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In the presented work, B 4 C was irradiated with xenon swift heavy ions at the energy of 167 MeV. The irradiation of the substrate was done at room temperature to a fluence of 3.83 × 10 14 ion/cm 2 . The samples were then analyzed with the X-ray diffraction technique to study the structural modification, as it can probe the region of penetration of xenon atoms due to the low atomic number of the two elements involved in the material under study. The nano-cluster formation under ion irradiation was observed. Positron lifetime (PLT) calculations of the secondary point defects forming nanoclusters and introduced into the B 4 C substrate by hydrogen and helium implantation were also carried out with the Multigrid instead of the K-spAce (MIKA) simulation package. The X-ray diffraction results confirmed that the sample was B 4 C and it had a rhombohedral crystal structure. The X-ray diffraction indicated an increase in the lattice parameter due to the Swift heavy ion (SHI) irradiation. In B 12 -CCC, the difference between τ with the saturation of H or He in the defect is nearly 20 ps. Under the same conditions with B 11 C-CBC, there is approximately twice the value for the same deviation.

Particle-induced x-ray emission (PIXE) spectroscopy has been used to characterize soil samples from two relatively old gold mine sites (Iperindo and Itagunmodi) in the Ilesha schist belt of Southwestern Nigeria. This is with a view to identifying the indicator or pathfinder elements of gold for fingerprinting and toxicity potential assessment purposes. Average elemental concentrations of 19 major, minor, and trace elements were determined, and the geochemical data of Mn, Ni, Cu, Zn, Ag, As, Pb, and Au together with multivariate factor and cluster statistical analyses allowed to identify As and Ag as the pathfinder elements of gold. The high concentration of the determined pathfinder elements (As and Ag) as well as other toxic metals (Pb and Cu) implies a relatively high metal contamination risk to the miners and the ecosystem. The major hazard is represented by the abandoned mining wastes, pits, and ponds, already serving as fish ponds.