60Co Gamma Research Articles

Gamma ray irradiation on Swiss cheese estates (Monstera adansonii): growth, development, and variation

Purpose Swiss Cheese (Monstera adansonii) is an ornamental plant valued for its exotic leaves with openings and for the variety of colors. The technique of controlled exposure to gamma radiation was investigated to induce variegation (color change) in the leaves of this plant. Materials and methods Monstera adansonii cuttings were irradiated with different doses of radiation with 60Co gamma rays (0, 1, 5, 10, 15, and 20 Gy) and evaluated for size, color, health, and growth. Results Cuttings irradiated with 1 and 5 Gy exhibited temporary variegation in leaf color, but did not maintain these characteristics over time. Cuttings with higher doses of radiation (10, 15, and 20 Gy) did not survive well and showed a reduction in growth, number of leaves, health, and sprouting rate. Conclusions This research concludes that gamma radiation can affect the development of cuttings and shows the potential to induce variegation at lower doses, but more studies and prolonged observation are needed to determine whether this technique can produce variegation in a consistent and lasting way in M. adansonii. Therefore, although promising initial results have been observed, it is premature to state that gamma radiation is an effective method for inducing variegation in this plant.

Investigation of thermal, acoustic, mechanical, and radiation shielding performance of waste and natural fibers

It is crucial to address two pressing global issues, energy shortage and environmental pollution, when producing building insulation materials. Using waste and natural fiber groups can be part of the solution. The insulation material was produced using pumpkin fiber, chicken fiber, cotton waste, vermiculite, and epoxy as binders. The samples were tested for thermal conductivity coefficient, ultrasonic sound transmission rate, density, water absorption rate, compressive and bending strength, and fire resistance at temperatures of 75, 100, 125, and 150C. The samples produced using natural and waste materials yielded a thermal conductivity value of 0.041 W/mK, an ultrasonic sound transmission speed of 0.25 km/s, a compressive strength value of 1.57 MPa, and bending strength values of 0.91 MPa. It has been clearly demonstrated that, with its low volume loss, it can serve as an alternative to the EPS-XPS types available in the market. Furthermore, the linear attenuation coefficients (LAC) were examined to obtain radiation shielding properties of the samples at 1173 and 133 keV energies using a 60Co gamma source. Also, LAC values determined between 0,1167 ± 0,0452 cm−1-0,2315 ± 0,0065 cm−1 for 1173 keV and 0,1042 ± 0,0488 cm−1 - 0,2141 ± 0,0062 cm−1 for 1333 keV. Accordingly, it has been revealed that waste compositions are effective in protecting against radiation.

TL response of Sm-doped MgO to 60Co gamma radiation

The thermoluminescent (TL) response of MgO doped with different rare earths was investigated. The TL material was synthesized by the solution combustion method and sintered at 1173 K; the obtained powders were prepared in pellet form. Before irradiation, the dosimeters were annealed at 623 K for 30 minutes to eliminate any TL signal generated during their manufacture. Independent tests were performed doping the MgO with Tm, Dy, Ce and Sm. The highest TL response was found for Sm-doped MgO (MgO:Sm) reaching the highest sensitivity for 0.4 mol% of Sm. For this sample, the TL response showed linearity from 0.001 to 500 Gy of 60Co gamma radiation. The lower detection limit was found to be equal to 1.17 μGy. The sensitivity of the MgO:Sm prepared dosimeter was approximately 10% the sensitivity of the commercial TLD-100. The TL signal fading was found to be 6% after one month. The deconvolution of the glow curve showed a symmetric peak with a general order kinetics, b, centered at 474 K. These results suggest that this new TL material could be a promising detector to use in diverse dosimetry applications.

