Nanostructured Ni₅₀Ti₅₀ powders were prepared by mechanical alloying from elemental Ni and Ti micrometer-sized powders, using a planetary ball mill type Fritsch Pulverisette 7. In this study, the effect of milling time on the evolution of structural and microstructural parameters is investigated. Through Rietveld refinements of X-ray diffraction patterns, phase composition and structural/microstructural parameters such as lattice parameters, average crystallite size L, microstrain ε21/2, and stacking faults probability (SFP) in the frame of MAUD software have been obtained. For prolonged milling time, a mixture of amorphous phase, NiTi-martensite (B19′), and NiTi-austenite (B2) phases, in addition to FCC-Ni(Ti) and HCP-Ti(Ni) solid solutions, is formed. The crystallite size decreases to the nanometer scale while the internal strain increases. It is observed that, for longer milling time, plastic deformations introduce a large amount of stacking faults in HCP-Ti(Ni) rather than in FCC-Ni(Ti), which are mainly responsible for the observed large amount of the amorphous phase.

With the increasing applications of nuclear technology, radiation protection has become very important especially for the environment and the personnel close to radiation sources. Natural clays can be used potentially for shielding the X-ray radiations. In this study, the correlation between structural parameters and radiation shielding performance of natural clay extracted from Algerian Sahara (Adrar, Reggan, and Timimoune) was investigated. Phase composition and structural parameters (lattice parameters, average crystallite size, and microstrain) were determined by the Rietveld refinements of X-ray diffraction patterns in the frame of HighScore Plus software. The obtained results showed that the studied clays are nanocrystalline (nano-clay) since the calculated crystallite size was ≈3 nm for the feldspar phase. FTIR spectra confirmed the presence of all phases already detected by XRD analysis besides Biotite (around the band at 3558 cm⁻¹). The remaining bands corresponded to absorbed and adsorbed water (3432 cm⁻¹ and 1629 cm⁻¹, respectively) and atmospheric CO₂ (2356 cm⁻¹). The shielding properties (mass absorption coefficient—µ/ρ and radiative attenuation rate—RA) for (green-yellow, green, and red) clays of Adrar, (red, white, and white-red) clays of Reggan, and red clay of Timimoune at same energy level were examined. The results of clay samples were compared with each other. The obtained results indicated that the green clay of Adrar exhibited the superior radiation shielding, i.e., 99.8% and 243.4 cm²/g for radiative attenuation rate and mass absorption coefficient, respectively.

Introduction: Heavy metal contamination in water represents a major environmental and public health challenge because toxic ions frequently occur as complex multi-species mixtures rather than isolated pollutants. This study presents a numerical design and optimization of a surface plasmon resonance (SPR) sensor based on a LaF/Au/BaTiO₃/WS₂ heterostructure for monitoring refractive-index changes associated with mixed heavy metal ions in aqueous media. Methodology: The optical response of the multilayer sensor was evaluated using the transfer matrix method under TM-polarized illumination at 633 nm. Systematic optimization was performed for the prism substrate, Au thickness, dielectric oxide layer, and 2D nanomaterial interface. The final configuration consisted of a LaF prism, 50 nm Au film, 2.0 nm BaTiO₃ spacer, and 0.80 nm WS₂ monolayer. Sensor performance was assessed using resonance-angle shift, sensitivity, detection accuracy, quality factor, figure of merit, FWHM, attenuation, and estimated limit of detection. Results and Discussion: The optimized LaF/Au/BaTiO₃/WS₂ configuration produced stable simulated SPR responses across single, binary, quaternary, and five-ion heavy metal matrices. The WS₂ monolayer provided the highest angular displacement among the evaluated 2D materials, while BaTiO₃ improved field confinement and limited optical damping in the numerical model. The configuration maintained attenuation near 1.6%, FWHM values around 7.9°, detection accuracy between 0.030 and 0.032 deg⁻¹, and model-based refractometric LoD values down to 3.49 × 10⁻⁵ RIU under the assumed angular-resolution criterion. Conclusions: The proposed LaF/Au/BaTiO₃/WS₂ SPR configuration provides a numerical framework for label-free monitoring of refractive-index changes associated with complex heavy-metal-ion mixtures in contaminated water. Experimental fabrication and testing are required to validate the simulated performance.

The object of the research is the intriguing and versatile material known as coal that attracted a lot of attention lately because of its potential use in a variety of fields, including cutting-edge building materials, environmental remediation methods, and creative energy storage solutions. This study presents an extensive characterization of Algerian natural coal powders, employing a multifaceted analytical approach that includes Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), and Raman Spectroscopy, to reveal their physicochemical properties including morphology, particle size distribution, crystalline structure, and functional groups. The SEM analysis unveiled a heterogeneous morphology with a broad particle size distribution, indicative of the coal's complex structure. The XRD findings, refined using Rietveld analysis, distinguish Carbon (C) and Silicon Dioxide (SiO2) as the primary phases, with crystallite sizes measuring 18.7539 nm for C and 16.6291 nm for SiO2. These phases constitute 98.8 % and 12 % of the composition, respectively, while the presence of quartz underscores the coal’s geological background and its thermal resilience. Regarding the results of the FTIR spectroscopy, absorption peaks corresponding to various functional groups are highlighted, suggesting a rich organic and inorganic composition. Raman spectroscopy corroborates the presence of disordered and graphitic carbon structures, emphasizing the coal's potential for diverse applications. These findings underline the significance of Algerian coal powders for environmental remediation, energy storage, and advanced construction materials, contributing to the advancement of sustainable energy solutions.