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The project's goal is to create new, low-cost materials with low density that can withstand the transport of γ-photons with low and intermediate energy. As a result, a set of four epoxy resins reinforced with different amounts of heavy metallic debris were created. By enlarging the waste component of the manufactured composites by 0–40 wt%, the density of the composites increased from 1.134 ± 0.022 to 1.560 ± 0.0312 g/cm3. The experimental assessment of the linear attenuation coefficient shows an increase with factors of 6.6, 2, and 1.5 times, respectively, for—photon energies of 33, 121, and 662 keV. The augmentation composites density has an impact on these parameters. The half-value thickness and the transmission factor for the fabricated composites decreased with enriching the heavy metallic waste composition, where the half-value thickness decreased from 5.95 to 3.08 cm as well as the transmission factor decreased from 89.01 to 79.86% with enriching the heavy metallic waste concentration from 0 to 40 wt%. The study shows the invalidity to use the fabricated samples to attenuate the γ-photons with energies higher than 662 keV, where the linear attenuation coefficient enhanced by a factor of 19% from 0.078 to 0.094 cm−1. [ABSTRACT FROM AUTHOR]

The study found that the activity concentrations of the radionuclides 238U, 232Th and 40K in the sandstone are 32 ± 13, 29.6 ± 12.2, and 132.6 ± 86.4 Bq kg−1, respectively. These values are lower than the reported worldwide limits of 33, 45, and 412 Bq kg−1. According to the present study, the absorbed dose rate (Dair), the annual effective dose, and the excess life time cancer were all found to be below the worldwide mean. Pearson correlation, PCA, and HCA were used to analyze the data and identify patterns in the relationship between radionuclides and radiological hazards. A statistical analysis of the sandstones showed that the radioactive elements 238U, 232Th and 40K are the main contributors to the radioactive risk. The study suggests that the sandstone is safe to use. The levels of radioactivity are not high enough to pose a risk to human health. [ABSTRACT FROM AUTHOR]

The distribution maps of natural radioelement (40K, 232Th and 238U) over the Wadi El Bohlog–Wadi Kam Amiri region of Egypt desert were shown. Granitic rocks, characteristic building materials of the study region, were analyzed: (1) the radionuclides contents were determined by using NaI detector; (2) minerals were investigated by an environmental scan electron microscope (ESEM). The average values of 238U, 232Th, 40K are higher than the worldwide average. This is due to the main mineral composition of the granitic rock samples, like thorite, uranothorite, kasolite, zircon and xenotime. Radiological hazards indexes were computed to evaluate the radioactive risk of these rocks to the public, showing high values exceeding the worldwide limits. [ABSTRACT FROM AUTHOR]

Six large Forbush decrease (FD) events of solar cycles 24 and 25 from 2008 to 2021 were recorded from five neutron monitoring stations in Rome, Moscow, Fort smith, Oulu, and Thule around the world. These events were recorded on (November 3, 2021, July 15, 2017, September 6, 2017, June 21, 2015, September 11, 2014, and March 7, 2012). An investigation has been carried out in an effort to comprehend the possible factors that played a role in the occurrence of the large FD. During the investigation, various extreme solar and interplanetary events were analyzed. These include sunspot numbers, the disturbance storm time (Dst) index, and the Ap index. We also analyzed the solar wind parameters like speed, density, temperature, and interplanetary magnetic field (IMF) Bz component. During the event period, there is a sudden decrease in the Dst index similar to the Forbush decrease. The increase in the number of sunspots that occurred prior to the beginning of the FD provides evidence that this phenomenon may be connected to the occurrence of solar flares, which further influences the variation in cosmic rays. It is found a substantial southerly Bz dip, a sharp increase in solar wind temperature and speed, and no discernible density influence was seen in any significant FD. [ABSTRACT FROM AUTHOR]

