Mehrdad Shamsinasab; Mansour Asgari; Mahdi Eshghi
Abstract
Nuclear-pumped lasers (NPL) are lasers that excite the active laser environment caused by nuclear reaction. Such lasers need ionizing radiation shielding for mixed neutron and gamma fields. In this work, a shielding system for NPL was designed which using 10B(n,α)7Li. In this simulation, we have ...
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Nuclear-pumped lasers (NPL) are lasers that excite the active laser environment caused by nuclear reaction. Such lasers need ionizing radiation shielding for mixed neutron and gamma fields. In this work, a shielding system for NPL was designed which using 10B(n,α)7Li. In this simulation, we have used MCNPX 2.6.0 Monte Carlo code and the thermal neutron flux as 1×1016 n.cm-2.s-1 for excitation reaction. Such a large neutron flux can be obtained from a reactor source or a heavy ion accelerator. For this work, 10B fuel is covered on the surface of a rectangular cube aluminum shell by using the Monte Carlo method. In the design of the shielding, combinations with different materials have been used with various arrangements in three layers. According to the simulation, the arrangement of Fe2-B-BPE-Pb is a suitable protection compound for such lasers.
Berat Can Karatas; Ho Namgoong; Hoseung Song; Donghyup Ha; Jong-Seo Chai; Mitra Ghergherehchi
Abstract
A four-sector 14 MeV azimuthally varying field H-type cyclotron magnet has been designed for positron emission tomography (PET) at Sungkyunkwan University. Compactness, feasibility, and high performance are among the main factors that were considered in the design, which is ultimately intended made for ...
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A four-sector 14 MeV azimuthally varying field H-type cyclotron magnet has been designed for positron emission tomography (PET) at Sungkyunkwan University. Compactness, feasibility, and high performance are among the main factors that were considered in the design, which is ultimately intended made for use in hospitals and research institutes. After optimizing the initial parameters using the shimming method, an isochronous magnetic field along the cyclotron radius through Opera-3d was investigated. The particle trajectories were also illustrated. The Cyclone equilibrium orbit code program was used to examine the radial and axial betatron oscillations in relation to the cyclotron operating points. In addition, the integrated phase shift was explained and compared to the Korea Institute of Radiological Medical Sciences 13 MeV cyclotron (KIRAMS-13). In conclusion, the final shape magnet satisfied the orbital stability requirements. The RF cavity, vacuum pump, and injection system could be employed efficiently, and a reliable agreement was reached between KIRAMS-13 and our design characterization.
Sedigheh Kashian; Hamideh Daneshvar; Peiman Rezaeian; Mohammad Rafiean
Abstract
Irradiation of agricultural products is used to optimize properties and pest control and also increase the storage time of products. The desired irradiation result is obtained when the required dose is given to the sample. Dosimetry is a method for separating and classifying ...
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Irradiation of agricultural products is used to optimize properties and pest control and also increase the storage time of products. The desired irradiation result is obtained when the required dose is given to the sample. Dosimetry is a method for separating and classifying materials and equipment that is provided to the user to confirm the acceptance of irradiation and control the performance. In this work, Chromium Nitrate solutions with concentrations of 0.16, 0.24, and 0.32 mM have been prepared and irradiated with gamma rays between 100 to 1000 Gy. The purpose of this study is to investigate the dosimetry of these samples in the range of irradiation of agricultural products. Results show that the higher concentration sample is linear in about 100 to 1000 Gy dosimetry range and the optimal concentration must be found to achieve a stable sample in about 3 weeks periods. Also, samples that are in a darker environment are more stable than samples that are in a lighter environment.
Mahmoud Abdoulahpour; Mohammad Reza Rezaie; Saeed Mohammadi
Abstract
Hot springs are known as one of the hydrotherapy centers in the world and have been welcomed due to their healing properties. Due to the presence of radon and radioactive elements in hot spring sediments, water and soil, these components are radioactive. So far, radiation hazards and the annual effective ...
