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Concrete is the favored construction material, with more than 7 billion cubic meters manufactured annually. Aggregates constitute the crucial component of its structure and quality, responsible for its exceptional characteristic features. The characteristics of aggregates determine the mechanical durability and radiation performance of concrete. In this investigation, fabricated concrete specimens were generated by replacing sand and aggregate sizes with pyrophyllite in 10%–20%–30%–100% proportions. The study investigated the mechanical properties of concrete specimens using both pressure and ultrasound methods, as well as their durability under freeze–thaw and high-temperature (200°C–1,000°C) conditions. In addition, the microstructure and radiation permeability properties were examined over a 7–28–90-day period. Notably, the use of pyrophyllite sand and aggregate significantly increased the compressive strength of the specimens by 21%–63% when compared to the reference concrete after 7–28–90 days, while also reducing mass loss by up to 4.6% during freeze–thaw cycles. After subjecting the specimens to high temperatures, it was discovered that those with an air-cooling regime achieved a compressive value 45% higher than the reference concrete. Microstructure images revealed the formation of C─ S─ H, CH, and portlandite hydration products over 90 days, supporting the observed compressive strength values. The study also has an effective linear attenuation coefficient (LAC) for radiation-shielding properties. According to some radiation-shielding parameters calculated through LAC values, it was revealed that these concrete samples were suitable shielding materials. Pyrophyllite-reinforced specimens have demonstrated potential for high-strength concrete production, suitability for use in high-temperature environments, and effectiveness as shielding in areas with radiation sources. [ABSTRACT FROM AUTHOR]

The main objective of this study is to measure the levels of radioactivity in certain construction material samples by quantifying the amounts of natural radionuclides (238U, 232Th, 40K) and 137Sc using gamma-ray spectroscopy with a High Purity Germanium (HPGe) detector. The selected samples were collected and examined to ascertain the mean quantities of radionuclides present. Subsequently, these findings were juxtaposed with global benchmarks for additional examination. The efficiency results unveiled a spectrum of concentrations for different radionuclides, encompassing 238U with a concentration range of (2.53 - 8.2 Bq/kg) and an average concentration of (4.93 Bq/kg). Similarly, the concentration of 232Th ranged from (0.655 - 3.45 Bq/kg), with an average concentration of (1.74 Bq/kg). The radionuclide 40k exhibited a concentration range of (3.5 -1500 Bq/kg), with an average value of (386.4 Bq/kg). Furthermore, 137Sc displayed a concentration range of (0.51-0.22 Bq/kg) with an average concentration of (0.53 Bq/kg). The radium equivalent concentration was determined to be (40.45 Bq/kg), whereas the absorbed dosage was measured at (18.67 nGy/h). The external hazard index (Hout) was measured to equal (0.11 mSv/y), whereas the internal hazard index (Hin) was determined to be (0.17 mSv/y). Furthermore, the annual equivalent effective dose (AEDEout) was calculated to be (0.09 mSv/year). The annual dosage of (AEDEin) was determined to be (0.02 mSv/year). The gamma radiation index, denoted as Iγ, was determined to be (0.28 Bq/kg). The study results imply that the amounts of radionuclides fall within the defined normal limits worldwide, indicating that the natural radioactivity levels are within the internationally acceptable range. Quantification of both natural and artificial radioactivity in specific building materials employed in constructing dwellings inside Salah Al-Din Governorate. A selection of seven distinct models was made. (Plaster, Bork, and Dust). The concentration of gamma-ray-emitting radionuclides in both the uranium-radium and thorium series, as well as 40K and 137Sc, was measured using a high-purity germanium (HpGe) detector. Subsequently, the spectrum underwent analysis for 3600 seconds. The concentrations of the radionuclides being investigated were determined to be as follows: The mean concentrations of 238U range from (2.53 - 8.2 Bq/kg), while for 232Th the range from (0.65 to 3.45 Bq/kg). The concentrations of potassium 40K range from (3.5 to 1500 Bq/kg), and for 137 Sc the range from 0.51 to 0.22 Bq/kg. [ABSTRACT FROM AUTHOR]

The radiation shielding properties of different samples of borate-tellurite glass were investigated using WO3 modifiers. Geometric optimization and modification of pristine borate-tellurite with WO3 were carried out based on density functional theory calculations using plane wave basis sets and pseudo-potentials. It was observed that the changes in the physical properties of the white box testing glass (WBTG) systems were determined by WO3 content. Analysis of the linear attenuation coefficient of the sampled glasses, which yielded a value of 7.43 cm for WBTG1 at 20 keV, indicated that WBTG1 was able to stop gamma radiation from Cs-137 and Th-237 sources. Both the µ and µm values were zero above 0.15 MeV, indicating that the WBTG composite was only able to attenuate low-energy photons such as gamma rays. It was found that the characteristic behavior of the WBTG was generally determined primarily by oxygen content, which is in good agreement with theoretical and experimental data. [ABSTRACT FROM AUTHOR]

