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The present study aimed to assess the radiological hazards associated with applying the investigated granite in the building materials and the infrastructures applications. The investigated granites are classified into four categories: El-Urf, barren, colourful and opaque. El Urf monzogranite intrudes metagabbro diorite complex with sharp contacts. Based on the activity concentrations, the environmental parameters such as absorbed dose rate (Dair), annual effective dose (AED), radium equivalent activity (Raeq), external (Hex) and internal (Hin) hazard indices were measured. The mineralized pegmatite is located in the southwestern foothill of the Gabal El Urf younger granite. It displays well-defined zonation of three zones: outer, middle and inner zones represented by potash feldspar, quartz and mica, respectively. The isorad map showed that El Urf monzogranite is barren (Up to 100 cps) surrounding an excavation of the studied pegmatite that exhibits moderate colorful mineralization (phase-I = 500–1500 cps) and anomalous opaque mineralization (phase-II = 1500–3500 cps) pegmatites. The obtained results of radionuclides activity concentrations illustrated that the Opaque granites have the highest values of 238U (561 ± 127 Bq kg−1), 232Th (4289 ± 891 Bq kg−1) and 40K (3002 ± 446 Bq kg−1) in the granites, which are higher than the recommended worldwide average. Many of the radiological hazard parameters were lesser than the international limits in the younger granites and barren pegmatites. All of these parameters were higher in the colorful and opaque mineralized pegmatites. The high activity and the elevated radiological hazard parameters in the mineralized pegmatites are revised to the presence of radioactive and radioelements bearing minerals, such as thorite, meta-autunite, kasolite, phurcalite, columbite, fergusonite, Xenotime and fluorapatite. Other instances of mineralization were also recorded as cassiterite, atacamite, galena, pyrite and iron oxide minerals. Thus, the granites with high radioactivity concentration cannot be applied in the different applications of building materials and ornamental stones.

Swelling soil leads to many types of constructional damages, deformations, and failures in the constructions’ roads, shoulders, and foundations. Depending on the amount of swell, they can be insignificant, moderate, or massive. This paper presents a method for swelling soil stabilization by adding rice husk powder (RHP) in variable percentages of 0, 5, 10, 15, 20, and 25 by weight of dry soil. The properties of swelling soil stabilization were investigated by various lab tests such as consistency limits (plastic limit, liquid limit, and plasticity index), swelling potential, swelling pressure, free swelling, and free swell index. The swelling soil was also mineralogically examined using X-ray diffraction of clay mineralogy. This stabilization reduced the plasticity from 56% (extremely high plasticity) to 4.5% (low plasticity). Swelling potential (S) and swelling pressure (SP) decreased by 48% to 45.5, 44.7, and 34.6%, from 1003 kN/m2 to 800, 653, and 489 kN/m2 for the partial replacement of the soil by 5%, 10%, and 15% RHP, respectively. The results show that the present approach is very efficient for improving the swelling soil properties and that the optimal amount of added RHP of the swelling soil is 15%. It will also be a database aimed at reducing construction risks in the future.

This study aimed to perform an investigation for the potential implementation of bismuth silicate glasses as novel shield equipment instead of ordinary shields in nuclear medicine facilities. Accordingly, a group of Bi2O3 reinforced silicate glass system were investigated and compared with ordinary shields in terms of their gamma-ray attenuation properties in diagnostic nuclear medicine radioisotope energies emitted from 99mTc, 111In, 67Ga, 123I, 131I, 81mKr, 201Tl, 133Xe. Mass attenuation coefficient (μm)&nbsp, results for glass samples were calculated comparatively with the XCOM program and MCNPX code. The gamma-ray attenuation parameters such as half value layer (HVL), tenth value layer (TVL), mean free path (MFP), effective atomic number (Zeff) were obtained in the diagnostic gamma ray energy range from 75 to 336 keV. To confirm the attenuation performance of superior sample, obtained results were extensively compared with ordinary shielding materials. According to the results obtained, BISI6 glass sample with the highest Bi2O3 additive has an excellent gamma-ray protection.