Modification of activated carbon through chemical-physical activation method with KOH and 60Co gamma irradiation from banana leaf waste

Abstract Until now waste is still a problem in many big cities in Indonesia. In addition, the amount of waste increases as the population increases. Banana leaf waste is no exception, which is included in other types of waste, which accounts for 6.33% of the total waste in Indonesia in 2022. Utilization of banana leaf waste as a raw material for activated carbon production can also be an alternative to reducing the amount of wasted banana leaf waste because they contain various kinds of organic compounds. Activated carbon is widely used as an adsorbent in various sectors, especially in the industrial sector. Production of activated carbon must go through an activation process to enlarge the surface pores either chemically or physically, or even both. This study aims to compare the results of activated carbon surface area and functional groups using the chemical-physical activation method from banana leaf biomass raw materials with KOH and gamma irradiation at various doses. The research method used is an experimental method consisting of 4 stages: dehydration, carbonization, activation, and characterization. The research was started by dehydrating the leaves and continued with the carbonization stage at 350°C for 30 minutes. Carbon was divided into four samples that consisted of 1 blank and 3 test materials that activated with 30% (w/v) KOH solution for 24 hours and gamma-irradiated with a dose of 10, 30, and 50 kGy. Results were characterized using FTIR and BET. The effect of gamma 60Co irradiation on the activated carbon material from banana leaf waste can increase the peak transmittance value of the activated carbon functional group due to the formation and reaction of free radicals on its surface. Increase in the surface area (from 6.504 to 24.04 m2/g) is also associated with an increase in the absorbed dose due to the formation of more free radicals. However, the surface area obtained is not as expected due to the possibility of pore blockage and excessive activation time, which causes the surface area of the material to be small.

Synthesis of Activated Carbon from Banana Peel Biomass Using NaCl and Gamma Co-60 Irradiation

Abstract Indonesian Institute of Sciences (LIPI) stated that the potential for biomass resources in Indonesia is estimated at 49,810 MW originating from plants and waste in 2013 and of course it continues to grow, considering that the source of biomass is from nature. An example of biomass is banana peel. This banana peel can be used as activated carbon. Known from several journals that activated carbon can be applied in various ways such as being a hydrogen storage material, water purification, etc. There are three steps to synthesis activated carbon that divided into initial steps, the first is synthesis of activated carbon, which begins with drying banana peels and then cutting them, then drying them below the sun. Then it is carbonized at 400°C and immersed chemically activated with a salt activator, NaCl. The second step is combining or modifying activated carbon via gamma irradiation and the last step is characterization using BET to know surface area and FTIR to analyze the functional group. The result shows that as an effect of the modification of gamma irradiation doses by 10 kGy, 30 kGy and 50 kGy on activated carbon banana peel, the FTIR spectra increased markedly by the widening of the last stretch. Modification the banana peel with gamma irradiaton Co-60 is the surface area is increase than those without irradiation, but not significantly. It occurred due to the process of carbon degrade due to gamma irradiation of Co-60 can degrade cellulose structures.

Characterization of ferrous-xylenol orange-polyvinyl alcohol gel for gamma dosimetry using spectroscopy

Abstract Fricke gel dosimeters are appropriate candidates for gamma dosimetry. Polyvinyl alcohol Fricke gel dosimeters are the most recent introduced gel dosimeters which have low ion diffusion. In this work, samples of ferrous-xylenol orange-polyvinyl alcohol gel dosimeters were prepared and characterized using optical spectroscopy. Using win XCOM program and the elemental composition of the gel, the mass attenuation coefficients for photons were evaluated. The results exhibited that the prepared gel is the nearly radiological blood-, soft tissue- and water-equivalent. The 60Co gamma cell unit was used to irradiate the gel samples. A dose range response was found linear from 10 to 30 Gy and suitable for blood irradiation dosimetry. Additionally, the gel response good repeatability was confirmed by the coefficient of variation calculations. Furthermore, chemical yield of the gel was estimated to be 34.6. The good characteristics of the prepared gel make it appropriate for dosimetry of blood irradiators.

