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Applied Radiation and Isotopes

Zahra Karimi, Mahdi Sadeghi, Malihe Rostampour
Zinc-65 has been of great interest in medical, biomedical, agricultural, and industrial applications due to its suitable half-life and decay properties. The 65 Zn was produced via neutron irradiation on natural zinc oxide and natural zinc oxide nanoparticles targets in Tehran Research Reactor (TRR) at a thermal neutron flux of 4.5 × 1013 n cm-2 s-1 for 30 min. The excitation function of 64 Zn(n,γ)65 Zn reaction was calculated via the TALYS-1.8 code. The MCNPX code was used to calculate the thermal neutron distribution...
September 5, 2018: Applied Radiation and Isotopes
Jun Hirouchi, Yukiyasu Nishizawa, Yoshimi Urabe, Kazumasa Shimada, Yukihisa Sanada, Masahiro Munakata
The influence of gamma-rays from natural nuclides (particularly the radon progenies, 214 Pb and 214 Bi) must be excluded from aerial radiation monitoring (ARM) data to accurately estimate the deposition of artificial radionuclides. A method for discriminating the influence of the radon progenies in air from the ARM data was developed. Two types of detectors with different crystal sizes were installed in a helicopter. The gamma-ray responses of these detectors were simulated using EGS5. The influence of the radon progenies in air was excluded using the relation between the count rates of six NaI (Tl) detectors and a LaBr3 detector...
September 1, 2018: Applied Radiation and Isotopes
Jin Wang, Yingying Zhang, Dongyan Liu, Bingwei Wu, Ying Zhang, Husen Jiang
The NaI(Tl) detector has become the main way of research and application of in-situ radioactivity measurement in the marine environment due to many advantages on detection efficiency, power consumption, cost and applicability. But for the poor energy resolution and there is a high background in the low energy region of the spectrum measured mainly originating from the Compton scattering of natural radionuclides such as 40 K with high concentrations in seawater, it is difficult and also an interesting topic for NaI(Tl) detector to identificate the radionuclides and calculate them in seawater by analyzing the spectra measured...
September 1, 2018: Applied Radiation and Isotopes
M Topaksu, V Correcher, C Boronat, J Garcia-Guinea, Z G Portakal, S Akça
This work reports on the cathodoluminescence (CL) and thermoluminescence (TL) properties of gem-quality diaspore samples from Milas/Muğla (Turkey) after 100 h of ultraviolet-C (UVC) exposure. The UVC exposure induces significant changes in the intensity of the CL emission in the range of 400-800 nm that would be mainly associated with photo-oxidation processes of the impurities (Cr3+ , Ti3+ , Fe2+ ) that substitute for Al3+ in the diaspore (α-AlOOH) lattice. The UVC effect on the 400 nm-TL behavior of beta irradiated samples in the range of 0...
September 1, 2018: Applied Radiation and Isotopes
Ş Turhan, K Demir, M Karataşlı
In this study, clay brick (CBRICK) and pumice brick (PBRICK) samples used as structural material in the construction of dwellings, schools, workplaces and factories in Turkey were compared with each other from a radiological viewpoint. The activity concentrations of 226 Ra, 232 Th and 40 K naturally occurring in CBRICK and PBRICK samples collected from different regions of Turkey were determined by using a gamma-ray spectrometer with a high purity germanium detector (HPGe). The average activity concentrations of 226 Ra, 232 Th and 40 K in CBRICK and PBRICK samples were found as 35...
August 30, 2018: Applied Radiation and Isotopes
Verena Pichler, Chrysoula Vraka, Neydher Berroterán-Infante, Andreas Krcal, Harald Eidherr, Tatjana Traub-Weidinger, Marcus Hacker, Markus Mitterhauser, Wolfgang Wadsak
Radiosynthetic optimization is crucial in routine PET production but is often neglected in literature. Small changes in the radiochemical procedure can increase the yield significantly and reduce time fluctuation within the synthetic procedure enabling better planning and product release on time. Therefore, a highly reproducible production method for L-[S-methyl-11 C]methionine is presented, which uses a fully automated GE TRACERlab FX C Pro synthesizer. Evolution of the synthetic procedure lead to a protocol with a nearly doubled absolute yield...
August 29, 2018: Applied Radiation and Isotopes
Mark A Moore, Robert M Counce, Jack S Watson, Howard Hall
The performance of two inorganic ion exchange resins, Isolute SCX and Isolute SCX-2, were compared to the performance of the organic resin AG-50X8 in the separation of the radionuclide bismuth-213 from its parent solution of actinium-225. The breakthrough of the actinium-225 for all three columns was well below the toxicity level but the Isolute SCX and Isolute SCX-2 produced less of the bismuth-213 available on the column.