Abstract Concrete has been widely utilized as a radiation shielding material due to its properties and structural integrity. This study aims to evaluate the efficiency of ordinary concrete versus barite concrete as radiation shielding materials, focusing on the physical aspects and changes in crystal size lattice parameters after neutron irradiation. Specifically, the research investigates the shielding effectiveness of these materials across different grades (M15, M25, M35, and M45) against gamma-ray sources Cobalt-60 and Caesium-137. The methodology involves measuring the linear attenuation coefficient (μ), half value layer (HVL), tenth value layer (TVL), and mean free path (MFP). Additionally, X-ray diffraction (XRD) was employed to assess crystallite size and lattice parameter changes post-irradiation for neutron irradiation. Results indicate that incorporating barite as an aggregate significantly enhances the density and crystallite macroscopic properties of the concrete. Irradiation with Cobalt-60 and Cesium 137 revealed that ordinary concrete has a lower linear attenuation (μ) ranging from 0.172 to 0.195 cm−1, with consistent mass attenuation across all grades at 0.81 cm2/g. XRD analysis demonstrated a rightward shift in the SiO₂ and BaSO₄ peaks post-irradiation, signifying crystalline expansion. In terms of lattice parameters, the d-value showed a notable decrease of 0.10 after 48 h of irradiation in grade 25, while the most significant increase of 0.02 occurred after 24 h of irradiation in grades 15 and 45. In conclusion, barite concrete proves to be more effective for radiation shielding in nuclear facilities, whereas ordinary concrete is suitable for medical shielding, or facilities exposed to lower radiation doses.

This study focuses on the development and evaluation of a novel cement-free gamma-ray-resistant ultrahigh-performance concrete (UHPC), known as UHPC-CAS. UHPC-CAS is composed of calcium oxide–activated slag, iron and barite powders, and steel fibers, making it a type of ultrahigh-performance geopolymer concrete (UHPGC). In this study, the effects of replacing silica sand with varying percentages of iron and barite powders on the mechanical and radiation properties of UHPC-CAS were investigated. The optimal replacement ratio of iron powder was found to be 50%, resulting in the highest compressive, tensile, and bending strengths among all mixtures without fibers. Furthermore, the UHPC-CAS samples reinforced with steel fibers and containing barite powder exhibited a more pronounced softening zone than those containing iron powder. With 100% iron powder and 3% steel fibers, UHPC-CAS achieved superior resistance to gamma rays, as evidenced by the highest attenuation coefficient of 0.234 cm and the lowest half-value layer of 2.96 cm. This research demonstrates the potential for developing sustainable cement-free UHPC for use in nuclear facilities and other applications requiring high radiation shielding. [ABSTRACT FROM AUTHOR]

Abstract Since the beginning of research into radiation and protection against it, the importance of searching for proper materials against radiation hazards has been recognized. Gamma radiation protection materials usually deal with heavy elements with high prices, which are hard to maintain. Polyurethane-based (PU) materials are popular in sound and thermal insulation due to, their low-weight properties and, most importantly, fast and convenient construction ingredients. PU foams (PUF) can be used as radiation shield and noise and heat resistance due to their approachability, light-weight, high resistance, and comfortable construction. This study involved simulation and an experiment to construct and investigate the properties of Polyurethane material doped with lead oxide as a gamma shield. The shield was considered in several weight fractions of lead, yielding several samples. The MCNPX 2.6 Monte Carlo code has been utilized for simulation procedure, and 137Cs was employed as the gamma source in both simulation and experiment. The results offer a promising response against the gamma radiation and are suitable for attenuating gamma rays.

For the development of the remote elemental analysis method in a radiation environment based on the laser-induced breakdown spectroscopy (LIBS), the radiation effects on the laser oscillation properties of the single crystal (SC) Nd:YAG microchip laser (MCL) were investigated and compared with those of ceramic Nd:YAG MCL. The laser oscillation properties were measured under gamma ray irradiation as a function of dose rate. The effects on the SC MCL properties were very small compared to those on the ceramics, indicating minimal radiation effects on the LIBS signal when using SC MCL. Pulse energy and oscillating build-up time (BUT) were measured for cumulative dose exceeding 1400 kGy. The pulse energy remained stable under irradiation. The BUT also remained stable, demonstrating negligible optical loss accumulation that could affect laser properties even at the demonstrated cumulative dose. The results indicate that the effects of dose rate and cumulative dose on SC MCL laser properties are minimal. The SC MCL was then integrated into the LIBS system, and the gadolinium signal was successfully measured at a dose rate of 5 kGy/hr. These findings highlight the radiation tolerance of SC MCL for remote LIBS applications in harsh radiation environments. [ABSTRACT FROM AUTHOR]

Silicon photomultipliers (SiPMs) are solid-state single-photon-sensitive detectors that show excellent performance in a wide range of applications. In FBK (Trento, Italy), we developed a position-sensitive SiPM technology, called "linearly graded" (LG-SiPM), which is based on an avalanche-current weighted-partitioning approach. It shows position reconstruction resolution below 250 μm on an 8 × 8 mm2 device area with four readout channels and minimal distortions. A recent development in terms of LG-SIPM is a larger chip version (10 × 10 mm2) based on FBK NUV-HD technology (near-ultraviolet sensitive), with a peak photon detection efficiency at 420 nm. Such a large-area detector with position sensitivity is very interesting in applications like MR-compatible PET, high-energy physics experiments, and readout of time-projection chambers, gamma and beta cameras, or scintillating fibers, with a reduced number of channels. These SiPMs were characterized in terms of noise, photon detection efficiency, and position resolution. We also developed tiles of 2 × 2 and 3 × 3 LG-SiPMs, reaching very large sensitive areas of 20 × 20 mm2 and 30 × 30 mm2. We implemented a "smart-channel" configuration, which allowed us to have just six output channels for the 2 × 2 elements and eight channels for the 3 × 3 element tiles, preserving a position resolution below 0.5 mm. These kinds of detectors provide a great advantage in compact and low-power applications by maintaining position sensitivity over large areas with a small number of channels. [ABSTRACT FROM AUTHOR]

