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Water contamination by heavy metal ions poses a significant environmental threat. This study investigates (Mg0.4Co0.4Mn0.2)Fe2−2xSmxSnxO4 (0.000 ≤ x ≤ 0.050) ferrite nanoparticles (NPs) as eco‐friendly adsorbents for Cu(II), Cr(III), Fe(III), and Zn(II). X‐ray powder diffraction (XRD) confirmed sample purity, with crystallite size decreasing from 20.28 to 13.31 nm as x increased. Scanning and transmission electron microscopies revealed irregular morphology, whereas energy‐dispersive X‐ray showed successful dopant incorporation into the ferrite lattice. Brunauer–Emmett–Teller analysis indicated a surface area increase from 76.5 to 91.4 m2/g with doping. X‐ray photoelectron spectroscopy identified oxidation states, and Fourier transform infrared spectroscopy confirmed the spinel structure. Doping also increased the direct bandgap energy from 3.224 to 3.245 eV and decreased Urbach energy from 0.374 to 0.352 eV. The NPs achieved high removal efficiencies for Cr(III) at 93.3%, Fe(III) at 98.8%, and Zn(II) at 80.6%, though removal of Cu(II) was minimal. The optimal adsorption performance was observed at x = 0.050. Adsorption followed second‐order kinetics and fit the Langmuir isotherm. [ABSTRACT FROM AUTHOR]

Dye disposal in water has caused a serious environmental threat. Thus, ongoing research is driving efforts to explore solutions for this contaminant removal. Accordingly, the adsorption efficiency of ferrite nanoparticles has shown promising results for dye pollutant removal. Hence, in this study, Zn0.33Ni0.33Co0.33-xMgxFe2O4 nanoparticles were synthesized by chemical co-precipitation technique and studied under various operational parameters for the removal of methylene blue dye. The structural characterization of nanoparticles, held by XRD, confirms the successful phase formation with a small percentage of the hematite phase (< 8%). Additionally, the crystallite size decreased from 13.72 to 10.05 nm with Mg2+ increase from 0.00 up to 0.20. Consequently, the morphological characterization confirms the dependence of Mg2+ doping on the reduction of agglomeration between particles. The optical characterization was investigated by photoluminescence spectroscopy, highlighting an essential trend with the variation of excitation wavelength and Mg doping dependence. As the Mg content increases from 0.00 to 0.20, the surface area increases from 43.82 to 60.19 m2.g−1 whereas the pore diameter decreases from 16.65 to 12.49 nm. Among the synthesized samples, Zn0.33Ni0.33Co0.33Fe2O4 nanoparticles exhibited superior adsorption performance, achieving the highest adsorption capacity of 90.4 mg.g−1. In addition, the removal efficiency of methylene blue reached 95.8% for the Mg0.00 sample and 78.9% for the Mg0.20 sample, after a contact time of 30 min at pH 11. As the initial methylene blue concentration increased from 5 to 100 mg.L−1, the removal percentage in the presence of Mg0.00 decreased from 98.4 to 79.8%. The adsorption process followed second-order kinetics and was well-fitted with the Freundlich isotherm model. [ABSTRACT FROM AUTHOR]

Lead oxide (PbO) bulk and nanoparticles of two different sizes (A = 78 nm and B = 54 nm) are incorporated separately into the polystyrene matrix at various concentrations (0, 10, 15, 25, and 35 %) using roll mill mixing and compressing molding techniques. The X-ray narrow-spectrum series (N-series / ISO 4037-1) is then used to investigate the radiation attenuation capability of the novel polymer composite PS/PbO, as well as the effect of varying PbO particle sizes on shielding performance. The filler dispersion and chemical elemental analysis of the synthesized composite are investigated using scanning electron microscopy and energy-dispersive X-ray spectroscopy. To determine the mass attenuation coefficients μm, samples with various thicknesses of the synthesized composite are examined using a range of X-ray energies, and the experimental data are compared to theoretical values from NIST databases (XCOM and FFAST). The results indicate that either increasing the filler weight percentage or, decreasing the filler particle size, enhanced the attenuation parameters throughout all energies. The composite containing the smallest nanosize of PbO exhibited the maximum radiation shielding efficacy among all combinations and therefore, might be used to develop low-cost and lightweight X-ray shields.