Urban surface deposited sediments (USDS) are unique indicators of local pollution that pose a potential threat to the living environment and human health. Ekaterinburg is a highly populated metropolitan area in Russia with rapid urbanization and industrialization activities. In Ekaterinburg's residential areas, about 35, 12, and 16 samples are represented by green zones, roads, driveways, and sidewalks, respectively. The total concentrations of heavy metals was detected using a chemical analyzer inductively coupled plasma mass spectrometry (ICP-MS). Zn, Sn, Sb, and Pb have the highest concentrations in the green zone, while V, Fe, Co, and Cu represent the utmost values on roads. Moreover, Mn and Ni are the prevailing metals in the fine sand fraction of driveways along with sidewalks. Broadly, the high pollution in the studied zones is generated by anthropogenic activities and traffic emissions. The potential ecological risk (RI) was observed in high risk (IR > 600), even though the results of all heavy metals reveal no adverse health effects from the considered noncarcinogenic metal for adults and children by different exposure pathways except the children's exposure to Co in case of the dermal contact, where the HI values of Co for children in the studied zones are higher than the proposed level (> 1). In all urban zones, the total carcinogenic risk (TLCR) values are predicted as a high potential inhalation exposure. [ABSTRACT FROM AUTHOR]

Study of gross beta activity was conducted in Russian cities Ekaterinburg, Rostov-on-Don, and Nizhny Novgorod. The cities were characterized by continental climate, although they are located in different geographical zones. The bulk urban samples were fractionated with three size fractions: dust (0.002–0.1 mm), fine sand (0.1–1 mm), and coarse sand (> 1 mm). Measurement setup equipped with beta radiometer BDPB-01 was designed to measure the low levels of gross beta-activity in a small amount of the obtained size-fractionated samples. According to the results of the study, the gross beta activity depends on the size fraction and the city. The highest beta activity concentration was found in the dust fraction which is about the same in all cities 0.8–0.9 Bq g−1. In size fractions of fine sand and coarse sand, the beta activity depends on the city. Among other cities, the highest average beta concentration was found in Ekaterinburg (0.8 and 0.6 Bq g−1 in fine and coarse sand fractions, respectively), while the lowest is 0.28 and 0.44 Bq g−1, respectively. The relationship of beta activity concentration with mineral and chemical composition is studied. Average beta activity in the different fractions of the surface–deposited sediment correlates with uranium, thorium, and organic matter concentration. The gross beta activity may be considered an indicator of high contribution of dust and high pollution with Pb, Cu, and Zn in the urban environment. [ABSTRACT FROM AUTHOR]

A passive technique using solid state nuclear track detectors was developed to detect the low-level gross alpha activity (Aα) in low-mass size-fractionated (< 10 g) samples of urban surface deposited sediment. The measurement system was calibrated using a source containing thorium monazite. The method was applied to measure radioactivity of the samples collected from various urban landscape zones in Ekaterinburg, Russia. The correlation between Aα, gross beta activity (Aβ) and potential harmful elements (PHE) concentrations was studied. It was found that the migration of natural radionuclides and PHE in the urban environment is associated with the same environmental processes. [ABSTRACT FROM AUTHOR]

Urban road sediments act as large basins for heavy metal contaminants produced as a result of natural processes and anthropogenic activities. This study is aimed at reviewing research over recent decades on heavy metal contamination in different cities around the world. The study reviews literature from Google Scholar, Web of Science, and Scopus journal publications. Cr, Cu, Pb, Zn, Ni, and Cd levels vary from one city to another. Based on the collected results, the pollution level and geoaccumulation index are estimated in each city. The levels of pollution in these cities range from low to extremely high, depending on the sources of pollution at each site (geogenic and anthropogenic sources, etc.) and factors like the distribution of industrial activities, population, and traffic emissions. This review shows that the development of modern cities and rapid urbanization are the major causes of heavy metal contamination in the environment. The contamination of the urban environment has different sources, both natural and anthropogenic in character. Solving the problem of heavy metal contamination in the urban environment requires the use of different techniques such as urban road control treatment and soil remediation. [ABSTRACT FROM AUTHOR]

Sediment samples were collected from urban zones in Ekaterinburg over the course of a year in order to analyze the gross beta activity. The bulk samples were categorized into three size groups: dust, fine sand, and coarse sand. A small amount of the obtained samples was used to develop a new method for measuring the concentration of gross-beta activity. The results show a statistically significant trend in beta-activity as the dust size of the samples increased between winter and autumn. The observed dependencies reflect geochemical processes in the formation and transportation of urban sediment. [ABSTRACT FROM AUTHOR]