Since the beginning of research into radiation and protection against it, the importance of searching for proper materials against radiation hazards has been recognized. Gamma radiation protection materials usually deal with heavy elements with high prices, which are hard to maintain. Polyurethane-based (PU) materials are popular in sound and thermal insulation due to, their low-weight properties and, most importantly, fast and convenient construction ingredients. PU foams (PUF) can be used as radiation shield and noise and heat resistance due to their approachability, light-weight, high resistance, and comfortable construction. This study involved simulation and an experiment to construct and investigate the properties of Polyurethane material doped with lead oxide as a gamma shield. The shield was considered in several weight fractions of lead, yielding several samples. The MCNPX 2.6 Monte Carlo code has been utilized for simulation procedure, and 137Cs was employed as the gamma source in both simulation and experiment. The results offer a promising response against the gamma radiation and are suitable for attenuating gamma rays. [ABSTRACT FROM AUTHOR]

The increasing application of nuclear technology in medical fields has amplified the demand for radiation shielding materials. Traditional large-volume concrete cannot simultaneously exhibit excellent neutron and gamma-ray shielding capabilities while ensuring superior mechanical properties. This study tailored a novel lead fiber-reinforced high-performance concrete (LFRHPC) with lead fibers and magnetite aggregates, focusing on radiation attenuation. The effect of lead fibers on the mechanical performance, microstructure and radiation attenuation characteristics for LFRHPC was comprehensively evaluated. The results indicate a significant improvement in the mechanical performance of LFRHPC compared to traditional radiation shielding concrete (RSC), due to the scientific skeleton design. Additionally, the pore structure in LFRHPC is refined by incorporating lead fibers. Moreover, the interfacial transition zone (ITZ) between the cementitious matrix and magnetite is improved because of the very low water-to-binder ratio. To assess the radiation attenuation ability of LFRHPC, both direct measurements and simulation models were utilized. The data reveals that the porosity of LFRHPC plays a crucial role in its shielding effectiveness against neutron and gamma radiation. Furthermore, the addition of lead fibers considerably boosts its neutron and gamma-ray shielding attenuation capabilities. In summation, LFRHPC combines excellent mechanical properties and radiation shielding capabilities, making it suitable for construction applications in medical settings. [ABSTRACT FROM AUTHOR]

The purpose of this research is assessing the significance of biological and physical seeds invigoration of different aged carrot seeds orders and study their field performance. An implementation of field experiment at station (A) College of Agricultural Engineering Sciences - University of Baghdad during fall season 2021-2022. The experimental design arranged using split plot within RCBD. As carrot seeds order considered main plots (primary P, secondary S, tertiary T) and seeds invigoration treatments sub plots (untreated seeds C0, biological B, Physical G, B+G) with three replicates (3X4X3). The interaction treatment PBG (biological+physical treated primary seeds order) reveals significance in majority of research traits such as field emergence percent, carrot total carotenoids, scavenging percent, total yield (97.67%,12.66mg.100g, 88%, 126.1 ton.ha-1 ) respectively in compare to untreated tertiary seeds order (TC0). [ABSTRACT FROM AUTHOR]

One of the most important health problems worldwide is the increase in pathogenic microorganisms resistant to a variety of antimicrobial materials. In this study, the antibacterial properties of biosynthesized Ag/AgCl Nanoparticles (Ag NPs) by Satureja hortensis leaf extract under different gamma ray doses were compared. Biosynthesis of Ag NPs was performed by leaf extract of S. hortensis grown from seeds exposed to different gamma ray doses (0, 15, 30, 60 and 90 gray). Formation of Ag NPs confirmed by UV-Visible spectroscopy and X-ray diffraction (XRD) methods.The biosynthesized nanoparticles were characterized using Dynamic Light Scattering (DLS), Field Emission Scanning Electron Microscope (FESEM) and Energy Dispersive X-ray analysis (EDAX).The functional groups of the biomolecules involved in the process were identified using Fourier Transform Infrared Spectroscopy (FTIR) and antibacterial properties of the biosynthesized Ag NPs were performed by disc diffusion method. The highest antibacterial property of the biosynthesized Ag NPs was related to 15 gray dose of gamma radiation with mean diameter of the nanoparticles about 40.02 nm in size and zone of inhibition about 13 mm in diameter against Escherichia coli and the lowest was observed in treatment 90 gray with mean diameter about 170.62 nm in size and zone of inhibition about 10 mm in diameter against the same bacteria. Biosynthesized Ag NPs using S. hortensis extract under 15 gray dose of gamma irradiation revealed the highest antibacterial properties against Bacillus subtilis and especially Escherichia coli. The high biocompatibility of these biogenic nanoparticles makes them a suitable alternative to similar materials synthesized by non-biological methods. [ABSTRACT FROM AUTHOR]

Copyright of Journal of University of Anbar for Pure Science is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

