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Applied Radiation and Isotopes

Silvia Dulanská, Michaela Štofaníková, Ľubomír Mátel, Ivan Novák, Ondrej Šauša, Igor Maťko, Sabína Zvachová
The presented work describes an effective method for 226 Ra determination using laboratory- prepared MnO2 -SiO2 composite resin. Samples were traced with 133 Ba for radium radiochemical recoveries monitoring which were in the range of (77 - 100%). MnO2 - SiO2 composite resin was used to collect for 226 Ra from water samples (pH = 6.5-7.0). Radium was eluted from the column with 50 mL of 4 mol L-1 HNO3 at a flow rate of 1.5 mL min-1 . Alpha-spectrometric counting of Ba(Ra)SO4 microprecipitate was used for 226 Ra determination...
June 26, 2018: Applied Radiation and Isotopes
Daniel R McAlister, E Philip Horwitz
This work presents a complete scheme for the selective separation of actinium and radium isotopes from bulk 232 Th target material, in a process that may be applied in a separation scheme for the production of 225 Ac by proton spallation on thorium. Thorium metal is dissolved in sulfuric acid with small amounts of HF. Actinium and radium are retained on cation exchange resin from the sulfate medium, while neutral and anionic thorium sulfate complexes are rejected. Following rinsing steps to remove residual thorium, actinium and radium are recovered from the cation exchange resin using 5 M HNO3 ...
June 21, 2018: Applied Radiation and Isotopes
Stina Holmgren Rondahl, Henrik Ramebäck
In case of a radiological emergency situation involving e.g. fission of uranium or plutonium, analysis of radioactive strontium will be of importance. The primary radionuclides of interest are 90 Sr, its progeny 90 Y and 89 Sr. A few days following an event, 89 Sr will be the predominant radioisotope of strontium. Most methods found in the literature are valid and applicable when measuring 90 Sr, but when samples contain both 89 Sr/90 Sr interference problematics arise. How these interferences are dealt with will have an effect on the uncertainty of the 90 Sr determination...
June 20, 2018: Applied Radiation and Isotopes
Ivón Oramas Polo, William Souza Santos, Linda V E Caldas
The dosimetric measurements of 147 Pm beta radiation beams have limitations due to their low energy, low dose rate, great dispersion and attenuation in air or tissue. In this work, the Monte Carlo model was developed for a 147 Pm absorbed dose rate determination. This model consists of an extrapolation chamber and a 147 Pm beta radiation source. Moreover, the absorbed dose rate was determined by experimental measurements and the MCNP Monte Carlo code was used. The relative number of particles that crossed the radioactive source window and the particles that crossed the extrapolation chamber entrance window were determined...
June 19, 2018: Applied Radiation and Isotopes
Denis Lamparter, Bernd Hallmann, Heribert Hänscheid, Francesca Boschi, Mario Malinconico, Samuel Samnick
AIM: This work describes a small-scale production of iodine-124 using a 16.5 MeV cyclotron, and a subsequent validation of the formulated sodium [124I]iodide solution for routinely clinical applications. METHODS: Iodine-124 (124 I) was produced via the 124 Te(p, n)124 I reaction using a 16.5 MeV GE PETtrace® cyclotron. Irradiation was performed with a pre-prepared solid target consisting of [124 Te]TeO2 (99.93%) and Al2 O3 . Different layer thicknesses, irradiation and extraction parameters were tested...
June 18, 2018: Applied Radiation and Isotopes
J M Kalita, M L Chithambo
We report the effect of pre-dose on the thermoluminescence (TL) and optically stimulated luminescence (OSL) dose response of α-Al2 O3 :C,Mg and α-Al2 O3 :C. Before any luminescence measurement, the samples were irradiated with different doses, namely 100, 500 and 1000 Gy to populate the deep electron traps. This is the pre-dose. The results from TL and OSL studies are compared with results from samples used without any pre-measurement dose. The TL glow curves and OSL decay curves of α-Al2 O3 :C,Mg recorded after pre-doses of 100, 500 and 1000 Gy are identical to those from a sample used without any pre-dose...
June 15, 2018: Applied Radiation and Isotopes
Tiao Zhao, Liang Li, Zhiqiang Chen
A decomposition model with an iterative solving framework is proposed for use in MeV dual energy computed tomography (DECT). The decomposition model can deal with a broad range of materials and better matches the physics of MeV photons. The proposed iterative solving framework is based on the conventional projection-domain decomposition method, and verified by numerical experiments and experiments. It is shown that images reconstructed with the proposed method have less artifacts and provide more accurate estimates of the atomic number of materials than the conventional projection-domain decomposition method...
