Gamma-ray Dose Research Articles

OPTIMIZATION OF MUTAGEN DOSE FOR EARLY SEEDLING YIELD ASSOCIATED QUANTITATIVE CHARACTERS IN CANOLA GERM PLASM

Pakistan is facing vital shortage in supply of health promoting crops used as vegetable as well as oil source. Brassica napus (Canola) is such a rich crop that occupy an important position in the oilseed crops of world but unfortunately in Pakistan its germ plasm needs genetic improvement due to narrow gene pool. Mutagenesis is a powerful tool for introducing new alleles, therefore different doses of Gamma radiations (750Gy, 1000Gy, 1250Gy) and EMS (0.5%, 1.0% and 1.5%) were used to induce genetic diversity for early yield associated quantitative characters in two Canola genotypes (Hyola-41 and Shiralee). The data was recorded for days to flowering, days to maturity, plant height, number of branches per plant and pod length in M2 and M3 generation. Significant (p≤0.05) variations were observed for most of phenotypic parameters for both mutagens. The mean value of all the phenotypic parameters in M2 generation increased with moderate dose of EMS and Gamma rays in both genotypes as compared to respective controls. whereas in M3 generation both genotypes were more responsive to Gamma rays (1000 Gy) for all studied characters except early maturity in both tested genotypes. Heritability analysis exhibited high heritability and high genetic advance for most of the traits by moderate and highest does of Gamma rays, while reverse is true for EMS in both generations for Shiralee.

Design of Moderator Assemblies for Fast, Epithermal, or Thermal Neutron–Dominated n-γ Mixed Fields Using a D-D Neutron Source

The treatment field of boron neutron capture therapy (BNCT) is a n-γ mixed field. In the Osaka University BNCT project, a material-filtered radio-photoluminescence glass dosimeter (RPLGD) was proposed for the simultaneous measurement of neutron and gamma-ray doses. In this study, to validate the material-filtered RPLGD, various types of n-γ mixed fields are designed by irradiating different moderator assemblies with a D-D neutron source at the OKTAVIAN facility, Osaka University, Japan. The n-γ mixed fields are classified into fast neutron–, epithermal neutron–, or thermal neutron–dominated fields and a gamma-ray-only field with the specific characteristics as follows: (1) the dose ratios of gamma ray to neutron are 1.0% to 977.0% for the fast neutron–dominated field, 5.0% to 921.1% for the epithermal neutron–dominated field, 5.0% to 921.1% for the thermal neutron–dominated field, and 11880.6% for the gamma-ray-only field; (2) the proportions of fast, epithermal, and thermal neutron doses to total neutron dose are 98.4% to 100.0% for the fast neutron–dominated field, 74.0% to 85.4% for the epithermal neutron–dominated field, and 90.1% to 90.8% for the thermal neutron–dominated field, respectively; and (3) the maximum gamma-ray energy is up to 12 MeV.

Lumped Parameter Analysis of Autogenous Propellant Pressurization System for Nuclear Thermal Rocket

This work proposes a new propellant management configuration for an ammonia-fueled nuclear thermal propulsion system. The suggested configuration maximizes the advantage deriving from the autogenous pressurization of ammonia by exploiting the thermal power lost by the nuclear reactor toward the vacuum space due to leaking radiation. In this layout, a tank containing ammonia in saturated conditions is placed near the nuclear reactor and receives an input thermal power proportional to the dose of gamma rays and neutrons absorbed by the tank walls and the ammonia itself. Such a thermal power accelerates the vaporization process of the saturated ammonia, thus increasing the pressure in the tank. A pressure regulator valve exploits this overpressure to pressurize the ammonia propellant contained in a run tank to the level required by the mission by connecting the two ammonia volumes. The pressure achieved inside the run tank pushes the propellant with an adequate mass flow rate inside the nuclear reactor. The developed lumped parameter analysis shows how this propellant management system can provide a constant mass flow to the nuclear reactor without using a turbopump assembly. Moreover, it is shown how the proposed concept allows for a reduction in the radiation shield mass.