A new glass system (50−x)P2O5–20B2O3–5Al2O3–25Na2O–xCoO was manufactured using a standard melt quenching procedure, where 1≤ x ≤ 12 mol%. The characteristics of boro-phosphate-glasses containing CoO have been studied. The effect of CoO on the radiation-protective properties of glasses was established. The density of the prepared glasses as a function of CoO increased. XRD was used to check the vitreous structure of samples. Fourier-transform infrared (FTIR) spectroscopy was used to study the structure of each sample. FTIR demonstrated that connections grew as CoO/P2O5 levels increased, and the FTIR spectra shifted to higher wavenumbers. The increment of CoO converts non-bridging oxygens associated with phosphate structural units into bridging oxygens. This process increases the concentration of BO4 structural units and creates new, strong and stable bonds B–O–P, i.e., there is polymerization of the boro-phosphate glass network. With an increase in the ratio of CoO/P2O5 in the produced samples, ultrasonic velocities and elastic moduli were observed to increase. The coefficients of linear and mass attenuation, the transmittance of photons in relation to the photon energy, the efficiency of radiation protection in relation to the photon energy, and the thickness of the absorber were modeled using these two methods (experimental and theoretical). From the obtained values, it can be concluded that the 12Co sample containing 12 mol% will play the most influential role in radiation protection. An increase in the content of cobalt-I oxide led to a significant increase in the linear and mass attenuation coefficient values, which directly contributes to the development of the radiation-protective properties of glass.

The direct influence of La3+ ions on the gamma-ray shielding properties of cobalt-doped heavy metal borate glasses with the chemical formula 0.3CoO-(80-x)B2O3-19.7PbO-xLa2O3: x = 0, 0.5, 1, 1.5, and 2 mol% was examined herein. Several significant radiation shielding parameters were evaluated. The glass density was increased from 3.11 to 3.36 g/cm3 with increasing La3+ ion content from 0 to 2 mol%. The S5 glass sample, which contained the highest concentration of La3+ ions (2 mol%), had the maximum linear (μ) and mass (μm) attenuation coefficients for all photon energies entering, while the S1 glass sample free of La3+ ions possessed the minimum values of μ and μm. Both the half value layer (T1/2) and tenth value layer (TVL) of all investigated glasses showed a sim-ilar trend of (T1/2, TVL)S1 > (T1/2, TVL)S2 > (T1/2, TVL)S3 > (T1/2, TVL)S4 > (T1/2, TVL)S5. Our results re-vealed that the S5 sample had the highest effective atomic number (Zeff) values over the whole range of gamma-ray energy. S5 had the lowest exposure (EBF) and energy absorption (EABF) build-up factor values across the whole photon energy and penetration depth range. Our findings give a strong indication of the S5 sample’s superior gamma-ray shielding characteristics due to the highest contribution of lanthanum oxide. © 2021 by the authors. Licensee MDPI, Basel, Switzerland. Funding: The authors extend their appreciation to the Deanship of Scientific Research at King Kha-lid University for funding this work through the research group program under grant number R.G.P.1/1/42. The APC was covered by “Dunarea de Jos” University of Galati, Romania.

The Chilia branch is the north branch of the Danube River at the Romania-Ukraine border in the Danube Delta, it is a complex system with economic and ecological values. The surface water quality is a major concern and monitoring programs have been developed at the national and international level. The objective of this study was to evaluate the water quality of the Chilia branch in different sampling points from the mouth to the discharge in the Black Sea. The assessment of water quality was done at the individual level taking into account the nutrient concentrations and the standard limits for good ecological status and at integrative levels, using CCME WQI. The longitudinal distribution of Chilia branch water quality was done using GIS method. A total of 106 water samples were collected between 2013 and 2019 from five sampling points. At the individual level, the Chilia branch has a good ecological status except for its levels of total nitrogen, due to the organic nitrogen contribution in 2015. In 90% of nutrient concentrations, low values predominate and high values are considered extreme, only in 10% do high values predominate and low values are considered extreme concentrations. In equal percentages, 50% of the nutrient concentrations have a high degree of heterogeneity and the other 50% of concentration values are very close to the average values, with a high degree of homogeneity. CCME WQI method indicated that 39.93% of surface waters from the Chilia branch had an excellent quality, 45.45% a good quality, and only 14.62% a fair quality.