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Hot springs are known as one of the hydrotherapy centers in the world and have been welcomed due to their healing properties. Due to the presence of radon and radioactive elements in hot spring sediments, water and soil, these components are radioactive. So far, radiation hazards and the annual effective dose of hot spring components in the body organs have not been investigated in Iran. The purpose of this study was to calculate the amount of U-238, Cs-137, Th-232, and K-40 elements in soil, water, and sediments of Jooshan hot springs in the Kerman region. The presence of these elements causes radiation hazards and an effective annual dose in people who use these hot springs. In addition to the healing properties of hot springs, the high amount of radiation hazard and effective annual dose may cause cancer risk. Experimental results with CsI(Tl) detector showed that the total activities of these elements in soil, water, and sediments of Jooshan hot spring were 95.26±9.76, 52.86±7.27, and 51.61±7.18 Bq.kg-1 respectively. The Jooshan hot spring's radiation hazards were calculated using activity measurement of the radioactive elements in soil, water, and sediments which was less than the permission level. The result of the Monte Carlo simulation with the MCNPX code showed that the effective annual dose of sediment, water, and radon in Jooshan hot spring are 5.43E-06, 3.00×10-3 and 1.16×10-1 mSv.year-1 respectively, which is less than effective annual dose (5 mSv.year-1). The maximum time for treatment by hot spring water is considered equal to one year.
Ramin Mehrabifard
Abstract
Dielectric barrier discharge (DBD) plasma is used for various applications. DBD is also one of the most efficient and low-cost methods for active fluid flow control. In this study, a detailed physical model of DBD in atmospheric pressure at 1 kV DC voltage is developed with COMSOL Multiphysics software. ...
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Dielectric barrier discharge (DBD) plasma is used for various applications. DBD is also one of the most efficient and low-cost methods for active fluid flow control. In this study, a detailed physical model of DBD in atmospheric pressure at 1 kV DC voltage is developed with COMSOL Multiphysics software. Argon gas is also used as a background gas and electrodes are assumed to be copper. Plasma parameters such as electron and ion density, electric field, potential, and temperature for different gap distances of electrodes (1.0 mm, 0.9 mm, 0.8 mm) and different dielectric types (Quartz, Silica Glass, Mica). The results of the simulation show that the longitudinal distance of the grounded electrodes to the power electrodes has a direct influence on parameters such as electron temperature, and electron and ion density which are the main factors of fluid flow control. These parameters have the maximum value when Mica is used as a dielectric and the lowest value when Silica Glass is utilized.
Zohreh Gholamzadeh; Reza Ebrahimzadeh; Mohammad Hossein Choopan Dastjerdi; Javad Mokhtari
Abstract
New nitrile butadiene rubber (NBR) materials are being considered to use for neutron shielding especially for the positions which needs a flexible neutron shield. Such light, low-cost, and suitable material could be used for sealing of the gaps or even for shielding of low radiation environments. In ...
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New nitrile butadiene rubber (NBR) materials are being considered to use for neutron shielding especially for the positions which needs a flexible neutron shield. Such light, low-cost, and suitable material could be used for sealing of the gaps or even for shielding of low radiation environments. In the present work, experimental investigation of NBR shielding performance of neutrons and gamma rays was proposed using the beam line of the Isfahan Miniature Neutron Source Reactor . MCNPX code was used to simulate the 30 kW research reactor beam line. Six NBR sheet with 2 cm thickness were used at the outlet of the beam line respectively to measure its neutron shielding as well as gamma shielding power on thickness. The experiment situations were modeled using the computational code. The obtained results showed the flexible and cheap material could be used as a good neutron shield while it acts as a very weak shield for gamma rays too. Also there is good conformity between simulation and experimental data with maximum 37% relative discrepancy.
Ehsan Boustani; Mostafa Hassanzadeh; Rohollah Ahangari
Abstract
The occurrence of core uncovering following a loss of coolant accident is conceivable and should be taken into account for its significant possible consequences. Source terms are calculated using ORIGEN 2.1 code, and the gamma dose of the uncovered core is calculated for three different normal and anticipated ...
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The occurrence of core uncovering following a loss of coolant accident is conceivable and should be taken into account for its significant possible consequences. Source terms are calculated using ORIGEN 2.1 code, and the gamma dose of the uncovered core is calculated for three different normal and anticipated accidents scenarios. Under containment gamma dose rates have been calculated analytically as well as using MCNPX 2.6.0 code. The uncovered core of the Tehran research reactor is supposed to operate in nominated power of 5 MW for 30 days. The results illustrated that the under-containment dose rate of gamma in some locations would be about 200 Svh-1, far from the annual occupational exposure limit of 50 mSv. For preventing this occurrence, it would be possible to use an emergency make-up tank as an engineered safety feature, with functions of the avoidance of damaging fuel after the loss of coolant accident as well as controlling exposure from the core.
