Shahryar Malekie; Seyed Musa Safdari; Sedigheh Kashian; Morteza Akbari
Abstract
Polycarbonate-bismuth oxide composite has been used as a beta-ray sensor in the previous works. Calculation of two main quantities namely stopping power and range of electrons in this material can be useful to evaluate the optimal thickness of the sensor. Thus, in this study, the range of electrons and ...
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Polycarbonate-bismuth oxide composite has been used as a beta-ray sensor in the previous works. Calculation of two main quantities namely stopping power and range of electrons in this material can be useful to evaluate the optimal thickness of the sensor. Thus, in this study, the range of electrons and stopping power of polycarbonate/bismuth oxide composite for several pure beta-emitters were estimated using the ESTAR program. Simulation findings indicated that the amount of concentration of the heavy metal oxide particles into the composite is an important factor to determine the range and stopping power of the electrons. Also, in the experimental phase, the response of the 50 wt% nanocomposite with thickness of 1 mm against the beta-rays of the P-32 source at the average energy of 695 keV in different activities was measured using an electrometer at a constant voltage of 800 V. Results showed that the response of the sample ranging from 4 to 6 mCi was linear with R2= 0.9757.
Vahidreza Babaei; Peiman Rezaeian; Sedigheh Kashian; Reza Pourimani; Azam Akhavan
Abstract
In this paper, the spectrophotometric properties of a colored Nickel-based solution complex (Nickel nitrate hexahydrate and Methyl Orange (MO)) were investigated as a stable chemical dosimeter for using in radiation processing of agricultural products. Its simple synthesis method as well as low cost ...
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In this paper, the spectrophotometric properties of a colored Nickel-based solution complex (Nickel nitrate hexahydrate and Methyl Orange (MO)) were investigated as a stable chemical dosimeter for using in radiation processing of agricultural products. Its simple synthesis method as well as low cost made it a suitable dosimeter for use in radiation processing. The variation of absorbed dose was applied to measure the absorbed dose. The maximum absorbance for the solution was observed at 460 nm. This solution was irradiated at three different concentrations of Ni(No3)2.6H2O and MO by Co-60 gamma-ray. Also the variation of the absorbance as a function of PH of the solution was investigated. The results showed the solution absorbance decreases with an increase in doses, and this solution can be used as a routine dosimeter and has a linear response in the 50 to 1500 Gy range with acceptable stability in environmental conditions up to 40 days before and after irradiation.
Shahryar Malekie; Sedigheh Kashian; Seyed Musa Safdari; Morteza Akbari; Arjang Shahvar
Abstract
In this experimental work, Polycarbonate/Bismuth Oxide (PC-Bi2O3) nanocomposites were prepared in various concentrations of 0, 10, 30, and 50 wt% with thicknesses of 1 mm and irradiated by a pure beta-emitter source of Sr-90. To fabricate the electrodes, copper sheets with thickness of 100 µm were ...
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In this experimental work, Polycarbonate/Bismuth Oxide (PC-Bi2O3) nanocomposites were prepared in various concentrations of 0, 10, 30, and 50 wt% with thicknesses of 1 mm and irradiated by a pure beta-emitter source of Sr-90. To fabricate the electrodes, copper sheets with thickness of 100 µm were attached to the top and bottom surfaces of the samples using the silver paste. Then, electric current as the dosimetry response, was measured at various dose rates ranging from 30-102 mSv.h-1 at a fixed voltage of 400 V using an electrometer. Results showed that increasing the Bi2O3 wt% led to improvement in the dosimetry response linearly at various dose rates. Also, the amounts of sensitivities for the samples of 0, 10, 30, and 50 wt% were measured as 20.3, 19.8, 28.6, and 36.7 nC.mSv-1.cm-3, respectively. Regarding the mechanism of beta interaction with a polymer-heavy metal oxide nanocomposite, the Bremsstrahlung radiation can be considered as a dominant effect.
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.