An isostatic hot-pressing technique for the fabrication of dense W samples' is presented. The samples’ microstructure and chemical content were analyzed. The most compact samples were received at 5 GPa pressure and 1500 and 2000 °C temperatures, with densities of 18.50 and 19.07 g/cm3, respectively. It has been established that high temperature exposure has a positive effect on both the microstructure and density. It is shown that as the sintering temperature increases, the porosity of the samples decreases from 32.31% to 0.94%, and their relative density increases from 67.69% to 99.06%. The crystal structure investigation revealed that all the samples contain the main body-centered cubic W phase, and the availability of the WO2 phase is observed just after the temperature of sintering increases above 1000 °C, which is confirmed by the appearance of 111 and 22-2 reflections. A study of the shielding effectiveness against gamma-radiation was carried out using the Phy-X/PSD software. A gamma-ray source of Co60 with energies of 0.8–2.5 MeV was applied for the calculations. The results were calculated for the sample with the highest density (19.07 g/cm3) and compared with the calculations for Pb. The W shielding effectiveness main parameters are determined: linear attenuation coefficient (at 0.8 MeV–1.46 cm-1), mean free path (at 2.5 MeV–1.2 cm) and half value layer (at 2.5 MeV–0.86 cm). These values turned out to be higher than for Pb, which makes shields based on W promising for use in the field of radiation protection.

Abstract This study assessed the gamma-ray shielding potential of clay, sand, gypsum and kaolin commonly used as a building material in Northwestern, Nigeria. The radiological status of the samples was first evaluated by determining the activity concentrations of 238U, 232Th and 40K using NaI (Tl) detector after which elemental composition and mass density were determined using Neutron Activation Analytical Technique. After which the mass attenuation coefficients (MAC), linear attenuation coefficients (LAC), half value layer (HVL), tenth value layer (TVL), and effective atomic number (Zeff) were determined experimentally and theoretically using standard point sources of 137Cs and 60Co photon peaks (0.662 and 1.332, 1.173) MeV and Py-MLBUF software. The activity concentrations were found to range from 51 to 59 Bq kg−1 with a mean value of 59 Bq kg−1 for 238U, 24 to 27 Bq kg−1 with a mean value of 29 Bq kg−1 for 232Th, and 219 to 247 Bq kg−1 with a mean value of 247 Bq kg−1 for 40K which were about within the world recommended values of 33, 45 and 420 Bq kg−1 respectively. The results of the elemental compositions show that Si, Al, K, Fe, and Ba in clay and sand samples have concentrations in the range of 36.83–78.48%, 1.92–26.05%, 6.33–21.96%, 2.39–19.09%, and 0.09–1.44%, respectively, while in kaolin and gypsum, results revealed that Si, Al, K, Fe, and Ca range between 0.34 and 65.52%, 1.14–35.82%, 0.00–12.12%, 0.00–5.77%, and 0.00–96.6%, respectively. However, the concentrations of other elements such as Mg, Ti, Mn, Zn, Na, and Ba varied significantly with the samples. The results showed that clay has an average density of 1.96 g/cm3, sand has 2.32 g/cm3, kaolin has 2.63 g/cm3, and gypsum has the highest density with a value of 2.66 g/cm3 compared to other samples. During the measurements, a thallium-activated sodium-iodide NaI (TI) detector was used. A narrow beam transmission geometry condition was adopted for the measurements to ensure minimal scattered radiation. Absorption and attenuation of gamma beams as a function of sample thickness against gamma energy generally exhibit an increasing gamma ray behaviour as the sample thickness increases from 1 to 3 cm. The results showed that the gypsum, kaolin, sand, and clay were capable of attenuating 63.5%, 61.5%, 58.4%, and 44.2 of gamma-ray photons of energy 0.662 MeV at 3 cm thickness %, respectively, and 40.6%, 32.9%, 30.6%, and 27.3% of gamma energy 1.332 MeV at 3 cm thickness, respectively. The results showed that MAC, LAC, and Zeff of all the samples decreased with an increase in photon energy, while those of HVL and TVL increased. The experimental results for all the gamma-ray shielding parameters were found to be in good agreement with the theoretical values obtained using Py-MLBUF. The results have shown that all the samples have similar photon attenuation behaviours; however, gypsum has the best shielding potential than kaolin and this is attributed due to its highest density value.

131I is a fission product produced in a nuclear reactor by irradiating tellurium dioxide, with a half-life of 8.02 day. The most important and widely used method for making 131I is irradiation using a nuclear reactor and post-irradiation followed by dry distillation. The advantage of the dry distillation process is that the process and the equipment are relatively simple, namely TeO2 (m.p. 750 °C), which can withstand heating during reactor irradiation. Based on TeO2 irradiation by neutron following the technique of dry distillation was explained for production of 131I on a large scale. A dry distillation followed the radioisotope production operation using the 30 MW GA Siwabessy nuclear reactor to meet national demand. TeO2 targets are 25 and 50 g irradiated for 87–100 h. The resulting 131I activity is 20.29339–368.50335GBq. According to the requirements imposed on the radionuclide purity of the preparation, the contribution of 131I training in the resulting preparation was not less than 99.9 %

