Radiation Application Research School

Tehrān, Iran

Radiation Application Research School

Tehrān, Iran
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Medhat M.E.,Nuclear Research Center - Negev | Medhat M.E.,CAS Institute of High Energy Physics | Shirmardi S.P.,Radiation Application Research School | Singh V.P.,Karnatak University
Pramana - Journal of Physics | Year: 2017

Monte Carlo N-particle (MCNP) code has been used to simulate the transport of gamma photon rays of different energies (22, 31, 59.5 and 81 keV) to estimate the iron content in solutions. In this study, MCNP simulation results are compared with experiment and XCOM theoretical data. The simulation shows that the obtained results are in good agreement with experimental data, and better than the theoretical XCOM values. The study indicates that MCNP simulation is an excellent tool to estimate the iron concentration in the blood samples. The MCNP code can also be utilized to estimate other trace elements in the blood samples.


Adeli R.,Central Iran Research Complex Yazd | Shirmardi S.P.,Radiation Application Research School | Mazinani S.,Nanotechnology Research Institute | Ahmadi S.J.,Nuclear Fuel Cycle Research School
Kerntechnik | Year: 2017

In recent years many investigations have been done for choosing applicable light neutron shielding in space environmental applications. In this study, we have considered the neutron radiation- protective characteristics of neat epoxy resin, a thermoplastic polymer material and have compared it with various candidate materials in neutron radiation protection such as Al 6061 alloy and Polyethylene. The aim of this investigation is the effect of type of moderator for fast neutron, notwithstanding neutron absorbers fillers. The nuclear interactions and the effective dose at shields have been studied with the Monte Carlo N-Particle transport code (MCNP), using variance reductions to reduce the relative error. Among the candidates, polymer matrix showed a better performance in attenuating fast neutrons and caused a lower neutron and secondary photon effective dose.


Malekie S.,Radiation Application Research School | Ziaie F.,Radiation Application Research School | Naeini M.A.,Radiation Application Research School
Kerntechnik | Year: 2016

In this research work, the electrical behavior of polycarbonatecarbon nanotube composite, over the radiation absorbed dose under a fixed DC voltage was investigated via finite element method. The predicted electrical percolation threshold value in the composite was validated by experimental results published by other scientists. The absorbed dose value was considered as multiplying of heat capacity and temperature rise of the composite, regarding the calorimetric approach. Results show that this kind of composite can be applied for monitoring and radiation protection utilizations. © Carl Hanser Verlag, Munchen.


Shafaei M.,Radiation Application Research School | Ziaie F.,Radiation Application Research School | Hajiloo N.,Radiation Application Research School
Kerntechnik | Year: 2016

The goal of this study is to compare the thermoluminescence properties of nano and micro structure hydroxyapatite. Nano structure hydroxyapatite was synthesized via hydrolysis method, while the micro structure one was from Merck Company. X-ray diffraction and fourier transform infrared spectroscopy were used to determine the crystal structure and chemical composition of the hydroxyapatite samples. Particles sizes of each sample were estimated using Scherer equation and transmission electron microscopy system. Thermoluminescence properties of the samples were investigated under gamma irradiation. The glow curves of micro and nano structure samples show a peak at 150 8C and 200 8C, respectively. Thermoluminescence responses of both the samples were linear in the range of 25 - 1 000 Gy where, nano structure sample show a greater slope and stronger linearity in comparison to the micro sample. The results show that the thermoluminescence response of micro sample faded rapidly in comparison to the nano sample due to the existence of the peak at higher temperature. © Carl Hanser Verlag, Munchen.


Hosseinzadeh A.,Urmia University | Shayesteh N.,Islamic Azad University at Mahābād | Zolfagharieh H.,Medical and Industrial Research School | Babaei M.,Medical and Industrial Research School | And 3 more authors.
Journal of Plant Protection Research | Year: 2010

The effect of gamma irradiation on different developmental stages of Oryzaephilus surinamensis L., was investigated. Results showed that a required dose to prevent larval emergence from irradiated 1-2-days-old eggs was 60 Gray (Gy), and 350 Gy was required to prevent adult emergence from 15-days-old larvae. Also the required dose of radiation to prevent adult emergence from irradiated 5-days-old pupa was 700 Gy. The dose of 200 Gy caused 100% mortality of irradiated adults 28 days after treatment. In addition, the effect of gamma rays was studied on the developmental stage period of each irradiated stage till adult emergence. The results revealed that there was a dose-dependent increase of the developmental periods. The growth index of adults was significantly decreased with increasing dose of radiation administered to eggs, larvae and pupae. It is recommended that doses between 600 and 700 Gy should be used to control population growth of O. surinamensis when targeting pupae and adults present in stored products.