Effects of acute gamma irradiation on the morphology of Curcuma alismatifolia ‘Siam Shadow’ and C. alismatifolia ‘Siam Scarlet’

Curcuma alismatifolia (Pathumma in Thailand), also known as Siam Tulip, is an economically valuable cut flower in Thailand and is continuously bred to enhance its captivating array of colors. This study aimed to investigate the effects of acute gamma irradiation on 2 cultivars of C. alismatifolia ‘Siam Shadow’ and C. alismatifolia ‘Siam Scarlet’ for in vitro propagation and determination of the lethal dose 50 (LD50). The irradiation was conducted at doses of 0, 20, 30, 40 and 80 Gy using young shoots tissue culture. The results of the experiment revealed that the LD50 for ‘Siam Shadow’ could not be determined while ‘Siam Scarlet’ was 29.06 Gy. ‘Siam Shadow’ exhibited chimera leaf formation when exposed to a gamma irradiated dose of 40 Gy, while ‘Siam Scarlet’ exhibited chimera leaf formation when gamma irradiated at doses of 20 Gy in vitro. After planting in a greenhouse, ‘Siam Shadow’ was irradiated with 30 Gy of gamma irradiated, had reduced bract numbers and the bracts became smaller. Conversely, ‘Siam Scarlet’ irradiated with 20 Gy of gamma irradiated, produced smaller inflorescences with only 2 bracts, while irradiation with 30 Gy resulted in 2 lobes and spotted leaves at the edges of the leaves. The results indicated that both the C. alismatifolia cultivars and gamma irradiation rates had a significant influence on survival rate, number of shoots, plant height, chlorophyll mutants and morphology. As the outcome, it was determined that gamma irradiation with optimum doses of gamma rays could induce new characteristics in C. alismatifolia.

Estimation of gamma radiation effects on the polypropylene (PP) films at various doses

Medical polypropylene (PP) is exposed to ionizing radiation during the sterilization process before its use for medical purposes. Herein, the raw and manufactured PP were prepared as polymeric films with the same specifications. Then, raw and manufactured PP were irradiated by different doses of gamma rays in the air to discover the gamma radiation effects on the prepared films. The gamma doses were 25, 50, 75, 100, and 200 kGy. The irradiated raw and manufactured PP were characterized by different analytical techniques such as Electron Spin Resonance Spectrometer (ESR), Fourier Transform Infrared Spectroscopy (FTIR), X-ray diffraction (XRD), Thermogravimetric Analysis (TGA), Differential Scanning Calorimetry (DSC), Scanning Electron Microscopy (SEM), Energy Dispersive X-ray (EDX), and mechanical properties. The FTIR study indicated the presence of a new band at a low gamma dose for both cases. The crystallinity percentages of both raw and manufactured PP gradually reduced when the gamma doses increased. The thermal stability of films decreased by increasing the gamma doses. Raising the gamma dosages resulted in a decrease in the mechanical characteristics of raw PP and manufactured PP such as elongation @ break, elastic modulus, and tensile strength.

An efficient and easy-to-use protocol for induction of haploids in cucumber through parthenogenic embryo development

BackgroundCucumber (Cucumis sativus L.) is a model crop to study cell biology, including the development of haploids and doubled haploids in vegetable crops. In plant breeding, haploid and doubled haploids are valuable tools for developing pure homozygous inbred lines and accelerating genetic progress by reducing the time required for breeding cycles. Besides, the haploids are also valuable in genomic studies. We are reporting the induction of haploids in cucumber involving gynoecious and parthenocarpic genotypes for the first time. This study aimed to assess the efficient induction of haploids through pollination with gamma-irradiated pollen in cucumber. The effect of gamma irradiation dose on pollen viability and germination, fruit setting percentage, seed development, and haploid embryo development in cucumber hybrid genotypes were studied in detail. The goal was to utilize this information to produce haploid plants for genomics and transformation works in this model vegetable crop.ResultsPollination was done on six cucumber genotypes using varying doses of gamma rays (100, 200, 300, 400, and 500 Gy). Genotypes, doses of irradiation, and embryo developmental stage influenced the successful generation of in-vitro haploid plants. The optimal timeframe for embryo rescue was found to be 25 to 30 days after pollination. Haploid embryos were effectively induced using irradiated pollen at 400 to 500 Gy doses. Parthenogenetic plantlets were analyzed, and their ploidy level was confirmed through stomatal physiology, cytology (mitosis), and flow cytometry methods.ConclusionThrough parthenogenic embryo development, it is possible to induce a large number of haploids in cucumber. This technique’s power lies in its ability to streamline the breeding process, enhance genetic gain, and produce superior cultivars that contribute to sustainable agriculture and food security.