(CoFe2O4)1-x/(Mg0.9Ni0.1O)x nanocomposites, with weight fraction x = 0, 0.1, 0.2, 0.4, 0.8 and 1, have been synthesized by co-precipitation method followed by high-speed ball milling technique. The structural and optical properties of the prepared samples have been studied. XRD analysis confirmed the formation of the two pure phases CoFe2O4 and Mg0.9Ni0.1O, without the formation of any impurities or minor phases in the nanocomposites. Transmission electron microscopy (TEM) followed by high-resolution TEM (HRTEM) and SAED were used to study the morphology, crystallinity and lattice spacing, respectively. TEM micrographs revealed the co-existence of spherical particles for both pure phases and their nanocomposites. The second-order kinetic model was employed to investigate the adsorption efficiency of the nanocomposites for removing malachite green (MG) dye from the solution. Among the prepared samples, superior adsorption performance was revealed by (CoFe2O4)0.2/(Mg0.9Ni0.1O)0.8 and Mg0.9Ni0.1O. (CoFe2O4)0.2/(Mg0.9Ni0.1O)0.8 nanocomposites were chosen as the best candidate among all samples as they possess magnetic properties which makes them easily removed from the solution after the adsorption process. Different adsorption isotherms (Langmuir, Freundlich, and Temkin isotherms) were used to determine the adsorption isotherm, and the results are consistent with the Langmuir theoretical model. The adsorption was further investigated by varying adsorbent concentration, pH of MG solution and reaction temperature. [ABSTRACT FROM AUTHOR]

Magnetic nanoparticles have emerged as a promising tool for wastewater treatment due to their unique properties. In this regard, Co0.33Mg0.33Ni0.33SmxFe2-xO4 (0.00 ≤ x ≤ 0.08) nanoparticles were prepared to examine their magnetic separation efficiency (MSE), photocatalytic, antibacterial, and antibiofilm performances. Pure nanoparticles, having the highest saturation magnetization (Ms = 31.87 emu/g), exhibit the highest MSE, where 95.6% of nanoparticles were separated after 20 min of applying a magnetic field of 150 mT. The catalytic performance of the prepared samples is examined by the photodegradation of rhodamine B (RhB) dye exposed to direct sunlight radiation. Improved photocatalytic activity is exhibited by Co0.33Mg0.33Ni0.33Sm0.04Fe1.96O4 nanoparticles, labeled as Sm0.04, where the rate of the degradation reaction is enhanced by 4.1 times compared to pure nanoparticles. Rising the pH and reaction temperature improves the rate of the photodegradation reaction of RhB. The incorporation of 15 wt% reduced graphene oxide (rGO) with Sm0.04 enhanced the rate of the reaction by 1.7 and 2.4 times compared with pure Sm0.04 sample and rGO, respectively. The antibacterial and antibiofilm activities against Escherichia coli, Leclercia adecarboxylata, Staphylococcus aureus, and Enterococcus faecium are assessed by the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) broth microdilution, the agar well diffusion, the time-kill assays, the biofilm formation, and destruction assays. The bacteria used in these assessments are isolated from wastewater. The nanoparticles exhibit a bacteriostatic activity, with a better effect against the Gram-positive isolates. Co0.33Mg0.33Ni0.33SmxFe2O4 (x = 0.00) nanoparticles have the best effect. The effect is exerted after 2–3 h of incubation. Gram-positive biofilms are more sensitive to nanoparticles. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate the effects of two sublethal doses of gossypol (GOS) (4 and 20 mg/kg of body weight), administered every other day, on some haematological, biochemical, enzymatic and electrolytic properties and amino and fatty acids in male rabbit blood plasma. The experiment lasted for 16 wk and included two phases: 1) administration period; rabbits were given the experimental doses of GOS for 8 wk; and 2) recovery period; rabbits were allowed 8 wk for complete withdrawal of drugs from the plasma. Results showed that low levels of gossypol increased (P

The extensive utilization of radiation is rapidly developing worldwide involving abundant fields like medical, industrial, research, and nuclear facilities. This makes the need for studying radiation shielding materials and their properties more urgent than ever. In the present study, bulk and nano ZnO were mixed by the same ratio each time (10, 20, 30, and 40 wt.%), with high-density polyethylene as a polymer matrix and characterized by X-ray diffraction. The results confirmed the good dispersion of bulk and nano ZnO particles within the polymer matrix. The prepared composite samples were used in different thicknesses as gamma ray shielding materials, and the heaviness was calculated and compared to lead. Using HPGe detector at specific energies (59.53, 356.01, 661.66, 1173.33, and 1332.50 keV) for different radioactive point sources (241Am, 133Ba, 137Cs, and 60Co), the mass attenuation coefficient for the samples was measured experimentally. Depending upon the obtained values, the linear attenuation coefficient, half-value layer, tenth value layer, heaviness and relaxation length were estimated. Using the XCOM database, the values of linear attenuation coefficient, mass attenuation coefficient, and other parameters were calculated theoretically for the bulk ZnO blended with high-density polyethylene. The obtained results were compared to the experimental values for nano and bulk ZnO blended with high density polyethylene. The radiation shielding behavior of nano ZnO blended with high density polyethylene was found to be more promising and efficient for radiation protection against gamma ray.

