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We present the findings of an extensive examination on newly designed CdO-rich and transparent glass shields for nuclear medicine facilities in lieu of traditional and unfavorable materials, such as lead and concrete. Gamma-ray transmission factors of newly designed glass shields are determined using a variety of diagnostic, therapeutic, and research radioisotopes, including 67Ga, 57Co, 111In, 201Tl, 99mTc, 51Cr, 131I, 58Co, 137Cs, 133Ba, and 60Co. A general-purpose Monte Carlo code MCNPX (version 2.7.0) is used to determine the attenuation parameters of different material thicknesses. Next, the findings are compared using a standard concrete shielding material. The results indicate that adding more CdO to the glass composition improves the overall gamma-ray attenuation properties. As a result, among the heavy and transparent glasses developed, the C40 sample containing 40% CdO exhibited the best gamma-ray absorption properties against all radioisotopes. Furthermore, the gamma-ray absorption characteristics of this created high-density glass were shown to be better to those of a standard and heavy concrete sample. It can be concluded that the newly developed CdO-rich and transparent glass sample may be used in medical radiation fields where the radioisotopes examined are used in daily clinical and research applications.

Objectives This study investigates the effect of Annona muricata (AM) leaf extract against irradiation-induced damage by the evaluation of hepatic tissue and the levels of oxidative and inflammatory stress in the circulation. Methods An experimental study with 37 female Wistar albino rats randomized into four groups (controls and three intervention groups) was performed. The first interventional group (group 2) received 300 mg/kg of AM leaf extract by oral gavage once a day for 9 days, group 3 received a single dose of whole-body radiation (8.3 Gy) after a 9-day oral gavage treatment with saline, and the last group received the same irradiation of 8.3 Gy after being treated with 300 mg/kg of AM leaf extract by oral gavage once a day for 9 days. Results Radiation was found to elevate reactive oxygen species parameters, and AM administration before irradiation was found to decrease total oxidant status (TOS), increase caspase 9, and improve hepatic damage when compared with the group that received only irradiation. Conclusion The damage caused by irradiation may be ameliorated by the use of the AM extract, which appears to be effective in preventing oxidative stress and inflammatory activity.

We report a correlation outcome for mechanical and gamma-ray transmission properties of tellurite glasses by increasing tungsten(vi) oxide concentration in glass structure. The mechanical properties as well as Poisson’s ratio (σ) of the studied glasses are estimated by applying Makishima–Mackenzie model. Gamma-ray attenuation properties using various fundamental parameters are determined in 0.015–15 MeV energy range. Poisson’s ratio (σ) decreased from 0.43017 to 0.42711, while all elastic moduli increased linearly with the molar increment of either [WO3] or [TeO2] in the molecular structure of the glass network. Moreover, gamma-ray attenuation properties are enhanced as a function of increasing WO3 substitution amount from 30 to 50% mol in the glass structure. Half-value layer values at 15 MeV are found to be between 2.648 and 2.8614 cm. I4 samples with a composition of 20TeO2–50WO3–30GdF3 and density of 6.0530 g/cm3 was found to have superior material properties in terms of elastic and gamma-ray attenuation properties. It can be concluded that maximized WO3 contribution into the tellurite glasses may be considered as a critical tool in terms of establishing a symmetry between mechanical and gamma-ray attenuation properties for high-density tellurite glasses for their potential utilization in nuclear waste management, radiation shielding, and radioactive source transportation purposes.

The study area is situated in the central part of the Western Desert of Egypt between latitude 28°00′ to 30°00′ N and longitude 25°00′ to 30°00′ E. That region is distinguished by a featureless plain that is divided by depressions in Siwa, Qattara, and Bahariya. The purpose of the current study is to study the predominant structures in the area and how they relate to basin structure. Utilizing aerogravity data (Bouguer gravity, residual gravity, downward continuation, and Euler deconvolution) and aeromagnetic data (reduced to the northern Pole [RTP] anomalies and tilt derivative) is essential to accomplish this purpose. Through both qualitative analyses, these data were submitted to various processing and interpretation approaches. The subsurface structure configuration trending in E–W, N–S, NW–SE, NE–SW, ENE–WSW, and NNE–SSW directions has been simulated by utilizing aerogravity and aeromagnetic data. According to these maps, the study area is divided by around 44 faults. The study's findings indicated that the direction of the basement structure was almost NE–SW and N–S. The optimum Euler depth deconvolution at structure index, SI = 0 shows several features in the study area, including Sill, Dyke, Ribbon, and Step structures.

We report the role of the chemical modifications on various gamma-ray attenuation properties of four different tellurite glasses reinforced through WO3. The chemical compositions and glass densities are used in terms of determining some critical attenuation properties, such as linear and mass attenuation coefficients, half value layer, and effective atomic number values. Based on the rise in density, it was determined that the maximum concentration of WO3 also resulted in a significant change in the overall gamma-ray absorption properties, when all of the study’s findings were examined. It was observed that the glass sample, in which TeO2 and WO3 were 40 mol%, had the highest density. It was found that this glass with the highest density has the highest linear attenuation coefficient and mass attenuation coefficient and the lowest half value layer among the four samples specified. This demonstrates that WO3 inclusion is a functional component that may be used in tellurium glasses and is a suitable material for situations requiring increased gamma-ray absorption properties.