Thermal properties and FTIR spectroscopy: Edible film of chitosan-glycerol utilizes gamma irradiation

Abstract As chitosan and glycerol are mixed, they form a polymer blend that can be processed into edible films, or other plastic-like materials. Chitosan-glycerol mixing generates properties of edible, which means it can break down into non-toxic components over time through natural processes, reducing its environmental impact. In this work, edible film is contained chitosan-glycerol edible films were prepared by evaporation casting from its solution. Edible films were placed on the polyethylene packages and irradiated by Co-60 gamma rays on various radiation doses. After gamma irradiation process, edible films were stored at ambient temperature. To conduct a more in-depth analysis, the edible films undergo characterization using fourier transform infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC). Additionally, effects of gamma irradiation are shown in shifts of C-O stretching shifted to 1045-1080 cm−1. The N-H and O-H bond became narrow after irradiation of edible films as a higher gamma irradiation dose. Gamma irradiation increased the melting point of chitosan-glycerol mixtures from 173.4 °C to 190.2 °C endothermic peak. The findings revealed that gamma radiation led to enhanced molecular interaction between chitosan and glycerol, thereby influencing the thermal properties of edible films.

Effect of gamma-radiation on the transmission and return losses of FC/APC connectors

The Fibre Optics Current Sensor (FOCS) installed at ITER will use optical fibres to perform plasma current measurements based on the Faraday effect. A connection between the sensing fibre placed on the Vacuum Vessel and the fibre guiding the signal to the data-acquisition hardware will be required. Because of practical reasons, this link contains FC/APC connectors, which guarantee the low return loss required for normal operation of the FOCS. The connectors will be located in the port cell area and will be subject to high levels of nuclear radiation. Radiation may influence both transmission and return losses of the FC/APC connectors and, as a result, degrade the FOCS performance. To address the problem, several FC/APC connectors were exposed to Co60 gamma radiation up to a 550 kGy dose. Transmission through the connectors was monitored during irradiation. The return loss of mated FC/APC connectors was measured before and after irradiation. It was found that radiation-induced changes of both transmission and reflection parameters are acceptable for the FOCS at ITER.

Effects of athermal carrier injection on Co-60 gamma-ray damage in SiC merged-PiN Schottky diodes

Co-60 gamma irradiation of SiC merged-PiN Schottky (MPS) diodes up to fluences of 1 Mrad (Si) produces increases in both forward and reverse current, with less damage when the devices are biased during irradiation. Subsequent injection of minority carriers by forward biasing at 300 K can partially produce some damage recovery, but at high forward biases also can lead to further degradation of the devices, even in the absence of radiation damage. Recombination-enhanced annealing by carrier injection overall is not an effective technique for recovering gamma-induced damage in SiC MPS diodes, especially when compared to other near athermal methods like electron wind force annealing.

Preparation and properties of strong gamma ray shielding and irradiation resistant glass

CeO2 doped lead silicate glasses samples were prepared by high temperature melting method. The structural, thermal and optical properties of the glasses were characterized by density, expansion coefficient, XPS and ultraviolet-visible spectroscopy. Additionally, the related theoretical work was carried out for verification. The changes in structure and optical properties of the glass before and after irradiation were investigated. The influence mechanism of different content of CeO2 (PbO) on the structure and properties of shielding glass was discussed. By comparing the three transmittance conversion formulas, it is found that the characteristic coefficient can be further calculated if the transmissivity with varied thicknesses is known. This coefficient method allows for accurate calculation of transmittance for glasses with arbitrary thicknesses while demonstrating experimental validation. The accuracy improves as more measured values of transmittance for glasses with different thicknesses are obtained and as more iterations of characteristic coefficients are performed. This method is suitable for both scientific research and production practice. The test results show that the transmittance of the glass with 45 wt% PbO and 2 wt% CeO2 content is above 60 % in the wavelength range of 400–800 nm before irradiation and decreased less than 10 % after irradiation. The measured shielding rate of 60Co gamma rays can reach more than 51 %. The calculated transmittance of 300 mm thickness glass is greater than 50 %. The superior gamma ray shielding capability along with its radiation resistance make this glass provide key support for window materials used in various fields such as nuclear industry, aerospace, military and medicine.

