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Inorganic photocatalytic materials exhibiting a highly efficient response to ultraviolet-visible light spectrum have become a subject of widespread global interest. Nanocomposite metal oxides, particularly Nickel Oxide (NiO) and Zinc Oxide (ZnO), have gained attention for their diverse applications in gas sensing and photocatalytic processes. In this work, ZnO-NiO (ZnO_0.6NiO_0.4 and ZnO_0.4NiO_0.6) binary nanocomposites were synthesized by hydrothermal technique. The binary nanocomposites were analyzed by UV-Visible spectrophotometer, X-ray diffraction (XRD), photoluminescence (PL), Fourier transform infrared spectrophotometer (FTIR), energy dispersive X-ray spectroscopy (EDX), field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM). The XRD pattern revealed that the nanocomposites, the peaks of both ZnO and NiO are present indicating the presence of both crystal structures hexagonal wurtzite and cubic. The miller indices, crystallite size, microstrain and dislocation density were determined from the XRD plot. FESEM and TEM analyses showed the spherical morphology of the synthesized composites with an approximate size of 10nm. The detailed analysis of ZnO–NiO binary nanocomposite sensor characteristics in terms of sensitivity, selectivity, response and recovery time were carried out and the nanocomposites were found to be highly sensitive to CO₂ 100 ppm at 350^∘C and Cl₂ at 200^∘C. The photocatalytic degradation outcome showed 52% degradation of methylene blue at 10 ppm and 90w/m². These results suggest the potential utility of these binary nanocomposites in photocatalytic applications for the degradation of organic pollutants.

This paper reports the preparation of CuO and cobalt (Co)-doped CuO (Co:CuO) thin films (TFs) by a convenient spray pyrolysis reactor. Co concentration (conc.) was varied in CuO TFs from 2 to 8at.% at the step of 2at.%. In the FESEM images of undoped films, aggregations of nanoparticles were found. The surface morphology of CuO turned into porous and spongy nanostructures for 6at.% Co-doping. In XRD analysis, CuO film showed a monoclinic crystal structure with ($\bar{1}$11) peak occurrence. The crystallite size of the films was found to be between 5nm and 12nm. In UV–vis spectroscopy, the optical transmittance of Co:CuO films increased in the visible region and then saturated in the NIR light region. The highest transmittance of about 96% was found for the 6 at.% Co:CuO film. The band gap of Co:CuO increased with Co doping. Urbach energy, refractive index, dielectric constants and dispersion energy parameters were estimated. Electrical resistivity and carrier concentration were found in the order of ${10}^4\mathrm{\Omega }$-cm and ${10}^{17}$ cm${}^{-3}$, respectively. CuO films showed n-type conductivity for 4, 6 and 8at.% Co-doping. The figure of merit increased significantly with Co-doping up to 6at.%, indicating the enhancement in optoelectronic behavior.

Zinc oxide nanoparticles (ZnONPs) exhibit optical, electrical, and magnetic properties depending on their size and morphology. These properties are essential for using ZnONPs in various fields such as cosmetics, electronics and medicine. The properties and applications of ZnONPs depend on how they are synthesized, whether physical, chemical, or biological. This study aimed to produce ZnONPs by utilizing the leaf extract of Moringa oleifera and to study the effect of precursor molarity and leaf extract concentration on physical properties. The precipitated compound was characterized using X-ray diffraction (XRD), ultraviolet-visible spectroscopy (UV-Vis), and Scanning Electron Microscopy-Energy Dispersive X-ray spectroscopy (SEM-EDAX). Here, we prepared ZnONPs under four different molarity (0.2M, 0.3M 0.4M, and 0.5M) and two different leaf extract concentrations (10ml, 15ml). We analyzed the difference obtained in the average particle size in each case. From the XRD the major diffraction peaks are observed at 36.3, 47.53, 36.33, and 36 for 0.2M, 0.3M, 0.4M, and 0.5M, respectively. The average particle size was found to be in the range of 12–30nm. UV study was used to inspect the optical nature of the prepared ZnONPs and SEM confirmed the sample’s morphology. Investigations on the role of precursor molarity and leaf extract concentration in synthesizing ZnONPs indicated that average particle size increases with increasing precursor molarity and leaf extract concentration. The study also suggested that synthesizing metal oxide nanoparticles using botanical extract is an eco-friendly alternative to physical and chemical methods.