Austenitic stainless steels (SSs) are commonly used as in-core and surrounding structural materials in today’s industrial BWR and PWR systems. Such adaptable steels have also been the primary materials studied and used in several advanced nuclear reactor technologies, such as fast breeding and magnetic fusion reactors. In this study, some critical material properties, such as structural, physical, and radiation-shielding properties of REX-734 and 316L SS, were experimentally evaluated and compared to those of a number of other alloys. In addition to homogeneous element distribution, both alloys exhibit strong crystal orientation. The REX-734 alloy has a tensile strength of 1,259 MPa, whereas the 316L SS alloy has a tensile strength of 495 MPa. Moreover, nitrogen in the REX-734 alloy formed ultra-hard nitrides with Cr, Nb, and Si and precipitated into the structure and increased the strength. According to our findings, the mass attenuation coefficient values of the 316L SS sample were slightly higher than those of the REX-734 sample at all energies. It can be concluded that the REX-734 sample, with its exceptional strength qualities and excellent radiation attenuation capabilities, may be a viable nuclear power plant material for future investigations.

The aim of this study was to evaluate the temporal variations of selected heavy metals level in anaerobic fermented and dewatered sewage sludge. Sewage sludge samples were collected in different seasons and years from three municipal wastewater treatment plants (WWTPs) located in Northern Greece, in Kavala (Kavala and Palio localities) and Drama (Drama locality) Prefectures. An investigation of the potential of sludge utilization in agriculture was performed, based on the comparison of average total heavy metal concentrations and of chromium species (hexavalent, trivalent) concentrations with the allowed values according to the Council Directive 86/278/EEC and Greek national legislation (Joint Cabinet Decision 80568/4225/91) guidelines. In this regard, all the investigated heavy metals (Cd, Cr, Cu, Ni, Pb, Zn, Hg) and chromium species Cr(VI) and Cr(III) have average concentrations (dry matter weight) well below the legislated thresholds for soil application, as following: 2.12 mg kg−1 Cd; 103.7 mg kg−1 Cr; 136.4 mg kg−1 Cu; < 0.2 mg kg−1 Hg; 29.1 mg kg−1 Ni; 62.0 mg kg−1 Pb; 1253.2 mg kg−1 Zn; 1.56 mg kg−1 Cr(VI) and 115.7 mg kg−1 Cr(III). Values of relative standard deviation (RSD) indicate a low or moderate temporal variability for domestic-related metals Zn (10.3-14.7%), Pb (27.9-44.5%) and Cu (33.5-34.2%), and high variability for the metals of mixed origin or predominantly resulted from commercial activities, such as Ni (42.4-50.7%), Cd (44.3-85.5%) and Cr (58.2-102.0%). For some elements the seasonal occurrence pattern is the same for Kavala and Palio sludge, as following: a) Cd and Cr: spring>summer>winter; b) Cu, Ni and Pb: winter>spring>summer. On average, in summer months (dry season) metal concentrations are lower than in spring and winter (wet seasons), with the exception of Zn. For Kavala and Palio the results demonstrate that the increased number of inhabitants (almost doubled) in summer time due to tourism does not influence the metal levels in sludge. Comparing the results obtained for similar spring-summer-winter sequences in 2007 and 2010/11 and for the spring season in 2007, 2008 and 2010, it can be noticed that, in general, the average heavy metal contents show an increasing tendency towards the last year. In all the measurement periods, the Palio sludge had the highest metal contents and Kavala sludge the lowest, leading to the conclusion that the WWTP operating process rather than population has a significant effect upon the heavy metal content of sludge. Cr(VI)/Cr(total) concentration ratios are higher for Kavala sludge in the majority of sampling campaigns, followed by Drama and Palio sludge. The metals which present moderate to strong positive correlation have common origin, which could be a domestic-commercial mixed source.

Instrumental neutron activation analysis (INAA) was used to determine concentrations of 42 elements in samples of surface soil collected at seven sites polluted from various anthropogenic activities and a control site in a relatively clean area. Elements studied were Ag, Al, As, Au, Ba, Br, Ca, Cd, Ce, Co, Cr, Cs, Eu, Fe, Gd, Hf, Hg, K, La, Lu, Mg, Mn, Mo, Na, Nd, Ni, Rb, Sb, Sc, Se, Sm, Sr, Ta, Tb, Th, Ti, U, V, W, Yb, Zn, and Zr. The results are compared with data for trace elements atmospheric deposition in lichen transplants from the same sites. The most severe soil contamination was observed at Copsa Mica from non-ferrous metallurgy. Appreciable soil contamination was also indicated at Baia Mare (non-ferrous mining and metallurgy), Deva (coal-fired power plant, cement and building materials industry), Galati (ferrous metallurgy), Magurele and Afumati (general urban pollution), and Oradea (chemical and light industries). In most cases excessive levels of toxic metals in soils matched correspondingly high values in lichen transplants. Compared to Romanian norms, legal upper limits were exceeded for Zn and Cd at Copsa Mica. Also, As and Sb occurred in excessive levels at given sites.

In this work instrumental neutron activation analysis (INAA) was applied to investigate a total of 30 samples of metallurgical raw materials (sinter, pellets, coke) and related finished products (pig iron, slag, blast-furnace flue dust) sampled from the same blast furnace discharge in the ironmaking process in the Integrated Iron and Steel Works of Galati (Romania). The transfer efficiencies of minor elements As, Cu, K, Na, V and W from raw materials - iron-bearing components (sinter, pellets) and coke - to pig iron and their losses in slag and flue dust have been determined and a discussion of the behaviour of each element during the blast furnace process was done.