Cobalt-60 Gamma Radiation Research Articles

Inducing Sterility in Carolina Laurel Cherry Using Gamma Irradiation

Carolina laurel cherry (Prunus caroliniana) is native to the U.S. southeastern coastal plain from North Carolina westward to eastern Texas. The species has been planted extensively in the southeast as an ornamental tree or hedge. Unfortunately, carolina laurel cherry naturalizes readily and is now found in a variety of habitats, both natural and disturbed. Flowering occurs in the late winter/early spring before new leaves emerge and fruit ripens in the fall/winter. Fruit is eaten by migratory birds and seed is dispersed. Seedlings readily germinate in the understory of forests and landscapes in the spring. As there are a limited number of cultivars available, selections with improved form and sterility are needed for the landscape trade. In 2008, seed was collected and treated with Cobalt-60 gamma irradiation at rates ranging from 0 to 150 Gy. The lethal dose killing 50% of the seedlings (LD50) was between 50 and 100 Gy. Three sterile plants were selected in 2012 from the M1 (first generation of mutagen-treated seedlings) population totaling 62 seedlings. M2 (second-generation seedlings from M1 parents) seed was collected Fall 2012, and 1509 seedlings were grown to flowering size in containers. In 2014–15, 120 seedlings that showed no fruit production were planted in the field in Watkinsville, GA, for further evaluation. Ratings on field-grown plants in Dec. 2017 and 2018 showed that 73% and 78% of the plants, respectively, produced no fruit, whereas the remaining plants had minimal to heavy fruit set. Because carolina laurel cherry is andromonoecious, production of male and bisexual flowers was evaluated on 17 selections in 2018. Of 500 flowers evaluated per selection, the number of male flowers per plant ranged from 22 to 415 (4.4% to 83%). The number of racemes with all-male flowers on each selection ranged from 1 to 32. There were no significant correlations between the number of male flowers or number of all-male flowered racemes per plant and production of fruit. Approximately 5% of M2 seedlings remain seedless after 6 years of growth.

Radiochromic and radiofluorogenic solid state polymer dosimeter; a third signal: Electron Paramagnetic Resonance (EPR)

A solid-state polymeric dosimeter has been developed. The solid-state dye-doped polymeric dosimeter comprises the photo-curable polymer materials Poly(ethylene glycol)-diacrylate (PEGDA) and 2-Hydroxyethyl-methacrylate (HEMA) and the radiochromic leuco-dye 4,4′,4″- Triamino-triphenyl –acetonitrile. Using a photo-curable polymer blend facilitates a tight control of the polymerization process and hence the properties of the solid-state dosimeter. The radiation sensitive leuco-dye responds to ionising radiation by forming a stable free radical – a triphenylmethyl dye. This free radical has strong colour, and is fluorescent because it is dissolved in the solid polymeric material. Both physical properties can be measured optically. The free radical, however, provides a third signal as it is paramagnetic and hence can be detected by means of Electron Paramagnetic Resonance (EPR) spectroscopy. The EPR signal makes it possible to measure the radiation-induced free radical signal free from optical artefacts of the polymer material. Results from irradiations using a low-dose-rate cobalt-60 gamma irradiator shows an EPR signal measured using a Bruker EMX EPR spectrometer for the solid polymeric dosimeter, whose peak-to-peak amplitude is linear with the dose in the medical dose range and saturates for higher doses (100 Gy).

Effect of cobalt-60 gamma radiation on total hemocyte content and biochemical parameters in Macrobrachium rosenbergii (De Man, 1879)

Purpose: The effect of low level cobalt-60 (60Co) gamma radiation on the freshwater prawn Macrobrachium rosenbergii was evaluated by observing their hemocyte counts and biochemical parameters.Materials and methods: Prawns were exposed to 3, 30, 300 and 3000 milligray (mGy) dose levels and their tissues of gills, hepatopancreas and muscle were analyzed.Results: The results showed that the number of hemocytes in the hemolymph and concentrations of protein and carbohydrate were significantly reduced in irradiated groups than compared to the control prawn. Increased aspartate transaminase (AST), alanine transaminase (ALT), lactate dehydrogenase (LDH), alkaline phosphatase (ALP), Acetyl choline esterase (AChE) in the irradiated groups reflects tissue damage.Conclusions: Hence, this study concludes that even low level of ionizing radiation (60Co gamma) can cause acute damages in gills, hepatopancreas and muscles in irradiated groups.Highlights60Co exposures effect the THC and biochemical of prawn M. rosenbergii.Different dose levels such as 3, 30, 300 and 3000 mGy.Biochemical parameters serve as reliable indicators of physical status of organism.Self-regulating mechanisms might be the reason for preventing from the lethality.Suggested that nuclear industries should manage below 3 mGy.