Gamma radiation induced tailoring the structural, optical, surface and mechanical properties of UHMWPE

The present investigation examined how the resultant gamma radiation affected the ultra-high molecular weight polyethylene's (UHMWPE) mechanical, optical, surface, and structural characteristics. Different gamma doses of 75, 150, 250, and 350 kGy were applied to the UHMWPE samples. The study of physical and chemical qualities has involved a variety of spectroscopy techniques, including Fourier Transform Infrared spectroscopy, X-ray diffraction, mechanical property changes, and biocompatibility properties. New bands are formed, as indicated by FT-IR analysis, and this process is linked to the oxidation of irradiation polymer chains and the production of carbon dioxide. The crystallinity of irradiated samples increases as the gamma radiation increases, according to XRD patterns. The analyzed optical results exhibit improvements in the optical characteristics of the irradiated samples. The absorbance spectra of the irradiated samples showed a shift toward the high of wavelength values in the absorption edge as compared to the pristine sample. On the other hand, the optical absorption edge has an increasing tendency as the dose of gamma-ray radiation is increased. As the gamma-ray dose increases, the absorption edge moves toward the longer wavelength. The measurements of the contact angle indicate that the surface free energy rises with increasing gamma irradiation. It was detailed how the mechanical properties of the irradiated UHMWPE samples were measured. The mechanical measurements indicate that the mechanical properties are dose-dependent to some extent. Furthermore, as gamma doses rise, so does the hardness of irradiated UHMWPE.

Application of 28.1 kDa Alginate Oligosaccharide Improves the Yield and Quality of Grain in Rice

AbstractWe conducted a phase‐wise study to evaluate the efficacy of the gamma ray‐produced oligosaccharides of alginate and chitosan in enhancing the yield in rice. Initially, we irradiated the dry powder of alginate and chitosan with 200–500 kGy dose of gamma ray to produce their oligosaccharides. Subsequently, we assessed efficiency of the aqueous solution (50–400 ppm) of these oligosaccharides to stimulate the growth in rice seedling. The elicitors which stimulated the seedling growth were later tested in the field for their ability to enhance the growth and yield in rice under six different treatment regimens. In the next two seasons we evaluated the elicitor and treatment regimen, which enhanced the yield and yield contributing factors, at a larger scale. The observations suggest that 200 ppm of alginate oligosaccharide (28.1 kDa) produced by 500 kGy of gamma ray enhances the yield in rice by 13% and improves the seed quality when sprayed during seedling, pre‐flowering and grain‐filling stages. Such treatment improves the overall growth and development of the plant, which probably enhances the yield and grain quality of the produce.

Preliminary ESR dating results of fault barite shed new insights into the retrospective history of bedrock fault activities in basaltic regions