Reza Pourimani; Saeed Ghahani; Parisa Nobakht; Iman Mirzae Moghadam
Abstract
Today, with the development of nuclear technology and radiation therapy equipment, radiation protection is important. This study aimed to design heavy concrete with high compressive strength and effective protection against neutron and gamma rays. In this study, 11 types of concrete with different mixing ...
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Today, with the development of nuclear technology and radiation therapy equipment, radiation protection is important. This study aimed to design heavy concrete with high compressive strength and effective protection against neutron and gamma rays. In this study, 11 types of concrete with different mixing designs including 88 samples were made. In these samples, iron ore aggregates galena, limonite, hematite, polypropylene fibers, nanoparticles, micro-particles of silicon, and B4C powder have been used. Concrete quality coefficient, compressive strength, gamma, and neutron attenuation coefficients were measured for all samples. Also, the neutron attenuation coefficient for all samples was calculated using the Monte Carlo simulation (MCNPX) code and compared with the experimental values. The density, neutron attenuation coefficient, and compressive strength of concrete samples varied from 2.37 to 3.17 g.cm-3, from 0.0162 to 0.0306 cm2.g-1, and from 48.0 to 81.3 MPa respectively. The linear gamma attenuation coefficient and gamma-ray tenth value layer (TVL) were obtained from 0.148 to 0.398 cm-1 and 15.74 to 5.85 cm respectively. These results showed that the highest neutron and gamma attenuation coefficients were obtained for concrete containing 70% galena iron ore and 20% boron carbide and the highest compressive strength belonged to sample G15 containing 15% galena iron ore and 1.8% boron carbide. G70 was the best concrete regarding the quality factor, defined as the product of multiplying the compressive strength and linear attenuation coefficients of neutron and gamma.
Elham Edalatkhah; Shahab Sheibani
Abstract
By expanding the applications of GEM detectors, a newer pattern of such detectors was introduced in 2004, named THGEM detectors. In this work, a sample of an X-ray detector was designed and constructed using 2cm×2cm THGEMs domestically produced with a thickness of 250 μm, a hole diameter of ...
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By expanding the applications of GEM detectors, a newer pattern of such detectors was introduced in 2004, named THGEM detectors. In this work, a sample of an X-ray detector was designed and constructed using 2cm×2cm THGEMs domestically produced with a thickness of 250 μm, a hole diameter of 300 μm and a pitch of 500 μm, for the first time. The triple THGEM detector working in Ar/CO2 gas mixture was characterized. Influence of gas pressure and gas mixture on gain of the detector was investigated. Results show the detector operated in a stable mode with no discharges. The gain of the detector increased with high voltage across the THGEM electrodes exponentially. This verified the performance of a detector as a proportional counter. Also, the detector’s gain is maximum at Ar/CO2 (80/20) gas mixture and voltage of 700 V applied to each multiplier. The detector is promising for localization applications such as particle physics experiments.
Sajad Hajikhani; Ramin Mehrabifard; Hamed Soltani Ahmadi
Abstract
Plasma technology has undeniably revolutionized industrial processes in recent decades. Atmospheric pressure plasma (APP) has emerged as a prominent and widely applicable tool in various scientific disciplines. Notably, plasma-assisted flow control has become a subject of intense interest, particularly ...
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Plasma technology has undeniably revolutionized industrial processes in recent decades. Atmospheric pressure plasma (APP) has emerged as a prominent and widely applicable tool in various scientific disciplines. Notably, plasma-assisted flow control has become a subject of intense interest, particularly applying surface dielectric barrier discharge (SDBD) plasma actuators for aerodynamic flow control. In this study, a two-dimensional model of the SDBD plasma actuator is developed using the COMSOL Multiphysics program, incorporating air gas discharge reactions with N2/O2/Ar gases in specific ratios (0.78, 0.21, 0.01). The investigation focuses on the impact of dielectric materials (mica, silica glass, quartz, and polytetrafluoroethylene (PTFE)) on plasma characteristics and body force within the plasma actuator under constant input parameters. Moreover, the study explores how variable pressure (760, 660, and 560 torr) in different applications influences plasma properties, ultimately affecting the magnitude of the body force in the plasma actuator. These findings contribute to optimizing plasma technology for flow control applications and enhance industrial efficiency and performance.