Enhanced Survival in Mice Exposed to Ionizing Radiation by Combination of Gamma-Tocotrienol and Simvastatin.

Ionizing radiation exposure is a major concern for active military service members, as well as civilian population. Considering that the exposure is not predictable, it is imperative that strategies to counteract radiation damage must be discovered. Recent in vitro studies performed in our laboratory demonstrated that the vitamin E analog gamma-tocotrienol (GT3) in combination with cholesterol-lowering drugs (Statins), synergistically induced endothelial thrombomodulin, an anticoagulant with radio-protective efficacy. It was hypothesized that the combination of treatment with both GT3 along with Statins would provide better radiation protection in vivo than each drug individually. CD2F1 mice were injected subcutaneously with either vehicle or single dose of GT3 (200 mg/kg body weight) 24 hours before irradiation followed by oral or subcutaneous administration of various doses of simvastatin (25, 50, and 100 mg/kg body weight) before exposure to lethal doses (11.5 and 12 Gy) of Cobalt-60 (60Co) gamma-irradiation. The combined treatment group exhibited enhanced radiation lethality protection substantially, accelerated white blood cell recovery, and augmented restoration of bone marrow cellularity when compared to the animals treated with either drug exclusively. This information clearly suggests that combined treatment could be used as a safeguard for military personnel from exposure to harmful ionizing radiation.

Analyzing the Effects of Gamma Radiation (Cobalt-60) on the Shelf Life and Nutritional Quality of Carrot (Daucus Carota): A Review

Carrot is recognized as a most nutritious vegetable since it contains essential nutrients, vitamins, fibers and minerals required for normal growth and development of all living beings. The quality of vegetables is affected during storage due to ethylene production, respiration, transpiration, growth, development, compositional changes, physiological breakdown, physical damage and pathological breakdown. Under optimal storage conditions carrots can be preserved for 6–8 months without affecting any quality attributes, only if they are not infected by microorganisms producing storage diseases. Internationally, gamma radiation (60Co and 137Cs) has been proved as a safe and effective technology in extending the shelf life of fresh products. This technology further inhibits the sprouting of vegetables, the growth of pathogens and insects and also sterilizesvegetables and fruits. Gamma irradiation is more effective in the preservation of carrots as compared to the traditional preservation methods including pasteurization, freezing, chemical, refrigeration, or canning processes. Gamma radiation can enhance the trade opportunity and export quality of fruit and vegetables produced in Pakistan. Cobalt-60 gamma irradiation has no undesirable side effects on food and don’t cause any change in physico-chemical properties including the nutritional content of the treated product. It is practical in the conditions existing in the country. In Pakistan, food can be stored by incorporating gamma irradiation practically and economically under specific conditions. Hence, radiation is a promising technique for the extension of shelf life and it can contribute towards the economic growth of the country by exporting good quality carrots.

Evaluation of dosimetry a performance parameter for a homemade farmer-type ionization chamber according to IEC60731

Introduction: Due to its simplicity, fast response and high reliability, ion chamber detectors are one of the most suitable dosimetry instruments for X and gamma rays. The dosimeter of photon beams, which used in radiotherapy centers, requires high accuracy and should pass requirements of IEC 60731 standards. About 80 percent of the IEC 60731 standard tests such as stability, leakage current, the dose-response linearity, repeatability and resolution were assessed and the results were compared with the values reported by the standard. All tests were carried out on the PTW-30001 Farmer-type chamber and the response was compared with the manufactured chamber. Materials and Methods: In this study, according to the IEC 60731, IAEA guidelines and standards, using Cobalt-60 gamma radiation, the dosimetric and functional parameters of an ionization cavity detector of a cylindrical Farmer-type with sensitive volume of 0.6 cc, (homemade 0.6 cc Cylindrical Ionization Chamber), compared and calibrated against the calibrated reference Farmer chamber response (PTW-30001). Results: By applying minimum dose, leakage current was ±0.35 % and It was reduced by less than 1 % after radiation exposure. The percentage change in stability was ±0.3 %. Angular dependency in the chamber response was +0.2 %. Temperature effect on chamber reading was +0.2 % and the repeatability error was ±0.2 %. Conclusion: Unlike a simple look, Farmer-type chambers have their own technical complexity and cannot easily be used as a dosimeter by doing a few simple tests. Therefore, the IEC 60731 has been developed to address these complexities and introduce them as requirements for the application of an ionization chamber. The present work was a part of the project of manufacturing and commercializing a Farmer-type ionization chamber at the Nuclear Science and Technology Research Institute (NSTRI) in order to face the ahead challenges and try to resolve them. Most of the challenges that come from the technical knowledge and experience can be solved. All of the tests performed well with the standard requirements, but at the same time, compared to the reference ion chamber performance. There was negligible difference between the PTW reference chamber and the criteria required in the standard which demonstrates well-designed PTW chamber.