The chronology of fault activity in bedrock is critical to constraining and understanding periods of active faulting, assessing seismic hazards, and mitigating the effects of earthquakes. However, because of the lack of suitable materials for dating, the temporal reconstruction of faulting in bedrock remains highly challenging for geologists. In the present study, we determine for the first time the electron spin resonance (ESR) ages of fault barite (BaSO4), which is produced by episodes of intense faulting on basalt bedrock fault surfaces. Three barite samples were obtained from a basalt fault section (27°5′23″N, 100°25′45″E, 1.8 km above sea level) of the Lijiang–Xiaojinhe Fault (LXF), southeastern Tibetan Plateau, for ESR measurements. Similar to marine barite, the ESR spectrum of fault barite shows an electron-type center with g = 2.0037, 2.0034, and 2.0028 attributed to SO3−. The signal intensity systematically increased with increasing gamma-ray dose. Dose rates were calculated using a model based on the location and burial depth of the barite samples, as well as their surrounding bedrock. The three barite samples yield ESR ages of 131 ± 26, 503 ± 61, and 1416 ± 246 ka, respectively, which indicate that the LXF was active during the Early and Middle Pleistocene. The three ESR ages for fault barite from basalt extend the time range of activity of the LXF compared with previous carbonate ESR and radiocarbon dating results. Consequently, we propose that ESR dating of barite is valuable for reconstructing the history of bedrock fault activity. However, given that this investigation represents a preliminary application of the fault-barite ESR method, further study is needed to confirm its usefulness and the accuracy and precision of dating results.

Effective rare-earth dielectric addition and gamma ray irradiation for achieving highly efficient PDMS triboelectric nanogenerator

This research aims to develop the flexible triboelectric nanogenerator (TENG) using PDMS polymer as the main tribo-material and composite with dielectric rare earth oxide, lanthanum chromite compound; LaCrO3, to enhance generated charge density, before add-on its higher electrical output with gamma ray irradiation. Upon study the effect of different amounts of the loaded LaCrO3 and various doses of gamma ray, the optimum condition can be obtained. The PDMS/LaCrO3 at 5 wt% can reach open-circuit voltage (VOC) and shot-circuit current (ISC) at 89 V and 448 μA. The impressive results of output further appear by additional irradiated gamma radiation. At 150 kGy dose of Irradiated gamma ray, VOC and ISC can jump to 161 V and 963 μA. These output signals, especially ISC, can be ∼34 times higher than that of the pristine PDMS. Scientific discussion regarding characterization, operating mechanism, dielectric properties and electrical output is provided. The practical application of being a small power source is also developed. Therefore, this research can show another useful application of gamma ray in the field of materials design for energy harvesting devices. The knowledge provided in this research can also serve as potential guidance in the field of specific TENG utilization.

Effect of Gamma Irradiation and Ems on Germination and Survival of Okra (Abelmoschus esculentus L.) cv Arka Nikita

The present investigation was devised to observe different doses of chemical and physical mutagen on the germination and survival percentage of okra variety Arka Nikita. Seeds of okra variety Arka Nikita were treated with different doses of gamma rays and EMS. The experiment was laid out in Randomized Complete Block Design (RCBD) with thirteen treatments and three replications. It was clearly observed that germination and survival percentage decreased with increase in doses of gamma rays and EMS. Results revealed that among different treatments, treatment T1 (Control) recorded maximum germination (85) and survival per cent (98.82) and observed dose-dependent reduction in biological factors such as germination and survival, the LD50 values for gamma rays and EMS were 0.4% and 60 kR, respectively.

Influence of gamma-irradiation on the physical properties of epoxy/polyaniline composites and application as gamma dosimeter

Abstract The epoxy/pani samples doped with a specified weight ratio of polyaniline pani ware prepare by casting method. Using different doses of gamma rays (0, 2, and 4 kGy) were used to irradiated the prepared samples. Irradiated and non-irradiated samples were imaged using a FE-scanning electron microscope and were found to have regular morphology, and irradiation had obvious effect on this morphology at 4 kGy. When studying the crystal structure of the samples, it was found the samples have a polycrystalline structure, and this structure tends to improve after irradiation, this was verified using X-ray diffraction. Likewise, D.C electrical conductivity increased with increasing gamma radiation doses. Also study the effect of irradiation with gamma rays on optical properties and demonstrate the clear effect of these rays on optical properties. It was also found that the optical energy gap with (indirect allowed transition) was decreases after the irradiation process. Together, these results indicate the possibility of using these samples in the manufacture of gamma dosimeters.