This study assessed the gamma-ray shielding potential of clay, sand, gypsum and kaolin commonly used as a building material in Northwestern, Nigeria. The radiological status of the samples was first evaluated by determining the activity concentrations of 238U, 232Th and 40K using NaI (Tl) detector after which elemental composition and mass density were determined using Neutron Activation Analytical Technique. After which the mass attenuation coefficients (MAC), linear attenuation coefficients (LAC), half value layer (HVL), tenth value layer (TVL), and effective atomic number (Zeff) were determined experimentally and theoretically using standard point sources of 137Cs and 60Co photon peaks (0.662 and 1.332, 1.173) MeV and Py-MLBUF software. The activity concentrations were found to range from 51 to 59 Bq kg−1 with a mean value of 59 Bq kg−1 for 238U, 24 to 27 Bq kg−1 with a mean value of 29 Bq kg−1 for 232Th, and 219 to 247 Bq kg−1 with a mean value of 247 Bq kg−1 for 40K which were about within the world recommended values of 33, 45 and 420 Bq kg−1 respectively. The results of the elemental compositions show that Si, Al, K, Fe, and Ba in clay and sand samples have concentrations in the range of 36.83–78.48%, 1.92–26.05%, 6.33–21.96%, 2.39–19.09%, and 0.09–1.44%, respectively, while in kaolin and gypsum, results revealed that Si, Al, K, Fe, and Ca range between 0.34 and 65.52%, 1.14–35.82%, 0.00–12.12%, 0.00–5.77%, and 0.00–96.6%, respectively. However, the concentrations of other elements such as Mg, Ti, Mn, Zn, Na, and Ba varied significantly with the samples. The results showed that clay has an average density of 1.96 g/cm3, sand has 2.32 g/cm3, kaolin has 2.63 g/cm3, and gypsum has the highest density with a value of 2.66 g/cm3 compared to other samples. During the measurements, a thallium-activated sodium-iodide NaI (TI) detector was used. A narrow beam transmission geometry condition was adopted for the measurements to ensure minimal scattered radiation. Absorption and attenuation of gamma beams as a function of sample thickness against gamma energy generally exhibit an increasing gamma ray behaviour as the sample thickness increases from 1 to 3 cm. The results showed that the gypsum, kaolin, sand, and clay were capable of attenuating 63.5%, 61.5%, 58.4%, and 44.2 of gamma-ray photons of energy 0.662 MeV at 3 cm thickness %, respectively, and 40.6%, 32.9%, 30.6%, and 27.3% of gamma energy 1.332 MeV at 3 cm thickness, respectively. The results showed that MAC, LAC, and Zeff of all the samples decreased with an increase in photon energy, while those of HVL and TVL increased. The experimental results for all the gamma-ray shielding parameters were found to be in good agreement with the theoretical values obtained using Py-MLBUF. The results have shown that all the samples have similar photon attenuation behaviours; however, gypsum has the best shielding potential than kaolin and this is attributed due to its highest density value. [ABSTRACT FROM AUTHOR]

The current study aims to synthesize radiation-shielding glass materials by adding MgO in different ratios. The melt quenching technique was used to produce the MgO doped glasses. XRD examination verified the produced MgO cubic phase. Glass samples were examined for their various physical properties and gamma radiation shielding abilities. The density of obtained samples rises with MgO concentration, from 2.647 to 2.744 g cm–3. Experimental measurements of the MgO adding glasses' LAC, HVL, TVL, MFP, and MAC values were made for gamma-ray energies of 384, 1173, and 1333 keV. For gamma rays with energy of 384, 1173, and 1333 keV, existing glasses displayed a decreasing behavior in the half value layer with an increase in MgO additive, whereas it caused an increase in behavior in the linear absorption coefficient and mass attenuation coefficient values. These findings suggest that current glasses hold promise for use in radiation shielding. [ABSTRACT FROM AUTHOR]

The impact of the insertion of Pb2+ ions into the Li2O–BaO–B2O3 based glass matrix has been investigated. The Archimedes' method was used to determine the density (ρ) and, as a result, the molar volume (Vm) of the samples. The ρ of the glasses increased from 2.917 to 5.003 (g/cm3), and the Vm increased from 24.155 to 27.074 (cm3/mol). The optical band gap of the samples was determined based on their UV–visible spectra. The structural study of the present glasses has been carried out by XRD patterns and FTIR spectra analysis. Numerous theoretical methods were used to calculate some parameters such as ionic radius, optical basicity, non-linear refractive index, and oxide ion polarizability. The mass attenuation coefficient MAC was obtained experimentally as well as theoretically by the Phy-X/PSD software programs and the obtained results were in very good agreement. The half-value layer HVL, mean free path (MFP), effective atomic number (Zeff), atomic cross-sections and electron cross-sections were evaluated for all the present glass samples. In addition, exposure build-up factor and energy exposure build-up factor were estimated for each glass up to penetration depths of 40 MFP. Moreover, the effective neutron removal cross-section (ƩR) was also calculated. The shielding properties of the prepared glass samples were compared with different concrete shielding materials, and commercial glasses, therefore, the prepared glasses outperformed all the aforementioned materials in terms of gamma ray shielding ability. [ABSTRACT FROM AUTHOR]