Plasma Derived Exosomal Biomarkers of Exposure to Ionizing Radiation in Nonhuman Primates.

Exposure to ionizing radiation induces a cascade of molecular events that ultimately impact endogenous metabolism. Qualitative and quantitative characterization of metabolomic profiles is a pragmatic approach to studying the risks of radiation exposure since it provides a phenotypic readout. Studies were conducted in irradiated nonhuman primates (NHP) to investigate metabolic changes in plasma and plasma-derived exosomes. Specifically, rhesus macaques (Macaca mulatta) were exposed to cobalt-60 gamma-radiation and plasma samples were collected prior to and after exposure to 5.8 Gy or 6.5 Gy radiation. Exosomes were isolated using ultracentrifugation and analyzed by untargeted profiling via ultra-performance liquid chromatography mass spectrometry (UPLC-MS) based metabolomic and lipidomic analyses, with the goal of identifying a molecular signature of irradiation. The enrichment of an exosomal fraction was confirmed using quantitative ELISA. Plasma profiling showed markers of dyslipidemia, inflammation and oxidative stress post-irradiation. Exosomal profiling, on the other hand, enabled detection and identification of low abundance metabolites that comprise exosomal cargo which would otherwise get obscured with plasma profiling. We discovered enrichment of different classes of metabolites including N-acyl-amino acids, Fatty Acid ester of Hydroxyl Fatty Acids (FAHFA’s), glycolipids and triglycerides as compared to the plasma metabolome composition with implications in mediation of systemic response to radiation induced stress signaling.

Use of irradiated elapid and viperid venoms for antivenom production in small and large animals

This work evaluated the feasibility of using toxoids obtained by gamma radiation in the production of antivenoms in small and large animals. Mixtures of African snake venoms from viperids or elapids were used. The viperid mixture contained the crude venom of five species of the genera Echis and Bitis, while the elapid mixture contained the crude venom of six species of the genera Naja and Dendroaspis. The viperid mixture had an LD50 of 1.25 mg/kg in mice, and the elapid mixture had an LD50 of 0.46 mg/kg. Both viper and elapid aqueous mixtures were subjected to Cobalt-60 gamma irradiation in three physical states: lyophilized, frozen and liquid. Radiation doses ranged from 0.5 to 100 kGy. The LD50s of the lyophilized and frozen mixtures of both viperid and elapid mixtures remained unaltered with radiation doses as high as 100 kGy; nevertheless, in the liquid state, doses of 3.5 and 5.5 kGy reduced the venom toxicity of both the viperid and elapid mixtures to 7.25 mg/kg and 1.74 mg/kg; less toxic by factors of 5.8 and 3.8, respectively. Groups of four rabbits and three horses were immunized with either irradiated or non-irradiated mixtures. In vitro and in vivo analysis of the rabbit and horse sera revealed that neutralizing antibodies were produced against both irradiated (toxoids) and native venom mixtures. None of the animals used in this study, either immunized with native venom or toxoids, developed severe local effects due to the application of venoms mixtures. Gamma-irradiated detoxified venoms mixtures, under well-controlled and studied conditions, could be a practical alternative for the production of polyvalent equine serum with high neutralization potency against snake venoms.

Thermoluminescence dosimetry properties and kinetic parameters of zinc borate silica glass doped with Cu2O and co-doped with SnO2

The glass phosphor thermoluminescence (TL) properties of zinc borate silica (ZBS:45ZnO-45B2O3–10SiO2) doped with various concentrations of Cu2O and then co-doped with various SnO2 was analyzed. The doped sample with 0.005% Cu2O concentration and co-doped with 0.1 mol% SnO2 have a higher TL response among the other concentrations for a delivered dose 50 Gy of Cobalt-60 gamma radiation. The obtained glow curve from the optimum doped and co-doped samples with 0.005% Cu2O and 0.1 mol% SnO2 concentrations are simple with single glow peak. The annealing procedure and heating rate are determined for both optimum samples. TL response within the dose range of 0.5–100 Gy, minimum detectable dose, reproducibility and fading are investigated. Based on analyses of glow curve, linearity, reproducibility, dose threshold, thermal fading, optical bleaching and activation energy frequency factor, the glass with co-doped 0.1 mol% SnO2 found to be suitable as a thermoluminescence dosimeter.

