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This paper thoroughly examines lanthanum-doped lead titanate (PbLaxTi(1−0.75x)O3), a perovskite-based ceramic material, focusing on its structural properties, vibrational behavior, and radiation shielding capabilities. Using advanced techniques like X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, and transmission electron microscopy (TEM), we explore the intricate relationship between lanthanum doping levels and material properties. Additionally, we assess its radiation shielding potential through metrics. Computational approaches employing the FLUKA code help evaluate theoretical values. Our findings reveal that increasing lanthanum concentration alters crystal atom arrangement, influences vibrational patterns, and enhances radiation shielding effectiveness. Increasing lanthanum concentration resulted in a maximum 7.55% rise in the mass attenuation coefficient (MAC) at 0.059 MeV. The half-value layer (HVL) decreased by 4.68% at 1.33 MeV, and the mean free path (MFP) decreased by 5.78% at 1.41 MeV with increased lanthanum ratio. Moreover, the radiation protection efficiency (RPE) increased from 30.7779 to 32.67442% at 0.059 MeV as lanthanum content increased. These findings offer valuable insights into material characteristics and suggest potential applications in enhancing radiation shielding for medical and industrial purposes. This comprehensive analysis provides practical insights for potential applications, particularly in medical or industrial radiation protection. The data-driven approach here paves the way for future research at the intersection of data science and material science, advancing material design and understanding doped perovskite materials. [ABSTRACT FROM AUTHOR]

The accumulations of beach placers along the shoreline of Hadhramout at As-Sufal area have been prospected and analyzed for their radiogenic and chemical characteristics for the first time. The activity concentrations of 226Ra, 232Th, and 40K in the beach placers' samples were measured by gamma-ray spectrometry using a 56% HPGe detector and found to be 1270±237, 2098±380, and 208±40Bqkg-1, respectively. The results established As-Sufal as a high natural background radiation area. The hazard indices predicted elevation of the external exposure of residents when sand soiled with beach placers from this area is used as a building material. Radium equivalents of beach placers were 8.6-14.3 times the maximum recommended for the safe use of materials in the construction of dwellings. The outdoor annual effective doses ranged from 1.68 up to ∼ 2.82 mSv considerably higher than the recommended 1-mSv dose limit for members of the general public. The beach placers at the study locations are dominated by TiO2, Fe2O3, and SiO2. Ir and Hf were found to be incorporated in Zr and Al compounds, respectively, and the anti-correlation of Zr with either Al or Hf indicates that Zr replaces both elements in the beach placers' grains. The radionuclides in beach placers seem to be attributed to Mg-, Ca-, Si-, and Zr-bearing minerals and not associated with Fe-bearing minerals. The heaviest fractions are mainly composed of TiO2, Fe2O3, and ZrO2. The TiO2-bearing minerals in the heaviest fractions contain V-rich portions. [ABSTRACT FROM AUTHOR]

Wadi Maryut Lake is one of the remaining parts of the ancient Lake Mareotis and is not mentioned in the scientific literature. For the first time, physical and chemical characteristics as well as elemental concentrations in sediment, water, soil, and plants were determined. The lowest metal pollution indices are in the northeastern end of the lake and tend to increase toward the other end. In lake aquatic environment, Al, Fe, K, Mn, Na, B, and Cr are more likely to exist in insoluble form in the southwestern part and in soluble form in the northeastern part. Using different approaches to assess sediment contamination demonstrates that sediments can be categorized as unpolluted. However, the geo-accumulation index suggests that two locations have low anthropogenic influence of Pb and the enrichment factors and the degree of contamination indicate that Co and Pb may be enriched in sediment of some locations. Comparisons with consensus-based sediment quality guidelines revealed that no sample exceeded the probable effect concentration for Cr, Cu, Ni, Pb, and Zn. The most mobile elements in sediment-water and soil-plant systems are Na, K, and Pb. In sediment-water system, Al, Fe, and Mn oxides have the major influence on scavenging of B, K, and Cr. Similarity in the occurrences of Mn, K, and Fe in soil and Mn and Fe in wild plant was found. This work demonstrates the state of decontamination of the lake and confirms its importance as a reference and comparative case for south Mediterranean coastal water bodies. [ABSTRACT FROM AUTHOR]