Improvement of antibacterial activity of AgNPs@PVA-PVP ternary nanocomposite films followed by gamma-ray irradiation treatment for biomedical applications

Our study investigates the influence of several doses of gamma rays on the antibacterial behavior of nanocomposite of silver nanoparticles (AgNPs) doped in a blend of poly (vinyl alcohol) (PVA)-Polyvinyl Pyrrolidone (PVP). AgNPs@PVA-PVP nanocomposite films have been fabricated by laser ablation method, and then the synthesized films were subjected to various gamma ray’s doses. X-ray diffraction (XRD) data shows a diffraction peak at 2θ = 38° assigned to the existence of AgNPs. Ultraviolet–visible (UV-Vis) results confirm the characteristic peak of silver nanoparticles at 425 nm. The cell viability and antibacterial behavior results confirmed the enhancement in the performance of AgNPs@PVA-PVP composite after irradiated to gamma rays. These values of cell viability have been raised by increasing the dose of gamma rays to 94.5±6.5 % for dose at 70 kGy gamma rays. The values of the inhibition zone of microorganisms were enhanced by raising the doses of gamma rays to 19.5±0.5 and 21.3±0.6 against E. coli and S. aureus respectively specifically for nanocomposite with gamma dose 70 kGy. Thus, the improved antibacterial activity of AgNPs@PVA-PVP nanocomposite could be used in biomedical applications.

Dose mapping of a 252Cf based non-destructive on-line elemental analysis device using Monte Carlo simulation and verification with experimental results

Environmental dose values are critical for human health in non-destructive analysis systems. The International Commission on Radiological Protection (ICRP) has defined specific limitations for permissible dose values. This study assesses the dose distribution of a prototype analysis device utilizing Californium-252 (252Cf) radioactive material through both Monte Carlo simulations and laboratory experiments. Conducted at the Istanbul Technical University (ITU) Energy Institute, the experimental investigation measured gamma-ray and neutron dose values surrounding the device. The objective was to compare dose maps generated by the Monte Carlo-based GEANT4 code with experimental data. Ten dose maps were created, and fundamental statistical analyses were performed. Results indicate that the dose values on the operator’s working surface of the prototype device are within ICRP limits, not exceeding 1 millisievert (mSv) annually, with an effective dose rate of 0.949±0.052 mSv per year. These findings underscore the device’s potential for safe and effective use in radiation safety and environmental dose assessment.

Selection of the Optimal Concentration of Nitro Blue Tetrazolium Dye in Polyvinyl Alcohol Film for Diagnostic Radiology

Ensuring the limited exposure of both patients and medical professionals to radiation during examinations is paramount. One effective approach is the utilization of a film dosimeter that is not only efficient but also easy to carry. In this research, we employed polyvinyl alcohol/nitro blue tetrazolium (PVA/NBT) with varying concentrations of NBT dye (ranging from 0.015 to 0.3 g) to identify the most optimal concentration. These films were subjected to low doses of gamma rays (8, 25, 55 and 96 mGy) emitted from 3 Cs-137 sources. XRF analysis confirmed the effectiveness of the preparation method used, and the NBT salt exhibited excellent solubility (R2 = 0.93). The films exhibited an increasing yellow hue as the concentration of NBT dye rose. Following irradiation, they took on a yellowish-brown tint, intensifying with higher gamma doses. PVA/NBT films, when stored in the dark, demonstrated good stability for 30 days post-irradiation. Analysis using ImageJ software unveiled that the relative density of the red color heightened proportionally with the concentration of NBT dye. XRD patterns showcased the clarity of structural rearrangements occurring after irradiation with high NBT concentrations. Two distinct peaks were registered at 2θ = 20.12 and 40.94 °, which shifted to 2θ = 19.74 and 41.30 ° post-gamma irradiation. The CIELab system study and K/S color strength indicated that increasing the NBT dye concentration led to a linear rise in color strength with escalating low gamma doses. Through a comprehensive assessment, it is concluded that PVA/NBT film can be effectively employed as a dosimeter for low gamma doses in diagnostic radiology. HIGHLIGHTS Nine different concentrations of NBT dye were used to prepare PVA/NBT films. The standard dose scale in diagnostic radiology (mGy) was applied in this work. CIELab system parameters showed a linear increase with increasing applied dose. XRD pattern recorded a shifted peak after irradiation from 2θ = 20.12 to 19.74 °. The dose-response was affected by increasing the NBT dye to a certain concentration. GRAPHICAL ABSTRACT

Agro-morphological evaluation of gamma ray-induced mutant populations and isolation of harder grain mutants in wheat (Triticum aestivum L.)