June 15, 2018: Applied Radiation and Isotopes
Ivón Oramas Polo, William de Souza Santos, Linda V E Caldas
The absorbed dose rate is the main characterization quantity for beta radiation. The extrapolation chamber is considered the primary standard instrument. To determine absorbed dose rates in beta radiation beams, it is necessary to establish several correction factors. In this work, the correction factors for the backscatter due to the collecting electrode and to the guard ring, and the correction factor for Bremsstrahlung in beta secondary standard radiation beams are presented. For this purpose, the Monte Carlo method was applied...
June 15, 2018: Applied Radiation and Isotopes
H Özdoğan, M Şekerci, I H Sarpün, A Kaplan
The materials used in fusion reactor must be resistance to the harmful effects of radiation in the manner of material itself. Selection of the appropriate materials used in nuclear reactor has a crucial importance to achieve the maximum efficiency and security. Ti, Cu and Zr are known to be employed as first wall materials in fusion reactors. In this study, level density parameter effects on (p,n) and (p,2n) reaction cross-section calculations have been investigated by employing different level density models within TALYS 1...
June 15, 2018: Applied Radiation and Isotopes
Toshioh Fujibuchi, Takatoshi Toyoda, Kento Terasaki
The basic characteristics of three low-cost radiation survey meters using multi-pixel photon counters (MPPC), the C12137, T-GMK2-S, and iMetry, were measured. The linearity of the dose rate was confirmed over the full range of each instrument. All the survey meters could obtain gamma-ray energy spectra, with an accuracy within ± 30% of the theoretical value. These survey meters are therefore applicable for radiation management.
June 15, 2018: Applied Radiation and Isotopes
T Uittenbosch, K Buckley, T Ruth, D M Martinez, C Hoehr
A forced-convection gas target for the production of [11 C]CH4 on a 13 MeV cyclotron was constructed and tested. A small fan was incorporated into the back of the target, which mixes the target gas during irradiation. The effect of the forced convection alone on the target operation and the [11 C]CH4 yield was measured. Forced convection improved the target yield by up to 16 ± 4%. In addition, improvement in heat transfer of up to 70% was observed to be a function of fan speed. Operating with forced convection allowed delivery of 21% higher beam currents while still staying in the acceptable pressure rise during irradiation, providing a 25 ± 7% greater yield...
June 15, 2018: Applied Radiation and Isotopes
T Onishi, H Kumada, K Takada, F Naito, T Kurihara, T Sakae
In boron neutron capture therapy, it is important to evaluate the dose administered to a patient's body outside the tumour area. The exposure dose is evaluated by calculation; however, the calculated value must be validated using a measured value. The dose evaluations based on the measured neutron spectrum are investigated. Multi-foil activation, combined with a LiCaAlF6 scintillation detector and an imaging plate, is proposed as a measurement method. The proposed method can measure the neutron spectrum at various points quickly...
June 11, 2018: Applied Radiation and Isotopes
Guo Xiaofeng, Xiang Qingpei, Tian Dongfeng, Hao Fanhua, Wang Yi, Zhang Yingzeng
Compton imaging is a promising technology for various applications including nuclear safety, nuclear medicine, and astrophysics. For quasi-point-source applications, which are widely found in practice, a novel Compton imaging algorithm incorporating the concept of self-adaption is proposed that provides excellent precision and high efficiency. In particular, this algorithm significantly improves the imaging precision of backward-scattering imaging events so that they can be revived for reconstruction without degrading image quality...
June 7, 2018: Applied Radiation and Isotopes
Yunlong Ge, Wensheng Wu, Duo Dong
In this study, we investigated the feasibility of using a D-Li7 neutron generator to replace a deuterium-tritium (D-T) neutron generator in gas saturation logging. The logging response and gas sensitivity of gas saturation logging based on the inelastic gamma spectrum were simulated with the Monte Carlo method, and the factors that influenced the gas sensitivity and inelastic gamma counts were analyzed based on the spatial response distribution. The results showed that the logging response based on the D-Li7 source was similar to that based on the D-T neutron generator after calibration, which validated the feasibility of this method...
June 6, 2018: Applied Radiation and Isotopes
A Ortiz-Morales, E López-González, G Rueda-Morales, G Ortega-Cervantez, J Ortiz-Lopez
Graphite powder (GP) subjected to microwave radiation (MWG) results in exfoliation of graphite particles into few-layered graphene flakes (GF) intermixed with partially exfoliated graphite particles (PEG). Characterization of MWG by Scanning Electron Microscopy (SEM), Atomic Force Microscopy (AFM) and Raman spectroscopy reveal few-layer GF with sizes ranging from 0.2 to 5 µm. Raman D, G, and 2D (G') bands characteristic of graphitic structures include evidence of the presence of bilayered graphene. The thermoluminescent (TL) dosimetric properties of MWG are evaluated and can be characterized as a gamma-ray sensitive and dose-resistant material with kinetic parameters (activation energy for the main peak located at 400 and 408 K is 0...