Structural evolution of zirconium diboride under gamma irradiation and thermal annealing

Understanding the thermal properties and enhancing the performance of zirconium diboride (ZrB2) under extreme conditions is crucial, especially given its role as a burnable absorber in nuclear fuel pellets and its potential applications in accident-tolerant fuels. This study explores the structural alterations of ZrB2 crystals induced by gamma irradiation and subsequent thermal annealing. ZrB2 crystals were exposed to absorption doses of 300 kGy, 1000 kGy, 1500 kGy, and 3000 kGy using a 60Co gamma source, followed by thermal treatment at 1173 K under vacuum conditions. Also, Monte Carlo simulations were utilized to analyze the energy deposition and distribution of gamma quanta within the material during irradiation, highlighting Compton effects up to 0.23 MeV. X-ray diffraction analysis elucidated the impact of gamma radiation on ZrB2 crystal lattice parameters, space group, and volume expansion coefficient. Post-irradiation analysis revealed a maximum degree of amorphization and investigated mechanisms governing lattice parameter expansion. Thermal annealing at 1173 K significantly enhanced crystallinity, reducing amorphization to 0.2 % at an absorption dose of 3000 kGy and facilitating the restoration of the crystal's columnar structure. This comprehensive investigation provides insights into the intricate interplay between gamma irradiation, thermal processing, and resulting structural changes in ZrB2 nanocrystals, essential for applications in radiation-exposed environments.

Structural, thermo-mechanical, optical and gamma-ray shielding properties of lead-free BaO–ZnO–B2O3–SiO2 and lead-based PbO–Bi2O3–K2O–SiO2 glasses

Lead-free BaO–ZnO–B2O3–SiO2 glass (BZBS) and lead-based PbO–Bi2O3–K2O–SiO2 glass (LS) were synthesized by melt quench technique. Glass samples were irradiated using 60Co gamma source up to 50 kGy dose to study the changes in structural, thermo-mechanical, optical and gamma ray shielding properties. Measured density values of both the glasses were greater than 4.0 g/cc. X Ray Diffraction (XRD) studies confirmed amorphous nature of prepared glasses before and after gamma irradiation. The structural changes induced by gamma irradiation were also investigated using Raman, Positron annihilation lifetime spectroscopy (PALS) and Electron Paramagnetic Resonance (EPR) spectroscopy. PALS data revealed increase in free volume/voids after irradiation. Defect studies carried using EPR spectroscopy confirmed formation of electron trap centre in BZBS glass, whereas in LS glass in addition to the electron trap centers, non-bridging oxygen hole centers (NBOHC) and peroxy radical defects were also observed. Investigations on thermo-mechanical properties demonstrated higher glass transition temperature (Tg), hardness and modulus of elasticity values for BZBS glass as compared to the LS glass, which were found to be decreased after irradiation because of radiation induced defects. Visible transparency and band gap for BZBS glass were found to be higher than that in LS glass. After irradiation, colour change, reduction in transparency as well as band gap, and red shift in absorption edge were observed due to the formation of defects in both the glasses. The values of radiation induced absorption (α) at three different visible wavelengths have been determined for 50 kGy dose using UV–Vis transmission data. Analysis of refractive index data showed around 12 % reflection losses for both the glasses. Annealing of irradiated samples using UV light source showed significant improvement in transparency. Linear attenuation coefficient (LAC) was calculated using XCOM program and experimentally measured using 60Co 1.33 MeV gamma ray. Linear attenuation coefficient of BZBS glass was around 0.20 cm−1 whereas for LS glass value was 0.24 cm−1. Half value layer thickness of prepared glasses was also compared with available standard materials and it was found that prepared glasses may be suitable for shielding of high energy gamma rays.

Behavior of uranium(VI) in the presence of a geomaterial: an aquifer sediment

Sediments from aquatic environments can be contaminated with uranium from natural and anthropogenic sources; the behavior of U(VI) was investigated in two natural (SPT and DS) and gamma-irradiated (SPT-I) aquifer sediments in batch systems. Sediments were characterized, and quartz, albite, and kaolinite were mainly found in both sediments by X-ray diffraction. The points of zero charge were 5.4, 5.3, and 5.5, and the organic matter percentages were 48.0, 46.0, and 4.7% for SPT, SPT-I, and DS, respectively. Uranyl nitrate solutions were put in contact with each sediment considering different parameters (pH, contact time, initial concentration of uranium, and temperature). DS sediment did not adsorb any quantity of uranium at different pH values; SPT and SPT-I, attained the highest q e values at pH 3.5–4. The results show chemisorption on homogenous materials and endothermic processes. Desorption behavior of U(VI)/SPT showed a hundred percent desorption with nitric acid and humic acid solutions; in the last case, it is due to the high stability constant of the complex of uranium with the humic acids. The results help to understand the contamination and decontamination processes of sediments with uranium, the bioavailability of uranium, the ecological risk of U-contaminated sediments, and remediation. Doses of 1 MGy of Co-60 gamma radiation did not affect the uranyl ions behavior in the aquifer sediment.