Hamed Khodadadi; Kamyar Sabetghadam
Abstract
Probabilistic uncertainty and sensitivity analysis is frequently recommended for safety and reliability assessment of computer simulations. For this purpose, SUAP has been developed, and its latest version is capable of working on analysis results obtained using five well-known nuclear codes (i.e. FRAPCON, ...
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Probabilistic uncertainty and sensitivity analysis is frequently recommended for safety and reliability assessment of computer simulations. For this purpose, SUAP has been developed, and its latest version is capable of working on analysis results obtained using five well-known nuclear codes (i.e. FRAPCON, FRAPTRAN, FEMAXI, MCNP, and COBRA). SUAP provides support to properly quantify input uncertainties as to probability distributions and appropriate dependency functions. Using the Monte-Carlo sampling method, random combinations of different uncertain input parameters are generated and used to make input files for the corresponding code applied for the modeling. To quantify uncertainties, SUAP determines the variation range for each specific output parameter at any chosen time and/or location. Moreover, sensitivity analysis is accomplished based on the Spearman correlation. In this study, in order to evaluate SUAP applicability, UQ&SA for fuel performance modeling of VVER-1000 fuel rods using FRAPCON code has been accomplished. Acquired results exhibit the possible range of uncertainties in fuel centerline temperature, as well as the importance of different uncertain input parameters on that.
Roohalah Mirzaeian; Seyede Nasrin HoseiniMotlagh; Mahboobeh Shaghaghian
Abstract
In recent years, various designs for controlled thermonuclear fusion based on the p11B reaction have been reviewed and optimized. In this article, to innovate in achieving a better power and energy gain of neutron-free p11B fusion reaction, the improvement of the cross-section and also the kinetic effects. ...
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In recent years, various designs for controlled thermonuclear fusion based on the p11B reaction have been reviewed and optimized. In this article, to innovate in achieving a better power and energy gain of neutron-free p11B fusion reaction, the improvement of the cross-section and also the kinetic effects. Then, the effects of bremsstrahlung radiation and ion and electron energy exchange rate have been evaluated by introducing relativistic effects and its role on improving fusion energy gain. As a result, the temperature of the electron is kept lower than that of the ion, which improves fuel performance. Finally, it leads to an increase in the number of protons at higher energies compared to the pure Maxwellian distribution and it causes a significant increase in reactivity compared to previous research. Also, the number of alpha particles obtained through calculations coincides with the latest research and leads to an enhancement of approximately 13%. This means that by improving the fusion cross-section of p11B, our calculations show that considering the avalanche effects, the range of achievable energy gain in the temperature range of 300 to 500 keV and the stable characteristic time of 0.64 ps reaches 89 to 111. While in the same temperature range and with the stable characteristic time of 0.74 ps, regardless of the improved cross-section, the energy gain range is 75 to 98.
Saba Khatami; Mohammad Mahdavi; Sohail Khoshbinfar
Abstract
In this research, the effect of deuterium beam energy distribution function resulting from TNSA and RPA mechanisms on the fast ignition of D/He-3 fuel pellet has been investigated. The fuel is irradiated with a deuterium beam through a conical guide. The energy distribution function will be different ...
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In this research, the effect of deuterium beam energy distribution function resulting from TNSA and RPA mechanisms on the fast ignition of D/He-3 fuel pellet has been investigated. The fuel is irradiated with a deuterium beam through a conical guide. The energy distribution function will be different in different mechanisms. Penetration depth and stopping power of ignitor beam with mono- energy, Maxwellian and Gaussian distribution of energy are calculated. Calculations show that the Maxwellian beam from TNSA mechanism, penetrates up to about 100 μm in the fuel and the height of deposition peak is still in plasma corona. The height of the peak has also increased about 25 times compared to the case where the Gaussian beam is considered. Also, the obtained results are shown that the energy deposit of the deuterium beam resulting the RPA mechanism will be completely localized and will be more concentrated in the dense fuel core.
Farshid Pourranjbar; Elham Edalatkhah; Seyed Mohammad Mahdi Abtahi
Abstract
Fricke gel dosimeters obtained by modifications on standard Fricke dosimeter presents some advantages like easy preparation, tissue equivalence, good reproducibility and dose mapping. In this work, dose response characteristics of Gelatin Fricke gel dosimeters ...