June 6, 2018: Applied Radiation and Isotopes
Akanksha Jain, Anupam Mathur, Usha Pandey, Haladhar Dev Sarma, Ashutosh Dash
This work evaluates the potential of a 68 Ga labeled long chain 16C fatty acid for cardiac metabolic imaging. For radiolabeling with 68 Ga, hexadecanedioic acid was coupled with the chelator p-NH2 -Bn-NOTA. Under the optimized conditions, NOTA-hexadecanoic acid could be radiolabeled with 68 Ga in ≥95% yields. In biodistribution studies carried out in Swiss mice, 68 Ga-NOTA-hexadecanoic acid showed low myocardial uptake at 2 min p.i. (3.7 ± 1.3%ID/g). While 68 Ga-NOTA-hexadecanoic acid cleared rapidly from non-target organs such as blood, lungs, intestine and kidney, wash out from liver was slow...
June 5, 2018: Applied Radiation and Isotopes
L Zaidi, M Belgaid, S Taskaev, R Khelifi
The development of a medical facility for boron neutron capture therapy at Budker Institute of Nuclear Physics is under way. The neutron source is based on a tandem accelerator with vacuum insulation and lithium target. The proposed accelerator is conceived to deliver a proton beam around 10 mA at 2.3 MeV proton beam. To deliver a therapeutic beam for treatment of deep-seated tumors a typical Beam Shaping Assembly (BSA) based on the source specifications has been explored. In this article, an optimized BSA based on the 7 Li(p,n)7 Be neutron production reaction is proposed...
May 31, 2018: Applied Radiation and Isotopes
Arijit Ghosh, Karen Woolum, Michael V Knopp, Krishan Kumar
A novel, rapid, and automated loop method for the synthesis of [11 C]nicotine was developed and optimized. The method involves, a reaction of the precursor, (+) nornicotine or (-) nornicotine, with a gas-phase produced [11 C]CH3 I in an 800 µL loop at 75 °C for 5 min followed by a semi-preparatory Reversed-Phase High-Performance Liquid Chromatography (RP-HPLC) purification. The optimized synthesis and purification process was complete in < 30 min and produced [11 C]nicotine with > 99.9% Radiochemical Purity (RCP), no [11 C]CH3 I, no (+) nornicotine, 105 mCi/µmole specific activity, 7...
May 30, 2018: Applied Radiation and Isotopes
Petra Martini, Alessandra Boschi, Gianfranco Cicoria, Federico Zagni, Andrea Corazza, Licia Uccelli, Micòl Pasquali, Gaia Pupillo, Mario Marengo, Massimo Loriggiola, Hanna Skliarova, Liliana Mou, Sara Cisternino, Sara Carturan, Laura Melendez-Alafort, Nikolay M Uzunov, Michele Bello, Carlos Rossi Alvarez, Juan Esposito, Adriano Duatti
In the last years, the technology for producing the important medical radionuclide technetium-99m by cyclotrons has become sufficiently mature to justify its introduction as an alternative source of the starting precursor [99m Tc][TcO4 ]- ubiquitously employed for the production of 99m Tc-radiopharmaceuticals in hospitals. These technologies make use almost exclusively of the nuclear reaction 100 Mo(p,2n)99m Tc that allows direct production of Tc-99m. In this study, it is conjectured that this alternative production route will not replace the current supply chain based on the distribution of 99 Mo/99m Tc generators, but could become a convenient emergency source of Tc-99m only for in-house hospitals equipped with a conventional, low-energy, medical cyclotron...
May 30, 2018: Applied Radiation and Isotopes
Joanna Czub, Dariusz Banaś, Janusz Braziewicz, Iwona Buraczewska, Marian Jaskóła, Urszula Kaźmierczak, Andrzej Korman, Anna Lankoff, Halina Lisowska, Zygmunt Szefliński, Maria Wojewódzka, Andrzej Wójcik
Carbon and oxygen ions were accelerated simultaneously to estimate the effect of irradiation of living cells with the two different ions. This mixed ion beam was used to irradiate the CHO-K1 cells, and a survival test was performed. The type of the effect of the mixed ion beam on the cells was determined with the isobologram method, whereby survival curves for irradiations with individual ion beams were also used. An additive effect of irradiation with the two ions was found.
May 30, 2018: Applied Radiation and Isotopes
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