Experimental Investigation of Mechanical Performance and Printability of Gamma-Irradiated Additively Manufactured ABS

The work presented in this paper investigates the effects of gamma radiation on ABS in forms of irradiated 3D-printed parts, and irradiated filament used to later 3D-printed parts, using a cobalt-60 gamma irradiator. Tensile and flexural test samples were fabricated using off-the-shelf FDM 3D printers and irradiated at different dosages. Mechanical properties including elastic and flexure moduli, ultimate and flexural strength, % elongation at break, and surface hardness were evaluated, and results were compared to a control group. Evidence of cross-linking and chain scission and signs of possible oxidation of polymer caused by irradiation were found in both test groups which led to changes in mechanical properties. Moreover, it was found that ABS filament retains its printability after absorbing 15 kGy of gamma radiation and that its mechanical performance is very similar to those of irradiated samples at the same dose. Obtained results show promise for using ABS to fabricate sterile surgical instruments.

Evaluation of the effect of hesperidin on vascular endothelial growth factor gene expression in rat skin animal models following cobalt-60 gamma irradiation.

Skin is highly prone to radiation damage. Radiation burn is defined as damage to the skin or other biological tissues induced by radiofrequency or ionizing radiation. Vascular endothelial growth factor (VEGF) is a heparin-binded pro-angiogenic factor. Flavonoids belong to a family of polyphenol chemical compounds that are frequently present in fruits and vegetables. Hesperidin is an agent belonging to the flavonoid family. The aim of this study is to investigate whether hesperidin can affect the VEGF gene expression in rat skin following gamma irradiation or not. A total number of 36 male Sprague-Dawley rats were divided into three groups. First group: radiation group (n = 12), second group: radiation + hesperidin-treated group (n = 12), and third group: untreated control group (n = 12). The hesperidin administration dose was 100 mg/kg body weight. The rats received a 22 Gy single dose at a dose rate of about 0.3 Gy/min using a cobalt-60 external beam radiotherapy unit. The animals were euthanized 24 h postirradiation. VEGF gene expression data were analyzed using the equation 2-ΔΔCT, where ΔΔCT = (Threshold cycle [CT], of target gene - CT of housekeeping gene)treated group- (CT of target gene - CT of housekeeping gene)untreated control group. Glyceraldehyde-3-phosphate dehydrogenase gene was used as a housekeeping gene. VEGF gene in the radiation + hesperidin group overexpressed 25-fold relative to the control group. In addition, VEGF gene in the radiation group underexpressed 0.15-fold relative to the control group. When the three groups were compared relative to each other using the Kruskal-Wallis test, P < 0.001 was obtained. Based on the Mann-Whitney U-test, when all groups were compared to each in a binary model, P = 0.001 was achieved. These tests all showed statistically significant changes in VEGF gene expression. We can conclude that hesperidin is a potent angiogenic factor. Hesperidin as a radioprotector can initiate angiogenesis by VEGF gene induction. It may stimulate epithelialization, collagen deposition, and enhanced cellular proliferation. These changes can together accelerate wound healing, in particular, radiation-induced skin damage.

Application of gamma radiation and physicochemical treatment to improve the bioactive properties of chitosan extracted from shrimp shell