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Fricke gel dosimeters obtained by modifications on standard Fricke dosimeter presents some advantages like easy preparation, tissue equivalence, good reproducibility and dose mapping. In this work, dose response characteristics of Gelatin Fricke gel dosimeters was investigated and compared with Fricke agarose gel dosimeters in terms of sesitivity. After prepration of three different formulation of Gelatin Fricke gel dosimeters and gamma irradiation of the samples, a spectrophotometer was applied to measure the optical absorbance of the samples. Results indicate a linear dose range response of 10 to 30 Gy, as well as increased gelatin concentrations cause the sensitivity of the dosimeter to detereorate with a 80% reduction of dose response for a change in gelatin concentration from 3 to 8 weight percent. Obtained coefficient variation verifies the good repeatability of the gel response. The gel dosimeter has no dose rate dependence. Comparison of the most sensitive Gelatin Fricke gel sample with the prepared Fricke agarose gel samples confirm that Fricke agarose dosimeter is more sensitive than Gelatin Fricke gel dosimeter.
Reza Pourimani; Monire Mohebian; Mobina Abdi
Abstract
Nuclear radiations are harmful to the human body. The main sources of nuclear radiation are the decay chains of U-238, U-235, and Th-232 and also some radionuclides as K-40, which are present in small amounts in the materials of the earth's crust, including plants, rocks, soil and water. Radioactive ...
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Nuclear radiations are harmful to the human body. The main sources of nuclear radiation are the decay chains of U-238, U-235, and Th-232 and also some radionuclides as K-40, which are present in small amounts in the materials of the earth's crust, including plants, rocks, soil and water. Radioactive substances are transferred to the human body in a variety of ways, including plant and animal products. Therefore, it is very important to determine the amount of radioactive substances in food products. In this research, seven samples of pistachios with different types were collected from Tehran markets in Iran. In this project, ultra-pure germanium spectroscopy system model GCD30195 was used. The specific activities of Ra-226, Th-232 and K-40 varied from <1.96 to 9.86, from 1.21 to 1.95, and from 317.22 to 382.80 Bq.kg-1. The artificial radionuclide of Cs-137 in all samples was lower than minimum detectable value (MDA). Calculations of the radiological impact showed that consumption of pistachios would endanger human health. The results of this study also showed that the amount of natural radionuclides in pistachio cores is higher than pistachio shells.
Hamed Kargaran
Abstract
The estimation of flux in radiation transport Monte Carlo problems needs to calculate the volumes and surface areas of the geometric regions. The particle flux is often estimated as the track length per unit volume or the number of particles crossing a surface per unit area in Monte Carlo transport problems. ...
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The estimation of flux in radiation transport Monte Carlo problems needs to calculate the volumes and surface areas of the geometric regions. The particle flux is often estimated as the track length per unit volume or the number of particles crossing a surface per unit area in Monte Carlo transport problems. Various representations such as constructive solid geometry (CSG), boundary representation (B-Rep), and combinatorial geometry (CG) are proposed in the literature for geometry modeling and calculation of surface area and volume. MCNP series and OpenMC as Monte Carlo particle transport codes utilize CG modeling and are not able to calculate surface area as well as volume for non-rotationally symmetric or non-polyhedral cells. In this work, a comprehensive approach based on the Cauchy-Crofton formula using the Monte Carlo method has been implemented to the radiation transport codes as an extra module for computing surface area and volume of complex geometries. We used a random sampling procedure to create the required probe lines and points in the computational approach. The results show that this method can accurately compute surface areas and volumes of complex geometries with a relative error of less than 0.1% and a short computation time of a few seconds, which is not achievable with the cuurent MCNP and OpenMC modules.
Morteza Akbari; Farrokh Khoshahval
Abstract
In this research, the governing dynamic equations of the Bushehr NPP core are studied and modeled using Matlab (Simulink) software. The point kinetic equation with the temperature feedbacks and the fuel-coolant energy balance equations in the time domain were used for this purpose. The model is validated ...
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In this research, the governing dynamic equations of the Bushehr NPP core are studied and modeled using Matlab (Simulink) software. The point kinetic equation with the temperature feedbacks and the fuel-coolant energy balance equations in the time domain were used for this purpose. The model is validated against the rod drop accident data available in BNPP-1 FSAR, and they agreed. Then, this time-domain model is used to find the maximum movement speed of the control rods. For this goal, linear and non-linear rod movement equations have been modeled. In this regard, the maximum withdrawal speed of the working bank (H10) with a worth of 1.1 dollars has been investigated. Using the linear CR model, a speed limit of 9 cm.s-1 has been obtained to prevent the initiation of a reactor trip. The maximum speed using the non-linear model of the CR was found out to be dependent on its initial position. Thus, in three positions of the H10 bank: 100%, 80%, and 50% of the length inside the reactor, the maximum withdrawal speed values were valuated 11.5, 7.7, and 4.4 cm.s-1 respectively. According to the results, among the reactor parameters including power, period, and fuel temperature, which are monitored by the reactor protection system to initiate the reactor trip, the reactor power is the limiting factor for specifying the maximum withdrawal speed. This study is performed using time domain analysis, and the obtained results are consistent with the results reported in the previous research using Laplace transform approach.