August 25, 2018: Applied Radiation and Isotopes
Mahdi Seifi Moradi, Babak Shirani Bidabadi
A large number of nuclear medicine radionuclides are Auger-electron-emitters and internal conversion electrons which can transmit significant doses to the patient during diagnosis. Therefore, the dosimetry of these radioisotopes is necessary for the evaluation of their biological effects and their use for treatment and targeted-radiotherapy. In this study, dosimetry calculation of a number of widely used radioisotopes in nuclear medicine was performed on a cellular scale using Geant4-DNA simulation. S-values of some of the diagnostic radioisotopes, including 123 I, 125 I, 99m Tc, 67 Ga, 201 Tl, and 111 In, were evaluated in a homogeneous spherical geometry model with unit density in which the cell and nucleus were concentric...
August 24, 2018: Applied Radiation and Isotopes
J Bayón, L Alejo, C Koren, C Huerga, E Corredoira, A Serrada, E Balbacid, F Gutierrez-Larraya, E Guibelalde
This paper presents a fast method to estimate the annual eye lens dose levels for interventional practitioners applying the Monte Carlo method of uncertainty assessment. The estimation was performed by placing an anthropomorphic phantom in the typical working position, and applying the habitually employed protocol. No radiation protection devices were considered in the simulation. The results were compatible with the measurements performed during interventions by placing dosimeters in the vicinity of the eyes of two paediatric interventional cardiologists working with a fluoroscopic biplane system...
August 23, 2018: Applied Radiation and Isotopes
Andrew Tillett, Larry Benninger, John Dermigny, Christian Iliadis
We present the performance of a γγ-coincidence spectrometer for measuring the activities of thorium and uranium daughters in environmental samples. The spectrometer consists of two NaI(Tl) detectors facing each other inside a low-background passive shield. We present coincidence gating schemes for achieving the best signal-to-noise ratios, coincidence detection efficiencies, background levels, and minimum detectable activities. The spectrometer is simulated using Geant4 to correct sample efficiencies for self-absorption effects...
August 23, 2018: Applied Radiation and Isotopes
Vusani Mandiwana, Lonji Kalombo, Anne Grobler, Jan Rijn Zeevaart
The aim of this study was to establish the in vivo uptake and tissue distribution of 99m Tc-MDP-encapsulated Solid Lipid Nanoparticles (SLNs) post administration. Radioactive 99m Tc-MDP encapsulated into SLNs was administered to rats to trace their biodistribution through imaging and ex vivo studies. As expected IV injected 99m Tc-MDP exhibited predominant visual bone uptake and a high localisation of particles in the kidneys (3.87%ID/g) followed by bone (2.66%ID/g). IV administered 99m Tc-MDP encapsulated by SLN showed similar uptake than 99m Tc-MDP...
August 22, 2018: Applied Radiation and Isotopes
Yasser S Soliman, Atef A Abdel-Fattah, Turki S Alkhuraiji
A radiation-sensitive polymer poly(hexa-2,4-diynylene adipate) (PHDA) was synthesized and incorporated into polyvinyl butyral films for radiation dose measurements in the 0.5 - 60 kGy range. PHDA undergoes crosslinking polymerization upon exposure to γ-rays, which changes its color from very pale yellow to deep orange-yellow. The color change is directly related to the absorbed dose. The absorption spectrum of the irradiated films features one absorption band around 500 nm with a shoulder around 465 nm...
August 21, 2018: Applied Radiation and Isotopes
Hyoe Takata, Mutsuo Inoue, Yuhei Shirotani, Natsumi Kudo
Radiocesium concentrations were measured in seawater and sediment samples collected in the swash zones in Ishikawa and Niigata prefectures, off the coast of Japan Sea opposite to the side where TEPCO Fukushima dai-ichi Nuclear Power Plant (FDNPP) is located in September 2016 and August 2017, five to six years after the accident. Cs-134 in the seawater samples was detected, suggesting the intrusion of FDNPP-derived radiocesium in both swash zones. FDNPP-derived radiocesium was appeared to be transported by the Tsushima Warm Current...
