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Mahdi Sadeghi Zeanab Ansari Tayeb Kakavand 《Journal of Radioanalytical and Nuclear Chemistry》2012,293(1):7-12
The radionuclide vanadium-48 (T 1/2?=?16?d, ?? +=?49.5?%) could be employed to positron emission tomography. In this Study, 48V excitation function for the nat/49/48Ti(p,x)48V and the 48Ti(d,2n)48V nuclear reactions were calculated by ALICE/ASH code. Then recommended thickness of the targets according to the SRIM-2010 code was calculated; consequently, the theoretical integral yields were computed for all reactions by the computer software. As a result, the 48Ti(p,n)48V reaction was determined as the best reaction. Ti target was prepared by sedimentation method to produce 48V throughout accelerator proton bombardment. 相似文献
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Solvent‐free organic reactions were studied over periodic mesoporous silica (SBA‐15) containing a Cu(II) organometallic complex. This heterogeneous catalyst was achieved by coordination of Cu(II) ions with the diaminosarcophagine ligand and then its grafting onto the surface of SBA‐15. This catalyst displayed ordered mesoporous channels, which implies an extremely high dispersion of the Cu(II) complex and the convenient diffusion of reactant molecules into the pore channels. Therefore, this catalyst can offer high activity and also facile separation or recycling when compared with its homogeneous counterparts. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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T. Kakavand M. Sadeghi L. Mokhtari A. Majdabadi 《Journal of Radioanalytical and Nuclear Chemistry》2010,283(1):197-201
The electroplating of zinc is carried out in an alkaline cyanide bath. Operating parameters such as pH, temperature, and current
density and amount of the electrolyte components are optimized. The optimum conditions of the electrodeposition of zinc were
as follows: 2.7 g L−1 ZnO, 7.1 g L−1 KCN, 11.1 g L−1 KOH, pH = 13–14, DC current density of ca 8.55 mA cm−2 at 40–50 °C temperature with 89% current efficiency. SEM photomicrographs revealed fine-grained structure of the deposit
from the bath. 相似文献
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Mohammad Mirzaii Teyeb Kakavand Motahare Talebi Saeed Rajabifar 《Journal of Radioanalytical and Nuclear Chemistry》2012,292(1):261-267
Natural iron electrodeposition on copper substrate was studied with the aim of production of cobalt-55 radionuclide. 55Co seems well suited for PET imaging due to its high abundance of positron decay (I
β+ = 76%), its relatively long half-life (T
1/2 = 17.5 h) and its mean positron energy (E
avg = 570 keV). The electrodeposition experiments were carried out by chloride bath. Operating parameters such as pH, temperature,
current density and amount of the electrolyte components are also optimized. The optimum conditions of the iron electrodeposition
were follows: 8 g/L FeCl2, 2 g/L CaCl2, pH = 1, DC current density of 21.3 A/dm2 with a bath temperature of 75 °C temperature and 20% current efficiency. SEM photomicrographs demonstrated fine-grained structure
of the deposit obtained from the optimum bath. The electroplated iron-target was irradiated with 29.5 MeV protons at current
of 100 μA for 1 h and yields of about 31.25 MBq/μAh were experimentally obtained. 相似文献
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Gallium-68 (T
1/2 = 68 min, I
β+ = 89%) is an important positron-emitting radionuclide for positron emission tomography and used in nuclear medicine for diagnosing
tumours. This study gives a suitable reaction to produce 68Ga. Gallium-68 excitation function via 68Zn(p, n)68Ga, 68Zn(d, 2n)68Ga, 70Zn(p, 3n)68Ga and 65Cu(α, n)68Ga reactions were calculated by ALICE-91 and TALYS-1.0 codes. The calculated excitation function of 68Zn(p, n)68Ga reaction was compared with the reported measurement and evaluations. Requisite thickness of the targets was obtained by
SRIM code for each reaction. The 68Ga production yield was evaluated using excitation function and stopping power.
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Semiconductor detectors based on a silicon pin diode are frequently used in the detection of different nuclear radiations. For the detection and dosimetry of fast neutrons, these silicon detectors are coupled with a fast neutron converter. Incident neutrons interact with the converter and produce charged particles that can deposit their energy in the detectors and produce a signal. In this study, three methods are introduced for fast neutron dosimetry by using the silicon detectors, which are: recoil proton spectroscopy, similarity of detector response function with conversion function, and a discriminator layer. Monte Carlo simulation is used to calculate the response of dosimetry systems based on these methods. In the different doses of an 241Am-Be neutron source, dosimetry responses are evaluated. The error values of measured data for dosimetry by these methods are in the range of 15-25%. We find fairly good agreement in the 241Am-Be neutron sources. 相似文献
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