Impact of Co-60 γ-ray irradiation on the cross-linking and stability of fish collagen: Structural changes and digestibility

Irradiation can promote the cross-linking of collagen to enhance its biological properties, but the molecular changes in irradiated collagen have few been investigated. This study aimed to explore the impact of irradiation treatment on the molecular structure stabilization and cross-linking degree of skin collagen. The results showed that collagen in solution was more susceptible to Co-60 gamma irradiation than that in fish skin and in sponge forms. The solubility of collagen in solution decreased by more than 80% and the carbonyl content increased by more than 4 times compared with the control group after 12 kGy irradiation. Spectroscopic analysis and sodium dodecyl sulfate - polyacrylamide gel electrophoresis (SDS-PAGE) showed that collagen in solution was cross-linked, especially at high irradiation doses. However, the triple helical structure of skin collagen and collagen sponge remained intact. Furthermore, irradiation also reduced the sensitivity of collagen to collagenase. Gastrointestinal digestion results showed that the antioxidant activity of collagen increased at 1–3 kGy doses and decreased at 9–12 kGy doses. Collagen irradiated at high doses (9–12 kGy) was more difficult to digest and had a larger average particle size. This study provides a potential new approach for the preparation of stable fishery-derived collagen with excellent antioxidant activity and resistance to digestion by irradiation treatment.

Influence of 60Co gamma radiation on the structural, morphological and optical properties of hydrothermally synthesized MoO3-CeO2 nanocomposite.

The influence of 60Co gamma radiation on Molybdenum Oxide-Cerium Oxide (MoO3-CeO2) nanocomposite is investigated in the present study. The MoO3-CeO2 nanocomposite was synthesized by conventional hydrothermal route. Ammonium hepta molybdate tetrahydrate [(NH4)6Mo7O24.4H2O] and cerium nitrate [Ce (NO3)3.4H2O] were used as the precursors. The composite was subjected to high energy gamma irradiation for different doses of 50, 100 and 150 kGy using 60Co gamma irradiation chamber. The structural study was carried out using X-ray diffraction, the morphological studies were carried out using scanning electron microscopy and ultraviolet-visible spectroscopy was carried out to study the optical properties before and after irradiation. The crystallite size was found to increase with increasing doses of gamma irradiation. The morphology of the samples shows that the nanoparticles tend to agglomerate with increasing doses of gamma radiation. The energy bandgap of the MoO3-CeO2 nanocomposite was calculated before and after irradiation and found to decrease with increasing doses of irradiation upto 100 kGy and then increases for 150 kGy.

An investigation of 60Co gamma radiation induced damage in N-channel MOSFETS at cryogenic temperature.

N-channel depletion metal oxide semiconductor field effect transistors (MOSFETs) were irradiated with 60Co gamma radiation in the dose range of 100 krad to 6Mrad at cryogenic (77K) and room temperatures (300K). The MOS devices irradiated at 77K and 300K were characterized at 77K and 300K respectively. The different electrical parameters of MOSFET such as threshold voltage (Vth), density of interface trapped charges (ΔNit), density of oxide trapped charges (ΔNot) and mobility of the charge carriers (μ) were studied as a function of total dose. A considerable increase in ΔNit and ΔNot and decrease in Vth was observed after irradiation. The 77K irradiation results were then compared with 300K irradiation results and found that the degradation in the electrical characteristics is more for the devices irradiated at 300K.

60Co gamma radiation effects on NPN transistor at cryogenic temperature.