Abstract Gamma ray-induced mutations have been widely used to improve existing crop germplasm and create novel genetic variation. In the current study, a multi-year experiment was carried out to induce and isolate mutants with desirable agro-morphological traits and improved grain hardness through evaluation of induced mutant populations generated in soft-textured wheat variety HPW 89 irradiated with gamma ray dose of 250, 300 and 350 Gy. Mutagen sensitivity studies revealed a higher frequency of biological damage and seedling mortality for doses beyond 300 Gy in the M1 generation. However, the mutagenic treatments in the M2–3 populations significantly altered the magnitude of the biometrical traits. Results from the variability and association studies among traits showed that biological yield per plant, 1000-grain weight, spike length, grains per spike and plant height may be prioritized for higher genetic gain and could be used as selection criteria parameters. Multivariate analysis indicated induction of heterogeneity among mutant populations. Overall, 250–300 Gy doses were found ideal for a successful wheat mutation programme and 293 agro-morphologically superior wheat mutants were identified, out of which 108 had semi-hard grain texture based on single kernel characterization system. Among these, nine mutants were found to have the highest grain hardness index due to induced changes in one or both puroindoline genes. Hence, these mutants identified for several traits along with harder grain texture will serve as important genetic resource in future wheat-breeding programmes.

DEGRADATION KINETICS OF TEXTILE AZO DYE REACTIVE ORANGE-16 BY GAMMA IRRADIATION

Gamma radiation have become attention since their high potential for degrading compounds, especially organic pollutants. In this research, gamma radiation was studied for degrading the Reactive Orange-16 (RO-16) dye, a toxic and carcinogenic pollutant. The radiolytic degradation process was studied in a batch reactor with a gamma-ray dose rate of 2.930 kGy/h. The effect of experimental variable such as initial peroxide concentration, initial pH, initial dye concentration, and addition of inorganic anion were studied. The highest degradation rates were achieved at a peroxide concentration ranging from 2 to 4 mM. In contrast, the higher peroxide concentration indicated the slower degradation process caused by the scavenging effect of the peroxide. Degradation of 88% RO-16 dye with 0.1 mM initial concentration, was achieved at 2.0 kGy irradiation dose and 97.4% degradation in the presence of 4 mM peroxide. The dose constant (d) for those degradation processes was 1.0657 kGy-1 and 1.8420 kGy-1 respectively. The degradation was more efficient in acid pH. The degradation process increased with lower initial dye concentrations. The degradation of RO-16 dye by gamma-ray was inhibited by the presence of inorganic anions in the following sequence: NO3-→ CO32− → HCO3− → CH3COO-→ Cl-.

On the response of the CR-39 NTD to low doses of gamma rays using optical and photoluminescence spectroscopy

In this work, the response of the CR-39 nuclear track detector (NTD) exposed to different low doses of gamma rays was investigated using UV–Vis and photoluminescence spectroscopy. Five NTDs of CR-39 were irradiated with low gamma-ray doses ranging from 10 to 120 kGy using a60Co source. The dose of gamma rays correlates with red shift in the absorption spectra of a gamma-irradiated CR-39 detector. As the gamma dose increases, the indirect and direct energy band gaps, as well as Urbach energy, decrease gradually. However, the decrease in the indirect optical band gap is greater than the decrease in the direct band gap. The observed spectra of the CR-39 detector after being irradiated with different doses of γ-rays showed an acceptable variation in photoluminescence (PL) emission spectra generated by a well-defined excitation wavelength of 290 nm. Starting at 45 kGy dose, the integrated area of the photoluminescence peak increases and tends to saturate, whereas the photoluminescence peak height is linearly correlated with the gamma dose with high sensitivity, which is 53.1 ± 6.3 CPS. kGy−1. According to the current findings, photoluminescence (PL) spectroscopy has a greater sensitivity than UV–Vis spectroscopy for measuring the response of the CR-39 detector to gamma rays in the dose range of 10–120 kGy. The results reflected a potential possibility of using the CR-39 detector in dosimetric applications of low gamma ray doses through the high resolution achieved by photoluminescence (PL) and UV–Vis spectroscopy.

