohammad Ghannadi-Maragheh, Mehdi Asgari, Ali Bahrami-Samani
In this study, a simple electrochemical procedure adaptable for using low specific activity (188)W for separation and purification of (188)Re from (188)W to obtain no carrier added (NCA) (188)Re is developed. The electrochemical parameters were optimized to maximize the (188)Re electrodeposition yield with minimal (188)W contamination. Two cycle electrolysis procedure was developed. The first electrochemical cell was used for separation of (188)Re and in the second electrochemical cell, separation and purification of (188)Re with >90% deposition yield of (188)Re and minimal contamination of (188)W (<10(-4)%) was achieved...
September 28, 2016: Applied Radiation and Isotopes
Yaser Kasesaz, Marjan Karimi
In order to use 14.1MeV neutrons produced by d-T neutron generators, two special and novel Beam Shaping Assemblies (BSA), including multi-layer and hexagonal lattice have been suggested and the effect of them has been investigated by MCNP4C Monte Carlo code. The results show that the proposed BSA can provide the qualified epithermal neutron beam for BNCT. The final epithermal neutron flux is about 6e9 n/cm2.s. The final proposed BSA has some different advantages: 1) it consists of usual and well-known materials (Pb, Al, Fluental and Cd); 2) it has a simple geometry; 3) it does not need any additional gamma filter; 4) it can provide high flux of epithermal neutrons...
September 28, 2016: Applied Radiation and Isotopes
Rajesh Chakraborty, Sandipan Sarkar, Siddhartha Pal, Pabitra Chattopadhyay
A new ion-exchanger having chemical formula [Me2NH2]3[Mo12O40S] and belonging to the class of Keggin type polyoxometalate was synthesized and characterized by single-crystal X-ray structure determination. The crystal of the exchanger is rhombohedral, space group R-3 with cell dimensions, a =16.504(18) Å, b =16.504(18)Å (1) Å, c =25.23(3)Å and α=90.00°, β=90.00°, γ=120.00° and Z =6, 3.284gcm(-3). The compound behaves as an ion-exchanger and it is significantly stable towards thermal, chemical environments and total radiation dose of 35...
September 28, 2016: Applied Radiation and Isotopes
Yu Tang, Shuntao Li, Yuanyou Yang, Wen Chen, Hongyuan Wei, Guanquan Wang, Jijun Yang, Jiali Liao, Shunzhong Luo, Ning Liu
A simple and convenient method for radiochemical separation (89)Zr with no harmful substance was explored. The separated (89)Zr was found to be [(89)Zr]Zr-chloride, and the recovery of the radioactivity was 85%±3% with high radionuclidic purity (99.99%). The yields of (89)Zr via the reaction of (p, n) or (d, 2n) on Y target were also evaluated on CS-30 cyclotron, indicating the latter was more favorable for the production of (89)Zr with a yield of 58±4 MBq/μA·h.
September 26, 2016: Applied Radiation and Isotopes
S M Golgoun, D Sardari, M Sadeghi, F Babapour Mofrad
This study focuses on investigating a new model of combined backscatter and transmission method for nuclear densitometer. In this method for density measurement, a true combination of transmission and backscatter methods was studied and related equations were developed. The MCNP4C code was used for simulation of this combined detector model (CDM) and by applying theoretical calculations, density equation was corrected for the proposed nuclear densitometer. In the new method presented here, the buildup effect was estimated by an online system that was improved in our laboratory and was replaced by a new conceptual calculation...
September 22, 2016: Applied Radiation and Isotopes
O A El-Kawy, J A García-Horsman, R K Tuominen
(99m)Tc-tricarbonyl-vardenafil was specifically radiosynthesized for diagnostic evaluation of erectile dysfunction with a radiochemical yield ~97.2%. It was stable in saline up to 15h and in serum for more than 6h. The radiocomplex was lipophilic with a partition coefficient ~1.32 and plasma protein binding 72-76%. Its structure was determined using molecular mechanics and confirmed by NMR. In-silico docking to its target PDE5 enzyme was performed. The radiocomplex inhibitory activity was assessed and its IC50 was 0...
September 21, 2016: Applied Radiation and Isotopes
V Giménez-Alventosa, F Ballester, J Vijande
The design and construction of geometries for Monte Carlo calculations is an error-prone, time-consuming, and complex step in simulations describing particle interactions and transport in the field of medical physics. The software VoxelMages has been developed to help the user in this task. It allows to design complex geometries and to process DICOM image files for simulations with the general-purpose Monte Carlo code PENELOPE in an easy and straightforward way. VoxelMages also allows to import DICOM-RT structure contour information as delivered by a treatment planning system...