Abstract The aim of this study is to exploit a suitable chitosan extraction method from the chitin of indigenous shrimp shells by employing different physicochemical treatments and to improve different bioactive properties of this extracted chitosan (CS) by applying gamma radiation. Chitin was prepared from shrimp shell by pretreatment (deproteination, demineralization and oxidation). Chitosan was extracted from chitin by eight different methods varying different physicochemical parameters (reagent concentration, temperature and time) and assessed with respect to the degree of deacetylation, requirement of time and reagents. The method where chitin was repeatedly treated with 121°C for 30 min with 20 M NaOH, produced the highest degree of deacetylation (DD) value (92%) as measured by potentiometric titration, with the least consumption of time and chemicals, and thus, selected as the best suitable extraction method. For further quality improvement, chitosan with highest DD value was irradiated with different doses (i.e., 5, 10, 15, 20 and 50 kGy) of gamma radiation from cobalt-60 gamma irradiator. As the radiation dose was increased, the molecular weight of the wet irradiated chitosan, as measured by the viscosimetric method, decreased from 1.16 × 105 to 1.786 × 103, 1.518 × 103, 1.134 × 103, 1.046 × 103 and 8.23 × 102 dalton, respectively. The radiation treatment of chitosan samples increased the antimicrobial activity significantly in concentration dependent manner on both gram-positive (Staphylococcus aureus) and gram-negative (Escherichia coli) bacteria, as determined by the well-diffusion method. Four to five percent wet chitosan treated with a radiation dose range of 5.0–10.0 kGy rendered the highest antimicrobial activity with least energy and time consumption. Solubility, water binding capacity (WBC) and fat binding capacity (FBC) also improved due to irradiation of chitosan.

Irradiation grafting of natural rubber latex with maleic anhydride and its compatibilization of poly(lactic acid)/natural rubber blends

Maleic anhydride (MA) is an interesting monomer to be grafted onto natural rubber(NR) due to its potential as a compatibilizer of hydrophobic rubbers and polymers with higher polarity. So far, radiation grafting of MA onto NR in latex state has not been reported. In this study, the grafting of NR with MA in latex state was investigated by exposing the latex to cobalt-60gamma irradiation at a fixed MA content of 9% and a varied absorbed doses from 2 to 10kGy. The FTIR spectrometer, 1H NMR spectrometer and gel content analysis have confirmed successful grafting of MA onto NR after irradiation. The grafted NRs were then used to increase the compatibility and the impact property of PLA/NR blends. It was found that the highest impact strength of the blends was achieved when the grafting was carried out at the absorbed dose of 4kGy.

Morphophysiological and biochemical alterations in Ricinus communis L. seeds submitted to cobalt60 gamma radiation.

This study aimed to evaluate the radiosensitivity of castor bean seeds after applications of different doses of Cobalt60 gamma radiation. Seeds were pre-soaked for 24 hours in distilled water and then irradiated with 50, 100, 150, and 200 Gy, except the control. Sowing was performed in trays, which contained soil as substrate and were maintained in a greenhouse. The electrical conductivity, emergence, emergence speed index, growth parameters and activities of antioxidant enzymes (superoxide dismutase, ascorbate peroxidase, and catalase) were evaluated in the leaves and roots of castor bean seedlings. Gamma radiation did not affect the electrical conductivity of the seeds; however, at a dose of 200 Gy, the emergence and emergence speed index of the seedlings was negatively affected. An analysis of the morphophysiological parameters revealed a reduction in seedling size as the radiation dose increased. There was a significant increase in superoxide dismutase and ascorbate peroxidase activities at higher radiation doses in the leaves, but not in roots. Thus, the analysis of all the variables suggests a response pattern as to the morphophysiological and biochemical changes of castor bean seedlings due to the increase of gamma radiation, which may serve as a tool for generating greater genetic variability.

Commissioning dosimetry and in situ dose mapping of a semi-industrial Cobalt-60 gamma-irradiation facility using Fricke and Ceric-cerous dosimetry system and comparison with Monte Carlo simulation data

Characterization of a 90 kCi (3330 TBq), semi-industrial, cobalt-60gamma irradiator was performed by commissioning dosimetry and in-situ dose mapping experiments with Ceric-cerous and Fricke dosimetry systems. Commissioning dosimetry was carried out to determine dose distribution pattern of absorbed dose in the irradiation cell and products. To determine maximum and minimum absorbed dose, overdose ratio and dwell time of the tote boxes, homogeneous dummy product (rice husk) with a bulk density of 0.13g/cm3 were used in the box positions of irradiation chamber. The regions of minimum absorbed dose of the tote boxes were observed in the lower zones of middle plane and maximum absorbed doses were found in the middle position of front plane. Moreover, as a part of dose mapping, dose rates in the wall positions and some selective strategic positions were also measured to carry out multiple irradiation program simultaneously, especially for low dose research irradiation program. In most of the cases, Monte Carlo simulation data, using Monte Carlo N-Particle eXtended code version MCNPX 2.7., were found to be in congruence with experimental values obtained from Ceric-cerous and Fricke dosimetry; however, in close proximity positions from the source, the dose rate variation between chemical dosimetry and MCNP was higher than distant positions.