A renowned hard coating material (WC–Co) has the potential to overcome cavitation erosion (CE) in hydromachinery components. Hydro turbines that employ silt-filled water for electricity generation create a lot of metal waste due to erosion and cavitation caused by the particles. There is an urgent need for repair of hydropower components that have undergone damage due to cavitation. In this investigation, tungsten carbide composite coatings were produced on 13Cr4Ni (CA6NM) stainless steel substrates using the cold spray method. In order to create high-quality coatings, nitrogen was used as the propellant gas. The coating microstructures were characterized by EDS, SEM XRD, and microhardness tests. Cold-sprayed WC–Co-based coatings were exposed to enhance the cavitation erosion resistance of CA6NM steel. Cold spray coating prepared with WC-12/17Co powder has shown excellent wear-resistant properties due to higher hardness and lower porosity.

Radiobiological studies focused mainly on tracking the effects of photons (X and gamma rays) and high-energy charged particles over low energy ions, which raises interest in studying their biological effects. Therefore, the aim of this study is to investigate the interaction of low-energy hydrogen ions beam with xcortical bovine bone as a biological model. A hydrogen ions beam was used to bombard cortical bone with different fluences; 45, 70 and $90\times 10^{17}$ions/cm² at low energy of 5keV. The interaction of hydrogen ions with cortical bone was estimated theoretically by the SRIM/TRIM code. The obtained results showed that the average distribution range and the maximum depth for 5keV hydrogen ions are 91 and 150nm respectively. The energy losses from incident ions are 4.45keV for ionization, 170eV for phonons and 18eV for vacancies. Also, the energy losses from the recoil atoms are 119eV for ionization, 234eV for phonons and 8eV for vacancies. At the same time, the effect of low-energy hydrogen ions bombardment on the structure of bone was studied by X-ray diffraction (XRD) and FTIR.

The chemical bath deposition method (CBD) was used to create thin films of calcium zirconate on a glass substrate. After that, the samples were annealed for an hour at three different temperatures: $100^{\circ }$C, $200^{\circ }$C, and $300^{\circ }$C. The structural parameters of the samples like lattice strain, dislocation density and crystallite size were calculated from XRD analysis. The lattice strain was found to be very low. The crystallite size confirms the nano-size of the synthesized sample. From UV analysis, the optical energy direct bandgap was calculated in the range of 3.98–4.16eV. A higher annealing temperature of $300^{\circ }$C causes the thin film’s bandgap to diminish, confirming the calcium zirconate thin film’s broad bandgap characteristics. From SEM analysis, morphology, and adhesive nature was analyzed, and from AFM analysis, the grain size of the sample was found to be in 300nm.

Urea-doped barium tartrate (UBT) crystals were developed using the method of an aqueous solution. The crystal structure was determined through XRD analysis. Optical transmittance studies were conducted to analyze multiple linear optical parameters such as transmittance, band gap, refractive index, absorption coefficient and more. Vickers microhardness testing was performed to assess mechanical properties like hardness and yield strength. The efficiency of Second harmonic generation (SHG) was calculated for the harvested crystal. Laser damage threshold (LDT) testing was completed as well. Nonlinear optical characteristics were analyzed by applying the Z-scan method. Electronic polarizability was calculated for the UBT crystal.

Sc (0, 1, 2, 3 mol%): Tm: LiNbO₃ crystals were prepared by the Czochralski method. The inductively coupled plasma-atomic emission spectrometry (ICP-AES) analysis test shows that, as the concentration of Sc${}^{3+}$ increases, the effective segregation coefficient of Sc${}^{3+}$ and Tm${}^{3+}$ decreases. The X-ray diffraction (XRD) analysis test shows that the lattice size increases first and then decreases. The optical homogeneity analysis test shows that the birefringence gradient of the Sc-3 sample is $4.7\times 10^{-}5$$\mathrm{\Delta }$R/cm${}^{-1}$, which is 1/3 of pure LiNbO₃. Research demonstrates that when the Sc${}^{3+}$ content reaches or exceeds the threshold value, ${\mathrm{\text{Nb}}}_{\mathrm{\text{Li}}}^{4+}$ is replaced completely, thus introducing non-intrinsic defects ${\mathrm{\text{Sc}}}_{\mathrm{\text{Li}}}^{2+}$ and ${\mathrm{\text{Sc}}}_{\mathrm{\text{Nb}}}^{2-}$. These defects are able to form ${\mathrm{\text{Sc}}}_{\mathrm{\text{Li}}}^{2+}-{\mathrm{\text{Sc}}}_{\mathrm{\text{Nb}}}^{2-}$ charge self-compensating defect groups, it will greatly increase optical homogeneity.