September 21, 2016: Applied Radiation and Isotopes
Liviu Mateescu, N Prasad Kadambi, Nuggehalli M Ravindra
Monte Carlo methods, in their direct brute simulation incarnation, bring realistic results if the involved probabilities, be they geometrical or otherwise, remain constant for the duration of the simulation. However, there are physical setups where the evolution of the simulation represents a modification of the simulated system itself. Chief among such evolving simulated systems are the activation/transmutation setups. That is, the simulation starts with a given set of probabilities, which are determined by the geometry of the system, the components and by the microscopic interaction cross-sections...
September 21, 2016: Applied Radiation and Isotopes
W C M Viana, D Lambertz, E S Borges, A M O Neto, K M F T Lambertz, A Amaral
Among the radiotherapeutics' modalities, total body irradiation (TBI) is used as treatment for certain hematological, oncological and immunological diseases. The aim of this study was to evaluate the long-term effects of low-dose TBI on plasma concentration of total protein and albumin using prematurely and undernourished rats as animal model. For this, four groups with 9 animals each were formed: Normal nourished (N); Malnourished (M); Irradiated Normal nourished (IN); Irradiated Malnourished (IM). At the age of 28 days, rats of the IN and IM groups underwent total body gamma irradiation with a source of cobalt-60...
September 20, 2016: Applied Radiation and Isotopes
Mushtaq Abed Al-Jubbori
An empirical relationship describing the bulk etch rate is formulated. The equation involves two free fitting parameters, which reproduce the bulk etch rate for CR-39 by alpha particles at different normalities of the etching solution. The values of the fitting parameters were obtained from the experimental data. This relationship is used to predict the bulk etch rate at different normalities.
September 20, 2016: Applied Radiation and Isotopes
Yixin Liu, Biao Wei, Renhong Zhuo, Dezhi Wen, Dajie Ding, Yang Xu, Benjiang Mao
To develop mobile calibration equipment for gamma-ray dose or dose rate meters in the field of radiation protection, a minitype reference radiation (MRR) of 0.5m×0.5m×0.5m cube was set up and used for investigation. Two types, which add up to 12 daily used gamma-ray dose rate meters, were used as samples to determine the conventional true value of air kerma (CAK) at the point of test in the MRR. A gamma-ray spectrometer was also used to monitor the scattering gamma rays in the MRR, which were applied further to characterize the disturbance of scattering gamma ray in CAK determination...
September 15, 2016: Applied Radiation and Isotopes
Frédéric Juget, Youcef Nedjadi, Thierry Buchillier, François Bochud, Claude Bailat
The half-life of (137)Cs was measured with an ionization chamber by following the decay of 5 sources over a 30 years period between 1983 and 2013. The ratio between the ionization chamber current for the cesium sources and (226)Ra source was used for the half-life calculation. The value found for the (137)Cs half-life is 10,955.2±10.7 days, where the uncertainty evaluation combines type A and B for one standard deviation.
September 15, 2016: Applied Radiation and Isotopes
Valentina S Yakovleva, Petr M Nagorsky, Maksim S Cherepnev, Alla G Kondratyeva, Kseniya S Ryabkina
Results of experimental and theoretical studies of the responses of the β- and γ-radiation fields in the surface atmosphere to precipitation are presented. Most of the bursts of the β-radiation flux density and γ-radiation dose rate were found to coincide with periods of precipitation. However, the magnitude of bursts does not always correlate with the intensity of the precipitation. The following aspects were analyzed: the total duration of recorded bursts, the durations of the rises and recessions of the bursts, the form of the bursts and the dependence of the magnitude of the bursts on the altitude of the detector position...
September 14, 2016: Applied Radiation and Isotopes
E Cuesta, R L Lozano, E G San Miguel, M Casas-Ruiz, J P Bolívar
This paper relates the calibration of a low background gas-flow proportional counter. This calibration has been used to determine low activity of (234)Th in coastal water samples. Two methods were used to prepare calibration samples: Evaporation and Electrodeposition. First method was rejected due to the lack of reproducibility because the different geometry adopted by the drops of tracer once dried on the disk. On the contrary, through the second method, similar efficiencies were obtained in all detectors with an average of 0...
September 13, 2016: Applied Radiation and Isotopes
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