Optical and radiation shielding properties of PVC/BiVO4 nanocomposite.

This study investigates the physical and optical properties as well as the radiation shielding capacity of polyvinyl chloride (PVC) loaded with x% of bismuth vanadate (BiVO4) (x = 0, 1, 3, and 6 wt%). As a non-toxic nanofiller, the designed materials are low-cost, flexible, and lightweight plastic to replace traditional lead, which is toxic and dense. XRD patterns and FTIR spectra demonstrated a successful fabrication and complexation of nanocomposite films. In addition, the particle size, morphology, and elemental composition of the BiVO4 nanofiller were demonstrated through the utilization of TEM, SEM, and EDX spectra. The MCNP5 simulation code assessed the gamma-ray shielding effectiveness of four PVC + x% BiVO4 nanocomposites. The obtained mass attenuation coefficient data of the developed nanocomposites were comparable to the theoretical calculation performed with Phy-X/PSD software. Moreover, the initial stage in the computation of various shielding parameters, such as half-value layer, tenth value layer, and mean free path, besides the simulation of linear attenuation coefficient. The transmission factor declines while radiation protection efficiency increases with an increase in the proportion of BiVO4 nanofiller. Further, the current investigation seeks to evaluate the thickness equivalent (Xeq), effective atomic number (Zeff), and effective electron density (Neff) values as a function of the concentration of BiVO4 in a PVC matrix. The results obtained from the parameters indicate that incorporating BiVO4 into PVC can be an effective strategy for developing sustainable and lead-free polymer nanocomposites, with potential uses in radiation shielding applications.

Isotope signature and elemental characteristics of subsurface formations around deep-laying coal seams probed by means of atomic and nuclear-based techniques.

A systematic investigation on the isotopic and elemental signature, for both stable and radioactive elements, and mineral contents was performed to examine the characteristics of subsurface formations collected at different depths between 3.962 km and 4.115 km around deep-laying coal seams located under the Marmarica plateau in Egypt. Concentrations of major and minor oxides (Na2O, MgO, Al2O3, SiO2, SO3, K2O, CaO, TiO2, MnO, ΣFeO + Fe2O3, SrO, ZrO2, and BaO) were determined by X-ray fluorescence and dependencies among these concentrations revealed the type and sort of the formations. Organic contents were determined by Fourier Transform infrared spectroscopy to investigate the variation of the CO/CC bonding ratio with depth. Rare earth elements (REE), specifically Y, Sc, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu were determined by inductively coupled plasma mass spectrometry while actinoids were detected by the radioactive decay of its daughter nuclei. The results showed a high trapping of REE elements and actinoids in layers above the coal seams which indicates the occurrence of aqueous flow followed by possible sorption in these layers. The mobility of the fluid was investigated using the process radioactive decay series between Ra226 and Ac228 from one side and their daughters from the other side.

Theoretical investigation of selenium interferences in inductively coupled plasma mass spectrometry.

Structures, heats of formation, ionization energies, and proton affinities of selenium, argon dimer, argon-chlorine, and their hydrides (Se, SeH, SeH2, ArH, ArH2, Ar2, Ar2H, Ar2H2, ArCl, and ArHCl) are estimated by quantum chemistry calculations using G3, G4, and W1 composite methods and coupled cluster approach at the CCSD(T)/aug-cc-pVTZ levels. Thermochemistry of the reactions between ions A(+) = Se(•+), SeH(+), SeH2(•+), SeH3(+), Ar2(•+), Ar2H(+), Ar2H2(•+), Ar2H3(+), ArCl(+), ArClH(•+), and ArClH2(+) with various neutral gas G commonly used in dynamic reaction chamber-inductively coupled plasma-mass spectrometry (DRC-ICP-MS) (G = H2, CH4, NH3, O2, CO, CO2, NO, and N2O) has been investigated.