This study intended to synthesize Nickel-doped Cerium oxide (Ni-CeO₂ NPs) nanoparticles using Pedalium Murex leaf extract. X-ray diffraction (XRD) was used to investigate the structure of the Ni-CeO₂ NPs. The XRD measurements showed that the Ni-CeO₂ NPs crystallized into the face-centered cubic system. The Ni(1%)-CeO₂ and Ni(3%)-CeO₂ NP’s crystallite sizes were between 47nm and 59nm. FTIR and Raman spectral studies were conducted to investigate the sample’s atomic vibrations and chemical bonding. Energy-dispersive X-ray study and field-emission scanning electron microscopy were performed to examine the surface texture and chemical assembly of the Ni-CeO₂ NPs. UV–Vis DRS spectrum study was performed to ascertain the reflectance characteristics and bandgap of Ni-CeO₂ NPs. The Ni(1%)-CeO₂ and Ni(3%)-CeO₂ NPs were found to have bandgaps of 2.73eV and 2.82eV, respectively. Electrochemical impedance spectroscopy and cyclic voltammetry were employed to explore the electrochemical nature of Ni-CeO₂ NPs and their capacitive properties at various scanning rates. Using the agar well-diffusion technique, the antifungal activities of Ni-CeO₂ NPs were assessed. The experimental findings illustrate the utility of Ni-CeO₂ NPs for supercapacitor electrode material and healthcare applications.

In this study, we report the biosynthesis of Nickel ferrite using Ocimum sanctum leaf extract (OSLE@NiFe₂O${}_4)$. The single-phase cubic spinel structure of the synthesized nickel ferrite was confirmed by powder X-ray diffraction (PXRD) analysis. Structural characteristics were further examined using FTIR analysis. Optical and morphological properties were investigated through UV–DRS and FESEM studies. The magnetic hysteresis loop (M-H loop) confirmed the superparamagnetic nature of OSLE@NiFe₂O₄ nanoparticles. The photocatalytic degradation of Congo Red (CR) dye by the synthesized OSLE@NiFe₂O₄ nanoparticles was explored, revealing a pseudo-first-order kinetic behavior with a degradation efficiency of 99.9% and a rate constant of 0.06min${}^{-1}$. These findings demonstrate the superior photocatalytic activity of the biosynthesized nickel ferrite nanoparticles, highlighting their significant potential for efficient dye removal.

In this work, M-type hexagonal ferrite nanoparticles having the composition ${\mathrm{\text{Ca}}}_{0.25}{\mathrm{\text{Ba}}}_{0.75}{\mathrm{\text{Cr}}}_x{\mathrm{\text{Fe}}}_{12-2x}{\mathrm{\text{O}}}_{19}$, where $x=(0.0,0.05,0.10,0.15,0.20)$ were fabricated by the sol–gel auto-combustion technique. The influence of chromium doping on structural, dielectric and magnetic characteristics was examined. XRD powder analysis revealed the geometry of single-phase hexaferrite with P63/mmc space group. The magnetoplumbite hexagonal structure was revealed by the X-ray diffraction analysis. Crystallite size, $a$ & $c$ lattice parameters, bulk density, X-ray density, cell volume and porosity were assessed. Crystallite size ranged from 39.54nm to 42.91nm. The X-ray density and bulk density were enhanced while porosity was decreased with the substitution of ${\mathrm{\text{Cr}}}^{3+}$cation. The morphology of the fabricated materials was inspected by the SEM analysis, which displays uniformly scattered particles with hexagonal platelet shape. The value of the dielectric constant is high in the low-frequency regime, and it decreases with increasing frequency. The dielectric constant decreased appreciably with the increase of ${\mathrm{\text{Cr}}}^{3+}$. Such observed dielectric and magnetic features are useful for different technological applications like microwave absorbers, voltage-controlled, dielectric resonators and recording media.