In this study, the structural and optical properties as well as the photocatalytic performance of Ni0.33Cu0.33Zn0.33Fe2O4 nanoparticles were investigated. These nanoparticles were prepared using the co-precipitation method by applying different calcination temperatures (773, 823, 873, 923, and 973 K). The X-ray diffraction analysis confirmed the presence of the cubic spinel ferrite phase without secondary phases. As the calcination temperature increased from 773 to 973 K, the crystallite and particle sizes of Ni0.33Cu0.33Zn0.33Fe2O4 nanoparticles increased from 12.84 to 20.19 nm and from 19.13 to 43.83 nm, respectively. Among the prepared samples, Ni0.33Cu0.33Zn0.33Fe2O4 nanoparticles calcined at 873 K revealed the highest value of band gap energy along with the lowest values of Urbach energy, refractive index, and optical and static dielectric constant. Additionally, the prepared samples were applied as photocatalysts for the degradation of aniline under ultraviolet irradiation. Improved photocatalytic performance was revealed by Ni0.33Cu0.33Zn0.33Fe2O4 nanoparticles calcined at 873 K. This was attributed to the slowest recombination rate of the electron–hole pairs as revealed from PL analysis. To further improve the photodegradation rate, the degradation reaction was studied by varying the catalyst amount, aniline concentration, pH mediums, and reaction temperatures. Increasing the pH and temperature boosted the degradation rate. Finally, the degradation reaction was carried out by incorporating Ni0.33Cu0.33Zn0.33Fe2O4 nanoparticles calcined at 873 K with different weight % of carbon quantum dots. The results revealed enhanced photocatalytic activity with k = 30 × 10−4 min−1 was achieved after combining 10 weight % of carbon quantum dots with Ni0.33Cu0.33Zn0.33Fe2O4 nanoparticles. [ABSTRACT FROM AUTHOR]

This study investigated the impact of samarium and lanthanum fluorides (SmF3 and LaF3) on the physical and mechanical properties of Tl0.8Hg0.2Ba2Ca2−xRxCu3O9−δ−yFy superconducting phases (specifically the (Tl, Hg)-1223 phase), where R = Sm and La, with 0.00   ≤     x     ≤   0.10 . The superconducting samples were synthesized using the solid-state reaction method. X-ray diffraction (XRD) verified the formation of the (Tl, Hg)-1223 phase without altering its tetragonal structure. Scanning electron micrographs (SEM) reveal the improvement of the grain size and inter-grain connectivity as Sm and La contents increased up to x = 0.025 . The electrical properties of (Tl, Hg)-1223 were studied using I-V and electrical resistivity measurements. Improved superconducting transition temperature (Tc) and transport critical current density (Jc) were observed up to x = 0.025 , beyond which they decreased substantially. Vickers microhardness (Hv) measurements were performed at room temperature to investigate their mechanical performance with various applied loads ( 0.49 – 9.80 N) and times ( 10 – 90   s). For both substitutions, the mechanical properties were enhanced up to an optimal value at x = 0.025 . All samples exhibited normal indentation size effect (ISE) behavior. The proportional sample resistance (PSR) model best explained Hv values among five theoretical models. Dislocation creep was the primary creep mechanism in the samples, according to indentation creep studies. [ABSTRACT FROM AUTHOR]

The characterization of (Mg–Ni–Co) nanoferrites doped with small different concentrations of gadolinium rare earth metal (Gd3+), prepared by the chemical co-precipitation method, is reported in this study. The XRD results reveal that the crystallite sizes, which are close to the particle size detected from TEM analysis, decrease upon adding Gd3+. Furthermore, the lattice constant a increases from 8.351 to 8.367 Å as the Gd3+ concentration (x) increases from 0.00 to 0.08. HRTEM images reveal the presence of different grains with different lattice plane orientations. Furthermore, the appearance of concentric circles in the SAED patterns verified the samples' polycrystalline nature. The presence of the active modes of the spinel structure was confirmed by the Raman analysis with a slight shift upon increasing the Gd3+ concentrations. Moreover, the photoluminescence (PL) analysis revealed the presence of a sharp peak in the UV region and structural defects in the prepared samples. Mössbauer spectroscopy and vibrating sample magnetometer (VSM) were used to examine the magnetic properties of the prepared samples. From the Mössbauer analysis, it was suggested that Gd3+ ions occupy the octahedral site. In addition, the saturation magnetization (Ms) and magnetocrystalline anisotropy (K) decreased from 31.87 to 15.76 emu/g and from 0.0057 to 0.0014 J/m3 with the increase of Gd3+ concentration from 0.00 to 0.08, respectively. Finally, different forms of the law of approach to saturation (LAS) for ferromagnetic materials were used for the fitting of M-H hysteresis loops at high applied fields. The obtained results show that the LAS model, mainly M = M s 1 - b H 2 + χ H , can effectively describe the doping of Gd3+ for all concentrations. This model exhibits well-fitting with high R2 values and provides relevant values of the magnetic parameters. [ABSTRACT FROM AUTHOR]