Leyli Mogheiseh; Ali Asghar Mowlavi; Sayyed Bijan Jia; Reza Shamsabadi
Abstract
Proton therapy of liver tumors can be challenging due to the absorbed dose of produced secondary particles in non-target organs. This study aims to evaluate the absorbed dose of secondary particles during the proton therapy of liver cancer through the MCNPX Monte Carlo (MC) code by a simplified MIRD-UF ...
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Proton therapy of liver tumors can be challenging due to the absorbed dose of produced secondary particles in non-target organs. This study aims to evaluate the absorbed dose of secondary particles during the proton therapy of liver cancer through the MCNPX Monte Carlo (MC) code by a simplified MIRD-UF standard phantom. At first, a simplified MC model of MIRD-UF standard phantom was simulated using MCNPX. After the proper proton energies calculation ranging from 90 to 120 MeV for 4×4×4 cm3 tumor irradiation, mesh tally type 3 and F6 tally were used to calculate the depth dose profiles as well as the absorbed dose of protons and secondary particles in non-involved organs. The obtained results illustrated that the fluence of internal secondary particles doses was considerably small in comparison with primary protons. Furthermore, most of neutrons and photons doses were absorbed around the liver tissue for all performed proton energies (i.e., 90 and 120 MeV) which non-target organs did not receive a significant high dose. Furthermore, the absorbed dose of secondary photons and neutrons had slight variations in considered normal tissues near the liver. The calculated results in this study indicated that during the proton therapy of liver cancer, the most contribution of the secondary particle doses was absorbed inside the liver tissue. Hence, it can be expected the probable side effects (secondary cancers) associated with the liver cancer proton therapy may be decreased however, the presence of secondary particles should not be ignored.
Nahid Hajiloo; Mostafa Mohammadi; Omid N. Ghodsi; Hamideh Daneshvar; Soheil Moghtader
Abstract
The International Atomic Energy Agency (IAEA), sends dosimeters annually to Secondary Standard Dosimetry Laboratories (SSDL) around the world, to calibrate their radiation field. Therefore, they mainly send thermo-luminescent dosimeters as transfer dosimeters to the SSDL laboratories, to be irradiated ...
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The International Atomic Energy Agency (IAEA), sends dosimeters annually to Secondary Standard Dosimetry Laboratories (SSDL) around the world, to calibrate their radiation field. Therefore, they mainly send thermo-luminescent dosimeters as transfer dosimeters to the SSDL laboratories, to be irradiated under the requested conditions and sent back to the IAEA laboratories for reading. In this way, by reading the dosimeters, the uncertainty of the dosimetry carried out by SSDL and, consequently, the calibration of its radiation fields is determined. In this research, with the aim of feasibility of comparative dosimetry program by SSDL laboratory for radiation therapy centers, this program was carried out for a number of centers. In this way, TLD-700 thermoluminescence dosimeters were irradiated in the same conditions in the SSDL laboratory and also in the selected centers to a certain amount. After reading and applying the correction coefficients and calibration factors, the obtained results were compared with the measurement results using ion chamber reference dosimeter. In this work the uncertainty of the dosimetry using TLD tablet was less than 1.12% in comparison to the reference ionization chamber dosimeter and was within the acceptable range of less than 3%.
Elham Edalatkhah; Mahsa Sedighi; Payvand Taherparvar
Abstract
Gamma radiation indicators are appropriate tools for monitoring visually whether or not the irradiation process has been carried out properly. Among chemical radiation indicators available worldwide, a few are suitable for monitoring low dose ranges (especially for blood irradiation, below 50 Gy). Addressing ...