Nanoferrites of CoGd${}_x$Fe${}_{2-x}$O₄ ($x=0.0,0.03,0.06,0.09,0.12$ and $0.15)$ were synthesized via sol–gel auto combustion. The fashioned samples were examined by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FESEM), vibrating sample magnetometer and UV spectroscopic analysis. A cubic spinel phase with no impurities was confirmed by XRD. Doping with Gd${}^{3+}$ ions raises the crystallite size from 20nm to 25nm and the lattice constant from 8.351Å to 8.413Å. Formations of two significant bands are supported by FTIR spectra between 590cm${}^{-1}$ and 601cm${}^{-1}$, 403cm${}^{-1}$ and 407cm${}^{-1}$, which approve the establishment of ferrite structure. FESEM certified the formation of the nanoparticles and the fact that most of the grains are spherical and agglomerated and the EDX spectrographs certified the existence of the elemental compositions. With an increase in Gd${}^{3+}$ ion, saturation magnetization (M${}_s$) and remanence magnetization (M${}_r$) dropped from 132emu/g to 69emu/g and 93emu/g to 41emu/g, respectively. The coercivity (H${}_c$) increased with gadolinium and at the $x=0.15$ recording the extreme value of $H_c=1715$Oe. UV-spectroscopy studies authorized the samples’ semiconducting nature because band gap values were found from 2.108eV to 1.992eV.

In this research Zinc Nitrate Hexahydrate $(\mathrm{\text{Zn}}{({\mathrm{\text{NO}}}_3)}_2\cdot 6{\mathrm{\text{H}}}_2\mathrm{\text{O}})$ was used to synthesize Zinc oxide (ZnO) nanostructures and polyethylene glycol ($\mathrm{\text{PEG}})$ was used as the capping agent. During the synthesis process temperature and concentration of ammonium hydroxide $({\mathrm{\text{NH}}}_3\cdot {\mathrm{\text{H}}}_2\mathrm{\text{O}})$ and $\mathrm{\text{PEG}}$ were changed to control the size and morphology of the synthesized ZnO nanostructures. The structural and physical investigations of synthesized ZnO nanostructures were done using UV–Vis spectrophotometry, scanning electron microscopy (SEM) equipped with energy dispersive X-ray analysis (EDXA) and X-ray powder diffraction (XRD). The XRD analysis indicated an enhancement in crystallite size from 16.14nm to 17.98nm, which further increased to 43.39nm as the concentration of ${\mathrm{\text{NH}}}_3\cdot {\mathrm{\text{H}}}_2\mathrm{\text{O}}$ was varied from 5mL to 15mL (at the rate of increment of 5mL each time). While the crystallite decreases from 17.98nm to 4.75nm as the concentration of $\mathrm{\text{PEG}}$ increases from 0.5g to 1.5g (at the rate of increment of $\mathrm{\text{PEG}}$ 0.5g in each step). The maximum crystallite size of 47.15nm was observed in ZnO.7 at room temperature and decreased with increment of temperature. Optical absorption spectra showed that ZnO.5 has a maximum direct bandgap of 3.68eV at $50^{\circ }$C with the concentration of ${\mathrm{\text{NH}}}_3\cdot {\mathrm{\text{H}}}_2\mathrm{\text{O}}$ and $\mathrm{\text{PEG}}$ of 10mL and 1.5g respectively. Overall, the study demonstrated that the size, morphology and optical properties of ZnO nanostructures can be effectively controlled by varying temperature, the concentration ${\mathrm{\text{NH}}}_3\cdot {\mathrm{\text{H}}}_2\mathrm{\text{O}}$ and $\mathrm{\text{PEG}}$ during the synthesis process. The results could have significant implications for the development of ZnO-based nanoelectronics devices and other applications.

Polycrystalline ingots of CuInSe₂ and CuIn₃Se₅ were synthesized by melt-quench technique starting from the stoichiometric mixture of constituent elements. X-ray Diffraction (XRD) studies confirmed the single-phase nature of the materials. Compositional analysis by Particle Induced X-ray Emission (PIXE) showed that the compounds are near stoichiometric. Thin films of CuInSe₂ and CuIn₃Se₅ were grown from pre-synthesized CuInSe₂ and CuIn₃Se₅ powders. The films were polycrystalline, single-phase and near stoichiometric in nature, as indicated by Transmission Electron Microscopy (TEM) and PIXE studies.

This is a preliminary report for “the joint investigation between Japan and Egypt on Tutankhamun's golden mask”. This experiment was performed in the Egyptian Museum in Cairo using an XRDF (X-Ray Diffractometer equipped with x-ray Fluorescence spectrometer) setup invented by one of the authors (M. U.) and improved here. A diffraction pattern and a fluorescence spectrum can be obtained by the XRDF setup in the air from one and the same small area (1–2 mm in diameter) on a specimen.

The face and neck, and the other parts of the Tutankhamun's golden mask were composed of 23.2–23.5 K matrix covered with an 18 K Au-Ag-Cu thin layer, whitish gold in color, and with a 22.5 K Au-Ag-Cu thin layer, gold in color, respectively.