The 60Co gamma radiation effects on the DC electrical characteristics of silicon NPN transistor were studied in the dose range of 100krad to 6Mrad at room temperature (300K) and cryogenic temperature (77K). The measurements were carried out at both 300 and 77K temperature. The electrical characteristics such as Gummel characteristics, excess base current (ΔIB), current gain (hFE), transconductance (gm) and output characteristics were studied in situ as a function of total dose. The results show that there is a considerable degradation in the electrical parameters of the device irradiated both at 300 and 77K as a consequence of increase in excess base current (ΔIB) because of the formation of generation and recombination centers in the emitter-base spacer oxide (SiO2). At cryogenic temperature irradiation, the degradation in electrical characteristics is less because of the physical phenomena such as carrier freezeout effect, decreased recombination rate, reduced charge yield, decreased electron mobility, etc.

Effect of 60Co gamma irradiation on hydrothermally synthesized Ga2O3-Tio2 nanocomposites.

The effect of 60Co gamma irradiation on gallium oxide and titanium oxide (Ga2O3-TiO2) nanocomposites are investigated in the present study. The Ga2O3-TiO2 nanocomposite was synthesized by hydrothermal method at 120°C. The precursors for the synthesis consist of gallium nitrate anhydrous and titanium trichloride along with sodium hydroxide to achieve the pH of 9. The synthesized Ga2O3-TiO2 was subjected to 60Co gamma irradiation for different doses such as 25, 50 and 75kGy. The morphological, optical and microstructural characteristics were studied using scanning electron microscopy, UV-Visible spectroscopy, X-ray diffraction and Fourier transform infrared spectroscopy, respectively. The results shows that the gamma irradiation induces significant changes in the Ga2O3-TiO2 microstructure and there is increase in the grain size and bandgap of the nanocomposites.

Latent fingerprint imaging using irradiated novel mixed metal oxides (MXOY, M=Ba, Zn, Al, Ce) nanophosphor.

Latent fingerprint developed at the site of crime is considered as crucial physical evidence in forensic investigation. The mixed metal oxides (MXOY, M=Ba, Zn, Al, Ce) nanophosphor was synthesised by irradiating the precursor solution with 60Co gamma radiation followed by solution combustion method. The structural, morphological, optical characteristics and fingerprint imaging were studied using X-ray diffraction (XRD), scanning electron microscopy, UV-visible spectroscopy and powder dusting method, respectively. The XRD results revealed that the average crystallite size is found to be 30nm with the estimated bandgap of 3.18eV. The broadband UV exited luminescence of the phosphors was observed at λMax=330nm. The PL spectrum shows three emission bands at 432, 444 and 460nm that corresponds to blue regions, suggesting that the synthesised nanophosphor is a potential luminous material for latent fingerprinting and luminescent devices.

Study of the Adsorption/Desorption Behavior of Uranium in a Forest Soil

ABSTRACT The behavior of soluble uranium (VI) on the adsorption/desorption processes in the presence of a natural forest soil (FS) or a gamma-irradiated forest soil (FS-I) provides important knowledge on the fate and mobility of this element in contaminated soils and groundwater. Soil from a forest was irradiated with a dose of 1 MGy 60Co gamma radiation and was compared with natural soil to determine the behavior of U(VI) in these materials. Both natural and gamma irradiated soils were characterized by several physicochemical techniques. Kinetics, isotherms, effects of pH, U(VI) concentration, temperature, and stability of the U(VI)/adsorbents were considered. The equilibrium of adsorption processes U O 2 2 + /FS and U O 2 2 + /FS-I were achieved in 2 h, and the data were well fitted to the pseudo first (FS-I), pseudo second (FS), and Elovich models (FS): qe value was 14 mg g−1 for FS, slightly higher than 12 mg g−1 for FS-I. The isotherm data were well-fitted to the Langmuir and Temkin models for FS and FS-I, respectively. The processes of both materials are independent of the temperature between 30 and 50°C; however, they are sensitive to pH and U(VI) concentration. Furthermore, acidic media and complexing agents were good desorbents for U(VI) from the natural and irradiated soils.