Gamma-ray irradiation is one of the most widely used mutagens worldwide. We previously conducted mutation breeding using gamma irradiation to develop new Citrus unshiu varieties. Among these mutants, Gwonje-early had an ovate shape, a protrusion of the upper part of the fruit, and a large fruit size compared with wild-type (WT) fruits. We investigated the external/internal morphological characteristics and fruit sugar/acid content of Gwonje-early. Additionally, we investigated genome-wide single-nucleotide polymorphisms (SNPs) and insertion/deletion (InDel) variants in Gwonje-early using whole-genome re-sequencing. Functional annotation by Gene Ontology analysis confirmed that InDels were more commonly annotated than SNPs. To identify specific molecular markers for Gwonje-early, allele-specific PCR was performed using homozygous SNPs detected via Gwonje-early genome re-sequencing. The GJ-SNP1 and GJ-SNP4 primer sets were effectively able to distinguish Gwonje-early from the WT and other commercial citrus varieties, demonstrating their use as specific molecular markers for Gwonje-early. These findings also have important implications in terms of intellectual property rights and the variety protection of Gwonje-early. Our results may provide insights into the understanding of morphological traits and the molecular breeding mechanisms of citrus species. [ABSTRACT FROM AUTHOR]

The synergistic effects on the 0.18 µm PPD CISs induced by neutron displacement damage and gamma ionization damage are investigated. The typical characterizations of the CISs induced by the neutron displacement damage and gamma ionization damage are presented separately. The CISs are irradiated by reactor neutron beams up to 1 × 1011 n/cm2 (1 MeV neutron equivalent fluence) and 60Co γ-rays up to the total ionizing dose level of 200 krad(Si) with different sequential order. The experimental results show that the mean dark signal increase in the CISs induced by reactor neutron radiation has not been influenced by previous 60Co γ-ray radiation. However, the mean dark signal increase in the CISs induced by 60Co γ-ray radiation has been remarkably influenced by previous reactor neutron radiation. The synergistic effects on the PPD CISs are discussed by combining the experimental results and the TCAD simulation results of radiation damage. [ABSTRACT FROM AUTHOR]

The present work aims to detect the effects of gamma ray radiation emitted from Co-60 on several blood parameters (PCV, Hb, WBCs and RBCs) of male chickens. Also, the potential antioxidant impact of grape seeds oil exposed to cold plasma as a protective material to lower the damage caused by gamma ray was tested for a long time and low dose rate. Healthy male chickens were used in this study which had an age range of 2 to 3 months and a weight range of 1.5 to 2 kg. Animals were kept in plastic cages (100 x 400 x 40 cm dimensions) within humidity and temperature preserved at limited values. Four experimental groups were included; the first was the un-exposed control. The second group was administered with a dose of grape seed extract. The third group was exposed to gamma ray radiation only. The fourth group was administered with a dose of grape seed extract and irradiated with gamma waves. Forty male chickens were used in this work as they were parted and administered with the selected doses. The control group was considered as the first group that contained 10 male chicken without being exposed to waves of gamma rays. The next group also contained 10 male chicken irradiated with 5 Gy/lh at interval 7 hour/day for 20 days as second group. Another group contained 10 male chicken and was dealt with oil of grape seed 400 mg/kg wt) with orally administered dose for 20 days as third group. The fourth group contained 10 male chicken irradiated with 5 Gy/h at interval of 7 hour/day for 20 days and dealt with orally administered dose (400 mg/kg wt) of grape seed oil for the same time. Overall groups (2-4), male chicken number became 30 used for 40.60 days at 7 hours per day. The schedule of work was achieved at 5 Gy/h of radiation equivalent dose with different exposure time for (20 and 40,60 days) on male chicken and at period 7 hours daily. The grape seed extract was bought from local market in Mosul City and filters from impure, as we found significant decrease in ratio of blood factors RBCs, WBCs, Hb and PCV with increasing of exposure time. This data changes with adding antioxidant materials as (grape seed oil) were the value of blood factors ratio enhancement by increasing the time of dose of these material compared with control group. The blood factors ratio of male chickens change with exposure time, with significant decrease by increasing exposure time, however, the protective material ( grape seed oil ) reduces the change in ratio % of the some blood factors compared with control group. [ABSTRACT FROM AUTHOR]

Prompt gamma rays of terbium emitted after (n,nʹγ) inelastic scattering reactions induced by irradiation of a terbium(III) hexahydrate (TbCl3·6H2O) sample with a beam of fission neutrons were investigated with the instrument FaNGaS (Fast Neutron-induced Gamma-ray Spectrometry) at an angle of 90° between neutron beam and detector. At sample position, the fast-neutron flux was 1.13 × 108 cm−2 s−1 and the neutron beam has an average energy of 2.30 MeV. We identified 124 prompt gamma lines from the 159Tb(n,nʹγ)159Tb reaction. Presence of prompt gamma rays from oxygen and chlorine was used for a concise verification of recently published results. Relative gamma-ray intensities, effective cross sections and fast-neutron spectrum-averaged partial production cross sections of the gamma lines are given including comparisons with available literature data. We found a reasonable agreement and the multitude of unreported lines adds decisive value to nuclear spectroscopy. Additionally, we estimated the detection limit of terbium as 1 mg for a counting time of 12 h. [ABSTRACT FROM AUTHOR]

The purpose of this research is assessing the significance of biological and physical seeds invigoration of different aged carrot seeds orders and study their field performance. An implementation of field experiment at station (A) College of Agricultural Engineering Sciences - University of Baghdad during fall season 2021-2022. The experimental design arranged using split plot within RCBD. As carrot seeds order considered main plots (primary P, secondary S, tertiary T) and seeds invigoration treatments sub plots (untreated seeds C0, biological B, Physical G, B+G) with three replicates (3X4X3). The interaction treatment PBG (biological+physical treated primary seeds order) reveals significance in majority of research traits such as field emergence percent, carrot total carotenoids, scavenging percent, total yield (97.67%,12.66mg.100g, 88%, 126.1 ton.ha-1) respectively in compare to untreated tertiary seeds order (TC0).