Response of Normal Cells Following Multiple Radiation Exposure under Radiotherapy Setting

Radiotherapy is an established approach for killing of tumour cells. During the process, most of the normal cells also get affected due to direct exposure or by bystander effects. To measure the damage pattern in healthy cells, a pilot study was designed under radiotherapy settings. Right leg region of Strain ‘A’ male mice was locally exposed to Cobalt60 gamma radiation with a dose of 2 Gy/ day for 5 consecutive days. After completion of each fraction, blood haematology and γH2AX studies were performed at 1 h time point in blood and bone marrow cells. Chromosomal aberration study in bone marrow was carried out at 24 h post irradiation of each fraction for evaluation of DNA damage. γH2AX and chromosomal aberration were found significantly (p&amp;lt;0.001) increased with each consecutive dose upto 4th fractions. Blood hematology showed a linear reduction in total WBC counts which included the reduction in lymphocytes and increased granulocytes with each passing dose up to 4th fraction. However, non significant damage (p&amp;gt;0.05) for all parameters have been observed for 4th and 5th split doses. The study indicated that repeated exposure leads to damage fixation in normal cells, possibly indicating a state of adaptation.

Effects of gamma irradiation on the mechanical and thermal properties of cyanate ester/benzoxazine resin

In this study, thermosetting resin blends composed of cyanate ester (CE) and benzoxazine (BOZ) were prepared and then subjected to gamma-ray irradiation with doses up to 1000kGy from a cobalt-60gamma irradiator. The objective of this present study was to experimentally assess the effect of γ-ray irradiation on the mechanical behaviour, chemical structure and thermal properties of the CE/BOZ resin blends by the bending test, dynamic mechanical analysis (DMA), scanning electron microscopy (SEM), Fourier Transform Infrared (FTIR) and thermogravimetric analysis (TGA). The results showed that at a low radiation dose (250kGy), the flexural strength and modulus, thermal stability, storage modulus and glass transition temperature of the CE/BOZ resin gradually declined first, then sharply increased when the radiation dose increased to 500kGy and finally slightly dropped at the end with a dose of 1000kGy. The decrease in the aforementioned properties could be ascribed to the degradation process including the rupture of chemical bonds and scission of molecular chains of the CE/BOZ resin blends, which were confirmed by the FTIR and SEM. However, a significant improvement in the thermal and mechanical properties of the blend was found when the radiation dose increased to 500kGy.

Tolerance of holographic polymer-dispersed liquid crystal memory for gamma-ray irradiation.

The radiation-hardened characteristics of holographic polymer-dispersed liquid crystal (HPDLC) memory are discussed in the application for an optically reconfigurable gate array. The radiation experiments are conducted using a cobalt 60 gamma radiation source to examine the tolerance of a 100Mrad total ionizing dose for the HPDLC memory. The optical properties are compared in the conditions before and after gamma-ray irradiation for the fabricated HPDLC gratings. The effects of gamma-ray irradiation on the internal grating structure are also investigated by polarization optical microscopy and scanning electron microscopy observations. The HPDLC memory irradiated by a 100Mrad total ionizing dose demonstrates the implementation of the optical reconfiguration in a gate-array VLSI.

Effect of Cu2O on the thermoluminescence properties of ZnO-B2O3–SiO2 glass sample

The thermoluminescence properties of optimum zinc borate silica ZBS glass sample doped with various concentrations of Cu2O were studied. TL response is enhanced by doping ZBS glass samples with different concentrations of Cu2O. The sample with 0.005% Cu2O concentration has a higher TL response among the concentrations for a delivered dose 50Gy of Cobalt-60gamma radiation. The obtained glow curve from the optimum sample with 0.005% Cu2O concentration is simple with single glow peak. The annealing procedure and heating rate are determined. TL response within the dose range of 0.5–100Gy, minimum detectable dose, reproducibility and fading are investigated. The results show that the new glass sample has good TL properties for radiation dose evaluation.

Impact of Cobalt-60 Gamma Radiation Source on Electronic Devices using Geant4

This paper discusses the evaluation of performance of the Atmel Atmega328 under exposure of Cobalt-60(Co-60) source. Geant4 software is used to simulate the passage of particles through matter and calculate the absorb dose rate using Monte Carlo Methods. In the simulation using the Geant4 software, we vary the distance of IC from the source. Experiments also was conducted to measure radiation level of actual Cobalt-60 source using Atmel Atmega328 based Geiger Muller Tubes sensor. The result of the simulation experiments were discussed based on the inverse square law theorem. Following the advantages and limitations of this paper, some recommendations for future researchers were also presented.