Exploring the effects of the alkaline earth metal cations on the electronic structure, photostability and radiation hardness of lead halide perovskites

The growing interest to the application of perovskite solar cells (PSC) in aerospace requires great attention to the design of new absorber materials with enhanced photostability and radiation hardness. We addressed this challenge through the B-site engineering by partial replacing of Pb2+ in the complex halides with Ca2+, Sr2+, and Ba2+. Change in the material electronic properties suggests the incorporation of the substituent cations in the perovskite lattice. However, when the loading of alkaline earth halides is high, they tend to segregate to the film surface and grain boundaries. The modification of MAPbI3 and Cs0.12FA0.88PbI3 by replacing a 1% of Pb2+ with alkaline earth metal cations resulted in improvements in the photostability and radiation hardness under exposure to gamma rays and electrons beam. Depending on the material formulation, it was possible to mitigate the photochemical and radiation-induced Pb0 formation and the univalent cation phase segregation. The best of the designed perovskite absorbers could successfully tolerate high doses of gamma rays (5.5 MGy) and electron fluences (3 × 1016 e/cm2), thus outperforming significantly the non-modified material. These findings feature the incorporation of alkaline earth metal cations as a promising approach for the development of PSC with enhanced radiation hardness for aerospace applications.

Implementation of optically simulated luminescent dosimeter for quality control of gamma ray dose of an accelerator-based neutron source.

Neutron beams utilized for performing BNCT are composed of a mixture of neutrons and gamma rays. Although much of the dose delivered to the cancer cells comes from the high LET particles produced by the boron neutron capture reaction, the dose delivered to the healthy tissues from unwanted gamma rays cannot be ignored. With the increase in the number of accelerators for BNCT, a detector system that is capable of measuring gamma ray dose in a mixed neutron/gamma irradiation field is crucial. Currently, BeO TLDs encased in quartz glass are used to measure gamma ray dose in a BNCT irradiation field. However, this type of TLD is no longer commercially available. A replacement dosimetry system is required to perform the recommended ongoing quality assurance of gamma ray measurement for a clinical BNCT system. The purpose of this study is to evaluate the characteristics of a BeO OSLD detector system under a mixed neutron and gamma ray irradiation field and to assess the suitability of the system for routine quality assurance measurements of an accelerator-based BNCT facility. The myOSLD system by RadPro International GmbH was evaluated using the accelerator-based neutron source designed for clinical BNCT (NeuCure BNCT system). The readout constancy, linearity, dose rate effect, and fading effect of the OSLD were evaluated. Free-in-air and water phantom measurements were performed and compared with the TLD results and Monte Carlo simulation results. The PHITS Monte Carlo code was used for this study. The readout constancy was found to be stable over a month-long period and similar to the TLD results. The OSLD readout signal was found to be linear, with a high coefficient of determination (R2≥0.999) up to a proton charge of 3.6C. There was no significant signal fading or dose rate dependency. The central axis depth dose and off-axis dose profile measurements agreed with both the TLD and Monte Carlo simulation results, within one standard deviation. The myOSLD system was characterized using an accelerator system designed for clinical BNCT. The experimental measurements confirmed the OSLD achieved similar, if not superior to, the currently utilized dosimetry system for routine QA of an accelerator-based BNCT system. The OSLD system would be a suitable replacement for the current TLD system for performing routine QA of gamma ray dose measurement in a BNCT irradiation field.