August 17, 2018: Applied Radiation and Isotopes
H B Shrivastava, N Rupa Rita, V Koteswara Rao, B Raghavender, Pravin Kumar Sharma
Various techniques are available for the estimation of uranium concentration in geological rock samples. In the uranium exploration program in India, the beta-gamma technique is widely used by the Atomic Minerals Directorate for Exploration and Research (Department of Atomic Energy) to estimate uranium concentration in natural rock or soil samples. Uranium concentration cannot be estimated accurately by the beta-gamma technique if the sample has high concentrations of thorium. Because the ratio of thorium to uranium concentration varies between 15 and 30 in monazite samples, uranium concentration in monazite samples cannot be estimated accurately by the conventional beta-gamma technique...
August 15, 2018: Applied Radiation and Isotopes
B K Soni, Rajnikant Makwana, S Mukherjee, Siddharth Parashari, S V Suryanarayana, B K Nayak, H Naik, M Mehta
The neutron capture cross-sections have been measured for the 159 Tb(n, γ)160 Tb reaction at the spectrum average peak neutron energies of 5.08 ± 0.165, 12.47 ± 0.825, and 16.63 ± 0.95 MeV respectively. The experiment has been carried out using the standard neutron activation technique and off-line γ-ray spectrometry. The present measurement has been done for the energies where very few measured results are available in the data library. The results have been compared with ENDF/B-VII.1 and JENDL-4...
August 15, 2018: Applied Radiation and Isotopes
Malihe Rostampour, Mahdi Sadeghi, Mohammadreza Aboudzadeh, Kamran Yousefi, Saeid Hamidi
The flow rate of coolant and the particle beam current are important when high beam current irradiations are intended for production of radionuclides. The beam current on nat Cu target to produce 63 Zn via the nat Cu(p,n)63 Zn reaction was investigated and the beam current was obtained more than 350 μA that is the maximum allowed beam current used for producing medical radioisotopes in Nuclear Science and Technology Research Institute of Iran. In addition, the temperature distribution on the target under the different cooling water flow rates has been simulated based on finite element analysis program...
August 15, 2018: Applied Radiation and Isotopes
Olga Fedorova, Viktoria Nikolaeva, Raisa Krasikova
[18 F]fluoroestradiol ([18 F]FES) is well-established PET radiotracer for diagnosing and monitoring treatment of estrogen-positive breast cancer. The radiotracer is produced via one-pot two steps synthesis using cyclic sulfate precursor and is usually purified by semi-preparative HPLC. Here we suggested simple SPE purification procedure using OASIS WAX 3cc and Sep-Pak QMA light cartridges that afforded [18 F]FES in typically 15% RCY (corrected for decay) within 45 min formulated in 5% EtOH/saline. All purity parameters were well within specifications recommended in the Investigator's Brochure for [18 F]Fluoroestradiol...
August 10, 2018: Applied Radiation and Isotopes
Tâmara P Teixeira, César M Salgado, Roos Sophia de F Dam, William L Salgado
Scale can be defined as chemical compounds that are inorganic, initially insoluble, and precipitate accumulating on the internal walls of pipes, surface equipment, and/or parts of components involved in the production and transport of oil. These compounds, when precipitating, cause problems in the oil industry and consequently result in losses in the optimization of the extraction process. Despite the importance and impact of the precipitation of these compounds in the technological and economic scope, there remains difficulty in determining the methods that enable the identification and quantification of the scale at an initial stage...
August 10, 2018: Applied Radiation and Isotopes
Muhammad Nabih, Ibrahim M Al-Alfy
The total shale volume is a physical parameter that plays a vital role in the evaluation of oil-bearing reservoirs. This study presents a new approach of shale volume calculation using the gamma ray spectrum of only thorium and potassium, avoiding the effect of uranium on gamma ray log (U-free). The calculations of shale volume based on U-free gamma ray log decreased to about 76%, 78%, and 79%, respectively, compared to the calculations based on the total gamma ray in clastic reservoirs in the abovementioned three regions...
August 9, 2018: Applied Radiation and Isotopes
S V Nikiforov, I G Avdyushin, D V Ananchenko, A N Kiryakov, A F Nikiforov
New Al2 O3 -BeO ceramics were synthesized from alumina nanopowder in BeO crucibles by high-temperature treatment in reducing conditions. It was found that the TL curve of these ceramics is characterized by a dosimetric peak at 520-530 K for a heating rate of 2 K/s. The integrated TL of the peak is not influenced by the heating rate of the samples, unlike that in anion-defective alumina and beryllia crystals. The presence of an energy distribution of the traps which cause dosimetric TL peak is verified by Tm-Tstop and initial rise methods...
August 7, 2018: Applied Radiation and Isotopes
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