Optoelectronic devices are sensitive to changes in their performance due to various environmental operating conditions, including factors such as elevated temperatures, humidity levels, radiation exposure, and chemical exposure. These conditions can potentially lead to degradation in the device properties. As a result, specific applications demand optoelectronic devices that are capable of enduring and operating effectively in harsh environmental conditions. In this study, we investigate the effects of gamma irradiation on the structural, electrical, and optoelectronic properties of an Au/Porous Silicon/n-Si/Al heterojunction photodetector. The irradiation is conducted using gamma rays at various doses: 48.11, 96.06, and 143.57 kGy. The structural properties and figures of merit are examined before and after gamma irradiation. The samples are characterized before and after irradiation using XRD, scanning electron microscopy, current-voltage characteristics, responsivity, quantum efficiency, and minority carrier lifetime. The XRD results for porous silicon confirm the presence of structural defects resulting from irradiation. SEM images, taken after exposure to a dose of 143.57 kGy, reveal severe damage in the irradiated samples, characterized by a dense and randomly distributed arrangement of irregular pores and grains. [ABSTRACT FROM AUTHOR]

High-resolution two-phase flow data in the rod bundle are important in the development and validation of high-fidelity models for computational fluid dynamics and subchannel codes, in particular, those pertaining to light water reactor cooling systems. The Michigan Adiabatic Rod Bundle Flow Experiment (MARBLE) has been constructed as a modular assembly of an 8 × 8 lattice rod bundle to simulate scaled pressurized water reactor and boiling water reactor subchannel assemblies. To establish a high-spatial resolution database of the void fraction in the reactor fuel assembly geometries, tomographic measurements were performed with the High-Resolution Gamma-ray Tomography System, which was designed and built in house; the detector system has a spatial resolution of less than 1.0 mm using 240 LYSO (Lu1.8Y0.2SiO5) scintillators with a fan-beam array. In the present study, the local void fraction was measured with the MARBLE facility under various air-water flow conditions (jg = 0.04 to 0.85 m/s and jl = 0.12 to 0.77 m/s) covering from bubbly to cap-turbulent flows. The local void fraction was also successfully measured under nonuniform and asymmetric air bubble distribution conditions with an investigation of the effect of spacer grids and mixing vanes on void drift across subchannels. [ABSTRACT FROM AUTHOR]

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Silicon photomultipliers (SiPMs) are solid-state single-photon-sensitive detectors that show excellent performance in a wide range of applications. In FBK (Trento, Italy), we developed a position-sensitive SiPM technology, called “linearly graded” (LG-SiPM), which is based on an avalanche-current weighted-partitioning approach. It shows position reconstruction resolution below 250 μm on an 8 × 8 mm2 device area with four readout channels and minimal distortions. A recent development in terms of LG-SIPM is a larger chip version (10 × 10 mm2) based on FBK NUV-HD technology (near-ultraviolet sensitive), with a peak photon detection efficiency at 420 nm. Such a large-area detector with position sensitivity is very interesting in applications like MR-compatible PET, high-energy physics experiments, and readout of time-projection chambers, gamma and beta cameras, or scintillating fibers, with a reduced number of channels. These SiPMs were characterized in terms of noise, photon detection efficiency, and position resolution. We also developed tiles of 2 × 2 and 3 × 3 LG-SiPMs, reaching very large sensitive areas of 20 × 20 mm2 and 30 × 30 mm2. We implemented a “smart-channel” configuration, which allowed us to have just six output channels for the 2 × 2 elements and eight channels for the 3 × 3 element tiles, preserving a position resolution below 0.5 mm. These kinds of detectors provide a great advantage in compact and low-power applications by maintaining position sensitivity over large areas with a small number of channels.

Excellent thermal neutron absorption performance of boron expands the potential use of boron rich slag to prepare epoxy resin matrix nuclear shielding composites. However, shielding attenuation behaviors and mechanism of the composites against gamma rays are unclear. Based on the radiation protection theory, Phy-X/PSD, XCOM, and 60Co gamma ray source were integrated to obtain the shielding parameters of boron rich slag/epoxy resin composites at 0.015–15 MeV, which include mass attenuation coefficient (μt), linear attenuation coefficient (μ), half value thickness layer (HVL), electron density (Neff), effective atomic number (Zeff), exposure buildup factor (EBF) and exposure absorption buildup factor (EABF).μt, μ, HVL, Neff, Zeff, EBF and EABF are 0.02–7 cm2/g, 0.04–17 cm−1, 0.045–20 cm, 5–14, 3 × 1023–8 × 1023 electron/g, 0–2000, and 0–3500. Shielding performance is BS4, BS3, BS3, BS1 in descending order, but worse than ordinary concrete. μ and HVL of BS1-BS4 for 60Co gamma ray is 0.095–0.110 cm−1 and 6.3–7.2 cm. Shielding mechanism is main interactions for attenuation gamma ray by BS1-BS4 are elements with higher content or higher atomic number via Photoelectric Absorption at low energy range, and elements with higher content via Compton Scattering and Pair Production in Nuclear Field at middle and higher energy range.