Characteristics of tellurite-tungstate-antimonate glasses containing heavy metal oxide were investigated in detail using two methods: the MCNPX Monte Carlo code and the Phy-X/PSD platform. The influence of Sm2O3, translocating with TeO2 at ratios of 0.2, 0.5, 0.8, 1, and 1.5 mol% on radiation shielding properties of glasses, was set forth with five glass structures determined according to the (75-x)TeO2-15Sb2O3-10WO3-xSm2O3 glass composition. Densities of the glasses were prepared by doping a low ratio of Sm2O3 that varied between 5.834 and 5.898 g/cm3. Sample densities, which have an important role in determining radiation shielding character, increased depending on the increase in Sm2O3 concentration. Effective removal cross-section (∑R) values against fast neutrons, as well as linear and mass attenuation coefficients, half-value layer, mean free path, variation of effective atomic number against photon energy, exposure, and energy built-up factors, were simulated with the help of these two methods. As a result of these estimates, it can be concluded that values obtained using both methods are consistent with each other. From the obtained values, it can be concluded that the SM1.5 sample containing 1.5 mol% would have the most efficient role in radiation shielding. An increase of Sm2O3 resulted in a significant increase in linear and mass attenuation coefficients and effective removal cross-section values belonging to fast neutrons and, in addition, resulted in a decrease in the half value layer. Doping HMO glasses with Sm2O3 was observed to contribute directly to the development of radiation shielding properties of the glass.

In this study, a group of heavy metal oxide glasses with a nominal composition of 55B2O3 + 19.5TeO2 + 10K2O + (15−x) PbO + xAl2O3 + 0.5Eu2O3 (where x = 0, 2.5, 5, 7.5, 10, 12.5, and 15 in wt.%) were investigated in terms of their nuclear radiation shielding properties. These glasses containing lanthanide-doped heavy metal oxide were envisioned to yield valuable results in respect to radiation shielding, and thus a detailed investigation was carried out, the obtained results were compared with traditional and new generation shields. Advanced simulation and theoretical methods have been utilized in a wide range of energy regions. Our results showed that the AL0.0 sample with the highest PbO contribution had superior shielding properties in the entire energy range. The effective removal of cross-sections for fast neutrons (ΣR) was also examined. The results indicated that AL5.0 had the greatest value. While increasing the concentration of Al2O3 in samples had a negative effect on the radiation shielding characteristics, it can be concluded that using PbO in the Eu3+ doped heavy metal oxide glasses could be a useful tool to keep gamma-ray shielding properties at a maximum level.

The radiation shielding characteristics of samples from two TeO2 and Sb2O3-based basic glass groups were investigated in this research. TeO2 and Sb2O3-based glasses were determined in the research as six samples with a composition of 10WO3-(x)MoO3-(90 − x)(TeO2/Sb2O3) (x = 10, 20, 30). A general purpose MCNPX Monte Carlo code and Phy-X/PSD platform were used to estimate the radiation shielding characteristics. Accordingly, the linear and mass attenuation coefficients, half value layer, mean free path, variation of the effective atomic number with photon energy, exposure and built-up energy factors, and effective removal cross-section values were determined. It was determined that the results that were produced using the two different techniques were consistent. Based on the collected data, the most remarkable findings were found to be associated with the sample classified as T80 (10WO3 + 10MoO3 + 80TeO2). The current study showed that material density was as equally important as composition in modifying radiation shielding characteristics. With the T80 sample with the greatest density (5.61 g/cm3) achieving the best results. Additionally, the acquired findings were compared to the radiation shielding characteristics of various glass and concrete materials. Increasing the quantity of MoO3 additive, a known heavy metal oxide, in these TeO2 and Sb2O3-based glasses may have a detrimental impact on the change in radiation shielding characteristics.