A dark blue material used for the nemes (headdress) was characterized with a new kind of glass paste which includ main components of Amarna blue and Egyptian blue, and is named here as Tutankhamun blue. A grayish blue material used for a false beard had a similar chemical composition to the dark blue one. Pectoral red and green beads were made of carnelian and amazonite, respectively.

We subjected ¹³⁷Cs-contaminated soil to stirring and particle classification to reduce the contaminated soil volume. ¹³⁷Cs activity as a function of particle diameter changed drastically as the weight ratio of soil/water varied; 85% of all ¹³⁷Cs was adsorbed to particles of minimum diameter after stirring. Soil argillites (smectites, vermiculites, and illites) adsorbed ¹³⁷Cs. We used X-ray diffraction (XRD) analysis to measure the soil contents; the ¹³⁷Cs distribution as a function of soil particle diameter mirrored the smectite levels revealed by the XRD peak intensities. Thus, smectic was the main absorbent of ¹³⁷Cs.

Natural FeTiO₃ (illuminate) and synthesized FeTiO₃, single crystals were characterized by Rutherford backscattering spectroscopy combined with channeling technique and particle-induced x-ray emission (RBS-C and PIXE). The results obtained by the ion beam analysis were supplemented by the x-ray diffraction analysis to identify the crystallographic phase. Oriented single crystals of synthesized FeTiO₃ were grown under the pressure control of CO₂ and H₂ mixture gas using a single-crystal floating zone technique. The crystal quality of synthesized FeTiO₃ single crystals could be improved by the thermal treatment but the exact pressure control is needed to avoid the precipitation of Fe₂O₃ even during the annealing procedure. Natural FeTiO₃ contains several kinds of impurities such as Mn, Mg, Na and Si. The synthesized samples contain Al, Si and Na which are around 100 ppm level as impurities. The PBS-C results of the natural sample imply that Mn impurities occupy the Fe sublattice in FeTiO₃ or in mixed phase between ilmenite and hematite.

A crystal-chemical study of trioctahedral micas previously characterized by single-crystal XRD has been performed by XANES spectroscopy at the Si and Al K edges. XANES, being a local structural probe, can investigate distortion and modification of the tetrahedral sheet with increasing Fe for Mg substitution in the octahedral sheet. Comparison of XANES spectra allows determining the size of the tetrahedral site occupied by either Si or Al. The Si-O distance remains essentially unchanged whereas the Al-O distance appears to increase. The behavior may be interpreted as a tilt of the tetrahedra, initially rotated to match the ideal mica geometry, with increasing Fe substitution in the octahedral sheet.

Samples with the nominal composition Bi₂Sr₂GdCu₂O_y in Bi-2212 where Gd replaces Ca as well as samples without Gd were prepared by solid-state reaction method. From the room temperature X-ray diffraction data, the samples were found to be similar to the single phase Bi-2212 structure. Impedance studies were performed from room temperature to 423 K at different frequencies in the range of 10 to 700 KHz. The AC conductivity increases with temperature and frequency, exhibiting frequency dispersion at low temperature region. The activation energy from AC conductivity in the high temperature region is found to be 0.432 eV. The permitivity increases with the increase in temperature and at 373 K it shows a maximum value exhibiting a dielectric loss. Complex impedance spectra are analyzed in terms of bulk relaxation and interfacial effects. The activation energy of the dipoles involved in the relaxation was estimated to be 0.482 eV. The universal power law of Jonscher is verified in the present system.

The epitaxial, single phase (100) Ba_0.5Sr_0.5TiO₃ (BST) films with thin interfacial layer of BST (x=0.4) were deposited on LAO (100) substrates using Pulse Laser Deposition (PLD). These films were characterized in terms of their phase formation and structural growth characteristics using X-ray diffraction and Atomic Force Microscopy respectively. The dielectric properties are strongly affected by the substrate type, post deposition annealing time, and temperature. In order to verify all these properties, thin interfacial-buffer layers of BST (10, 20, 50 nm) were introduced to relieve the stress induced between the film and the substrate. The variations of dielectric constant and ferroelectric properties of as deposited films are discussed in detail. The high tunability, low dielectric loss and low leakage current of these films make them attractive candidates for fabricating tunable dielectric devices. The observed dielectric properties of the BST-films are attributed to homo-epitaxial interfacial layer, which is responsible for the increase in the dielectric constant and tunability.