In this study, the effect of gamma irradiation and chitosan on the shelf life of minced beef was investigated. A part of the meat sample was treated with a 2% chitosan solution and the other part was irradiated without chitosan at doses of 3, 5, and 7 kGy in the Gamma cell. Non-irradiated samples (controls) and irradiated samples were evaluated for microbial contamination, quality characteristics including color, odor, blood, and customer likelihood (overall acceptability) as well as lipid peroxidation. The results showed that both irradiation and chitosan treatment had a significant effect on reducing the microbial load of the meat, including all living microorganisms, Staphylococcus aureus, Escherichia coli, and Salmonella spp. During the storage period. There were no significant differences in the qualitative characteristics of irradiated and chitosan-treated samples and the non-irradiated control samples. Finally, according to the permissible level of lipid peroxidation, a dose of 3 kGy, was detected as a suitable dose for irradiation of the minced beef to increase its shelf life of it from 2 days to 7 days at 4°C. All meat packing components had good radiation resistance to this dose.

In this study, ethylene propylene diene monomer (EPDM)-lead monoxide (PbO)-magnetite (Fe3O4) composite was prepared and changes in its properties with different gamma irradiation doses (50, 100, 200, 300, 500, and 1000 kGy) were investigated. Characterizations of irradiated EPDM-metal oxide composites were performed by X-ray Diffractometer (XRD), Field Emission Scanning Electron Microscope (FESEM) and Universal Testing Machine (UTM). It was observed that the synthesized sample shows an amorphous nature beyond the 500 kGy irradiation dose. The FESEM morphographs of irradiated samples show an increase in fracture size with an increase in irradiation dose. The mechanical tests have shown that prepared samples retain their mechanical strength up to ∼100 kGy. In addition, the effect of thermal and electrical properties on irradiation dose has also been studied. The synthesized samples show good thermal stability up to ∼500 kGy. The AC conductivity of the synthesized EPDM-metal oxide composites has been observed to increase slightly with an increase in irradiation dose. It was observed that synthesized EPDM-metal oxide composites are relatively good radiation resistant candidates and can be used for radioactive waste disposal management applications.

The rapid breakdown anodizing method was used to produce (Bi, Bi2O3), (Pb, PbO2), and WO3 nanoparticles. These particles are utilized to fabricate gamma-ray shielding. The X-ray diffraction test displayed polycrystalline structures for all samples. Scanning electron microscope images illustrated the formation of (Bi, Bi2O3) and (Pb, PbO2) nanoplates and WO3 semi-sphere particles. Pressures of 318, 477, and 636 MPa were applied to reduce vacancies within the prepared powders and increase their densities. Cylindrical samples with a diameter of 14 mm and different thicknesses were formed. Utilizing gamma rays produced by sources like Am-241 (59.54 keV), Cs-137 (661.6 keV), Co-60 (1173 keV), and Co-60 (1332 keV), the shielding characteristics of the manufactured samples were studied. The linear attenuation coefficient, mass attenuation coefficient, and half-value layer were determined after the gamma flux was measured using a NaI(Tl) detector. The two attenuation coefficients were functions of the source energy, and they had the highest values for (Pb, PbO2) and the lowest for the WO3 sample. The atomic numbers of the elements used and the size of the voids inside the prepared powders played the greatest role in determining the values of the shielding parameters. [ABSTRACT FROM AUTHOR]

Maize (Zea mays) field trial was done at El-Ayat district, Giza governorate to evaluate some biocide compounds (Bacillus thuringiensis (Kurs.), Emamectin benzoate and Spinosad) exposed or non-exposed to gamma ray doses (120 and 480 Gy) to potentiate its lethality for fall armyworm, Spodoptera frugiperda (Smith) (Lepidoptera: Noctuidae) controlling purposes. Concentrations (1/2, 1/4, 1/8 and 1/16) of the recommended doses of biocides used in current maize field trials. The evaluation parameters of lethal doses efficacy and time-response for S. frugiperda controlling were used. Spinosad treatments were considered the best dose lethality for S. frugiperda controlling, followed by Emamectin benzoate and finally B. thuringiensis treatments. Meanwhile, Emamectin benzoate treatments gave the least time-response lethality than other treatments aforementioned. Gamma ray dose of 480 Gy, followed by 120 Gy can potentiate the biocide compounds of B. thuringiensis, Emamectin benzoate and Spinosad to become lethality more than the same compounds without exposing to gamma doses and saving the dose and the time-response for controlling S. frugiperda in maize plants. [ABSTRACT FROM AUTHOR]

In this study, we have investigated some hexaborides which are synthesized for the purpose of gamma-ray shielding. These materials were synthesized by the method of magnesiothermic reduction process in the open air, and stoichiometric amounts of M 2 O 3 , B 2 O 3 , and Mg (20% excess) were mixed where MIII is a three oxidation state lanthanide metal (DyIII, PrIII and YbIII) ion. Chemical and physical characteristics of the manufactured samples were determined by X-ray Diffractometry (XRD), Energy Dispersive X-ray Spectroscopy (EDX) and Scanning Electron Microscopy (SEM) analyzes. Gamma-ray shielding parameters were determined by using EGSnrc Monte Carlo (MC) code in 21.0 keV-1.728 MeV photon energy range. The calculated data were compared with the results calculated by Nist's XCOM database. The obtained results by using EGSnrc and XCOM program have shown successful consistency. It was concluded that the manufactured hexaborides have promising gamma shielding properties compared especially to lead and some shielding materials investigated earlier in the literature. [ABSTRACT FROM AUTHOR]