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Gamma radiation indicators are appropriate tools for monitoring visually whether or not the irradiation process has been carried out properly. Among chemical radiation indicators available worldwide, a few are suitable for monitoring low dose ranges (especially for blood irradiation, below 50 Gy). Addressing this scope, PVA-Fricke gel was proposed in this work. Irradiation of the prepared PVA-Fricke gel samples was performed by Co-60 gamma cell unit up to a dose of 80 Gy. Color change of the samples was observed from orange to purple proportional to increasing absorbed dose. Prepared samples were divided into three groups, kept at different environmental conditions, to investigate stability of the gel against temperature and light. Results revealed that the irradiated samples kept at dark and refrigerator were stable for seven days. Optical absorbance measurement of the samples also estimated pre- and post-irradiation color stability. The gel can be easily used to identify processed and unprocessed products in blood irradiation. Although the gel is designed to be a qualitative indicator, it is also a good quantitative dosimeter for gamma rays.
Experimental and Theoretical Nuclear Physics
Zeinab Sadat Imani; Omidreza Kakuee; Yavar Taghipour Azar; Amir Abbas Sabouri Dodaran
Abstract
The production of light, energetic and low-flux ions as a secondary beam caused by nuclear reaction can be used in various branches of nuclear physics. Due to the limited availability of energy in small laboratories equipped with electrostatic accelerators, accessing energetic light particles is crucial. ...
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The production of light, energetic and low-flux ions as a secondary beam caused by nuclear reaction can be used in various branches of nuclear physics. Due to the limited availability of energy in small laboratories equipped with electrostatic accelerators, accessing energetic light particles is crucial. For this purpose, selected nuclear reactions were introduced. In this research, primary proton, deuterium and helium-3 beams with energy less than 2 MeV were used for samples with a thickness of 1019 atom.cm-2 and the yield of reactions was obtained. The laboratory setup was designed in such a way that in addition to the access to the nuclear reaction products with a suitable yield, favorable conditions were provided for the extraction and transfer of the reaction products as well as their interaction with the sample. In these exothermic nuclear reactions, the yield is in the order of 106 particles and secondary proton and alpha particles with energies of 4 to18.5 MeV have been obtained. Also, the selected reactions are in accordance with the radiation protection protocols of similar laboratories.
Nuclear Reactor science and Technology
Ehsan Boustani
Abstract
Due to the diverse uses of research reactors compared to power reactors, a variety of safety aspects must be considered in their design and operation. On the other hand, due to the high age of a large percentage of these reactors, the need to update them in order to respond to the growing needs of today's ...
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Due to the diverse uses of research reactors compared to power reactors, a variety of safety aspects must be considered in their design and operation. On the other hand, due to the high age of a large percentage of these reactors, the need to update them in order to respond to the growing needs of today's society is inevitable. One of the items that increase the features in terms of proliferation, economy, usability, security and nuclear to meet the requirements of today's society is core conversion. The advantages and necessities of using new fuel in research reactors include the possibility of forming a more compact core, reducing operating costs, reducing security challenges, protection, environmental effects, transportation and end-of-cycle processes. In this study, the roadmap for research reactors core conversion is drawn considering all aspects of this issue which would be very useful for research reactor plan of any country especially our country.
Measurement of Radiation and Radioactivity
Alireza Goosheh; Seyed Mehdi Abtahi; Ahmad Akhound; Seied Rabi Mahdavi
Abstract
The Persistent development of quick and accessible readout tools promises to remove one of the barriers to the adoption of gel dosimetry as an applicable method in treatment clinics. Research and development in the imaging of polymer gel dosimeters continues with a focus on imaging in three dimensions. ...
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The Persistent development of quick and accessible readout tools promises to remove one of the barriers to the adoption of gel dosimetry as an applicable method in treatment clinics. Research and development in the imaging of polymer gel dosimeters continues with a focus on imaging in three dimensions. Each technique comes with its own set of advantages and challenges. In gel dosimeter research, efforts have been made to identify and develop alternative imaging methods for polymer gel dosimeters. Gel dosimeters can obtain reliable and accurate three-dimensional dose distributions from the correlation of different polymerization stages caused by radiation. The irradiated samples are examined using magnetic resonance imaging, optical computed tomography, and X-ray computed tomography. This research describes the basic features of imaging devices and the readout of irradiated dose data. Costs, availability, portability, contrast and resolution, high-resolution image reconstruction algorithm, and image reconstruction time of radiation absorption dosimeters for imaging devices are investigated in this research. This review has been done to present the mentioned imaging features and review the research done in this field for the optimal use of different imaging methods.