Abbas H.,Urmia University | Nouraddin S.,Islamic Azad University at Mahābād | Reza Z.H.,Medical and Industrial Research School | Iraj B.,Urmia University | And 4 more authors.
African Journal of Biotechnology | Year: 2011

Indian meal moth Plodia interpunctella Hübner is one of the most important stored products pests in the world. In this research, the effect of gamma irradiation was studied on different developmental stages of this pest and the doses required to prevent each of these developmental stages was investigated. From the results, required dose to prevent larval emergence from irradiated 1 to 24 h eggs was 400 Gray (Gy), and 400 Gy was required to prevent pupae from 15 days old larvae. Also, the dose of radiation required to prevent adult emergence from irradiated 5 days old pupa was 650 Gy. According to the results, dose of 650 Gy is adequate to control all immature stages of this pest. In addition, the effect of gamma ray was studied on developmental stage period of each irradiated existence stage till adult eclosion. The results revealed that there was a dose-dependent increase in the developmental periods, and the growth index of the adults was significantly decreased with increasing dose of radiation administered to the eggs, larvae and pupae too. It is concluded that irradiation can be used as a safe method to control stored pests. © 2011 Academic Journals.


Hooshangi Z.,Shahid Beheshti University | Feghhi S.A.H.,Shahid Beheshti University | Sheikh N.,Radiation Application Research School
Radiation Physics and Chemistry | Year: 2015

Engineering plastics like Poly (butylene terephthalate) due to their desirable properties have various industrial applications. Neat PBT is highly combustible, so it is necessary to improve significantly its fire retardancy to meet the fire safety requirements. The combustion performance of PBT can be improved by addition of appropriate flame retardant additives. In this study we have investigated the effect of halogen free flame retardants, i.e. melamine and aluminum phosphate, and instantaneously electron beam radiation-induced crosslinking in the presence of Triallyl cyanurate on various properties of PBT.The results of gel content showed that a dose range of 200-400. kGy leads to high cross linked structure in this polymer. Also mechanical experiments showed that its structure became rigid and fragile due to irradiation. Radiation crosslinking of this polymer made its dielectric loss coefficient ten times lower than non-irradiated polymer, but had no effect on its dielectric constant. Moreover the addition of the fire retardant additives as impurity decreased the dielectric loss coefficient. TGA analysis in nitrogen exhibited that irradiation increases char formation and use of the fire retardant additives leads to reduction of onset temperature and formation of higher char quantity than pure PBT. According to the results of UL-94, irradiated samples burned with lower speed and less dripping in vertical and horizontal positions than pure polymer. Finally irradiation of the polymers containing fire retardant additives with a dose of 400. kGy led to self-extinguishing and non-dripping and reach to V-0 level in the UL-94 V. © 2014 Elsevier Ltd.


Faripour H.,Laser and Optic Research School | Peyvandi R.G.,Radiation Application Research School | Islami rad S.Z.,Radiation Application Research School
Crystallography Reports | Year: 2014

Improvement of crystal performance is important for the nuclear instrumentation, medical imaging and radiation measurement as industrial application. For achieving this aim, we developed to establish crystal growth process and design and fabricate crystal growth equipment. Finally, the single crystal scintillator of NaI (Tl) was grown successfully by the conventional Czochraski method and Thallium quantity was measured through grown crystal. The results showed Thallium losses by evaporation during crystal growth. Thus, the first part of grown NaI(Tl) (2.5 cm) has high light yield and is suitable for counter. The characteristics of the grown NaI(Tl) were evaluated on the excitation, emission responses. Finally, grown crystal was used as scintillators in nuclear radiation detection, industrial applications and etc. © 2014, Pleiades Publishing, Inc.

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