The present study was carried out on commercial types of Aswan granite used as building and decorative materials. Nearly 29 granitic rocks samples from 11 classes (black Aswan, red Aswan, dark Rosa, light Rosa, yellow Verdi, grey Shirka, Gandolla, Forsan, red Nefertiti, Royal, and white Halayeb) were collected from three stations near Aswan city for petrographical description and assessment of natural radioactivity. The petrographical study of granites was conducted by polarized-light microscope in order to determine their mineralogical composition and investigate their texture, the activity of the natural radionuclides 238U, Ra226, 232Th, and 40K was measured by gamma-ray spectrometry with a NaI(Tl) detector. The average values of the activities, 52.2 Bq kg−1, 57.8 Bq kg−1, 31.2 Bq kg−1, and 1055.7 Bq kg−1 of U-238, Th-232, Ra-226, and K-40, respectively, were higher than that the world average values of 35 Bq kg−1, 30 Bq kg−1 and 400 Bq kg−1 for 226Ra, 232Th, and 40K, respectively, according to the recommended levels from UNSCEAR reports. The minimum and maximum values obtained were compared with the value ranges from other locations in the Eastern Desert, highlighting the fact that that the maximum values obtained in this work are higher than those in other areas. According to the radiological hazards indices results, most samples lie in the permissible level ranges, suggesting their favorability for use as building materials. In contrast to that, some samples have some environmental parameters higher than the international levels, indicating their unsuitability as building materials.

This study aimed to investigate different types of glasses based on the 46V2O5-46P2O5-(8-x) B2O3-xCuO system in terms of their nuclear radiation shielding properties. Accordingly, five different CuO-doped vanadate glasses were investigated extensively to determine the necessary gamma shielding parameters along with effective conductivity at 300,000 and buildup factors. Phy-x PSD software was used for determination of these vital parameters. Furthermore, these parameters, such as half value layer, tenth value layer, and mean free path were investigated in a broad energy range between 0.015 and 15 MeV. The results revealed that the amount of CuO reinforced in each sample plays an essential role in determination of the shielding abilities of the samples. The sample with the highest CuO content had the highest linear attenuation coefficient and mass attenuation coefficient values. Additionally, the lowest mean free path, half value layer, and tenth value layer values were recorded for glass sample VPCu8. There was an inverse relation between the effective conductivity and effective atomic number and photon energy, that is, as energy increases, the effective conductivity and effective atomic number decreased rapidly, especially in the regions of low energy. Glass sample VPCu8 reported the highest values for both parameters. Moreover, glass sample VPCu8 had the lowest exposure buildup factor and energy absorption buildup factor values. Our findings showed that CuO-reinforced vanadate glass composition, namely 46V2O5-46P2O5-8CuO, with a glass density of 2.9235 g/cm3, was reported to have superior gamma ray attenuation properties. These results would be helpful for scientists in determining the most appropriate additive rare earth type, as well as the most appropriate glass composition, to offer shielding characteristics similar to those described above, taking into consideration the criteria for usage and the needs of the community. The results of this research will be useful to the scientific community in evaluating the prospective characteristics of CuO-doped glass systems and related glass compositions. CuO-doped glass systems and associated glass compositions have a wide range of properties.

Melt quenching technique is used for preparing glasses with chemical formula (70P2O5)−(16−x)CdO−(14ZnO)−(xEr2O3), (x = 1–6 mol%) . These glasses were named Er1, Er2, Er3, Er4, Er5, and Er6, respectively. Photon buildup factors, fast neutron absorption, and electron stopping of the prepared glasses were examined. Glasses’ density was varied from 3.390 ± 0.003 for the Er1 glass sample to 3.412 ± 0.003 for the Er6 glass sample. The Buildup factor (BUF) spectra have relatively higher values in the Compton Scattering (CS) dominated areas compared to both Photoelectric effect (PE), and Pair Production (PP) dominated energy regions. The highest BUF appeared at the Er atom K-absorption edge, whose intensity increases as the molar concentration of Er2O3 in the glasses increases. The photon absorption efficiency (PAE) of the glasses increases according to the trend (PAE)Er1 &lt, (PAE)Er2 &lt, (PAE)Er3 &lt, (PAE)Er4 &lt, (PAE)Er5 &lt, (PAE)Er6. Fast neutron removal cross-section, FNRC values of the glasses obtained via calculation varied from 0.1045–0.1039 cm−1 for Er1–Er6. Furthermore, the continuous slowing down approximation mode (CSDA) range enhances the kinetic energy of electrons for all glasses. Generally, results revealed that the investigated glasses could be applied for radiation shielding and dosimetric media.

The Dniester is one of the largest transboundary rivers of the Black Sea basin, and its lower reaches integrate the influence of climate change and hydropower plant (HPP) impact on the waterway. The decrease in precipitation and average annual air temperature increase and intensive hydroelectric construction have led to a decline in the total water content of the river, during the last 10 years, being below the long-term historical “norm”. The shifts in the river flow result in multidirectional seasonal dynamics of nutrient concentrations. During the modern period, a stabilization of nutrient concentrations takes place, being lower than at the peak of eutrophication in the 1970s–1980s, but higher than in the natural flow period. The construction of reservoirs leads to a long-term decline in silica concentrations, continuing in the modern period. The concentration of heavy metals and metalloids in water and bottom sediments of the river generally corresponds to the ecological status of “Moderate”. Biological communities show a high β-diversity of microalgae, but low diversity of plankton and benthic invertebrates. Biological communities respond to the impact of HPP in both the short- and long-term. Hydroelectric dams change the bioavailability of nutrients downstream which, in the long-term, causes shifts in phytoplankton composition, especially the reduction of Bacillariophyta due to the lack of silicates that are deposited in reservoirs. However, in the short-term, after the discharge from the HPP dam, the concentration of silicates and the proportion of diatoms increase. Long-term changes also include a decline in the proportion of Rotifera and an increase in Copepoda in the total abundance of zooplankton and the unification of the benthic community with an increase in the biomass of gastropods in the area, which can be considered as indicators of the impact of hydroelectric power plants. The saprobity index, calculated both for zooplankton and macrozoobenthos, characterised the water as moderately polluted, benthic biotic indexes (Biological monitoring working party (BMWP), Belgian Biotic Index (BBI), Danish Stream Fauna Index (DSFI)) calculated on macrozoobenthos described the condition as “low” quality.

The tremendous impact of natural and anthropogenic organic and inorganic substances continuously released into the environment requires a better understanding of the chemical status of aquatic ecosystems. Water contamination monitoring studies were performed for different classes of substances in different regions of the world. Reliable analytical methods and exposure assessment are the basis of a better management of water resources. Our research comprised publications from 2010 regarding the Lower Danube and North West Black Sea region, considering regulated and unregulated persistent and emerging pollutants. The frequently reported ones were: pharmaceuticals (carbamazepine, diclofenac, sulfamethoxazole, and trimethoprim), pesticides (atrazine, carbendazim, and metolachlor), endocrine disruptors—bisphenol A and estrone, polycyclic aromatic hydrocarbons, organochlorinated pesticides, and heavy metals (Cd, Zn, Pb, Hg, Cu, Cr). Seasonal variations were reported for both organic and inorganic contaminants. Microbial pollution was also a subject of the present review.

The purpose of this research was to investigate the shielding characteristics of high-amount heavy metal oxide and Eu3+-activated borate glasses based on 10La2O3–50HMO–(40–x) B2O3–xEu2O3 (x = 0, 0.5, 1, 2, and HMO = PbO, Bi2O3). Critical gamma radiation attenuation characteristics, particularly mass attenuation coefficients of investigated heavy metal oxide glass samples, were determined using Monte Carlo simulations and the Phy-x/PSD software. Following that, we looked at the half-value layer, mean free path, effective atomic number, and build-up factors across a broad energy range (0.015–15 MeV). According to the study’s results, the addition of Eu2O3 enhanced the mass attenuation coefficient and effective atomic number, while reducing the half-value layer, mean free path, and accumulation factors. In terms of gamma radiation attenuation, the LBi50BEu glass system surpassed the LPb50BEu glass system in terms of overall shielding properties against nuclear radiation. Additionally, the heavy metal oxide glass’ efficacy as a neutron shield was determined using fast neutron removal cross-sections (ΣR). LBi50BEu2 glass was shown to be more effective in preventing the penetration of charged particle radiation.