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In this study, metal oxides nanoparticles heterogeneous photocatalysts prepared by coprecipitation and ultrasonic techniques were used for diesel desulfurization. They were characterized by scanning electron microscope, powder X-ray diffraction, energy dispersive analysis, diffused reflectance spectra, photoluminescence analysis and BET surface area. The surface area of catalyst B is larger than catalyst A confirming its higher reactivity. X-ray reflectance spectroscopy was used to analyze the sulfur contents in feed. Thiophene was used as a model fuel to evaluate the photocatalytic activity of catalysts A and B. Using the Scherrer equation, sharp and intense signals suggesting their higher degrees of crystallinity, with average crystal sizes for ZnO, Bi2O3, catalysts A and B, respectively; of 18, 14.3, 29.7, and 23.8 nm. The operational parameters of the desulfurization process were optimized and have been studied and the maximum sulfur removal was achieved via a further solvent extraction step. A diesel fuel with a 24 and 19 ppm sulfur content and hence a total sulfur removal of 94.6% and 95.7% was acquired for catalysts A and B, respectively (sulfur compounds concentration in diesel fuel feedstock was 450 ppm). These findings demonstrated that photocatalysts A and B are good and effective catalysts for desulfurization of diesel fuel. [ABSTRACT FROM AUTHOR]

We have presented in the current work a novel idea for simulating the irradiation behaviors of the nuclear fuel pellets in nuclear reactors by using a one-dimensional defective phononic crystal (1D-DPnC) design was presented. The transmission spectra of the incident mechanical waves were considered basic data for expressing the characteristics of different nuclear fuel-pellets. Herein, the density, sound speed, and Young's modulus of the fuel-pellets represent the key parameters that are influenced by the irradiation behaviors of these pallets. Mixed plutonium–uranium oxide (MOX) nuclear fuel is considered the main fuel in the present study. In addition, a comparison is performed for this fuel with other types of nuclear fuels. Moreover, the mechanical properties of these MOX-pellets are dependent on the porosity, the ratio of oxygen-to-metal (O/M), and the plutonium (Pu-content). The theoretical treatments depend on the transfers matrix method to compute the transmission spectra through the 1D-DPnC. The numerical findings provided that the MOX-pellet has the highest performance compared to other fuel pellets and with sensitivity equal to 59.388 × 103 Hz s/m. It was also reported that the effects of the percentage of the O/M and Pu- content in MOX had a minor effect in a comparison with the impact of porosity. The theoretical simulation agreed extremely with the experimental data reported for these nuclear fuels. Because of the close relationship between sound speed and density, this sensor can be utilized to monitor the porosity, O/M, Pu-content, and density of fuel-pellets as a quick and non-destructive evaluation technique in a nuclear fuel fabrication laboratory. This article has proven theoretically that MOX fuel produced from nuclear waste of uranium dioxide and plutonium dioxide gives excellent results compared to other types of nuclear fuels, and this agrees with experimental researches. Thus, it may contribute in preserving the environment from nuclear waste, and this can be considered a novel kind of purification of environmental pollution treatment. [ABSTRACT FROM AUTHOR]

In this study, the main motivation of this work is desalination of water for irrigation arid area such as Sidri- Baba basins- south Sinai, Egypt. Also, the novelty of this work is modification of TFC surface membrane by mix of HA, DA and GO to get high performance of FO technique. Interfacial polymerization was employed to modify a thin-film composite (TFC) membrane for forward osmosis (FO) applications; moreover, graphene oxide (GO) nanosheets (GONs), a dopamine solution (DA), and naturally accessible humic acid (HA) were modified on a polyethersulfone (PES) substrate. The effects of the different quantities of GO, HA, and DA on the membrane surfaces, as well as their various cross-sectional morphologies and FO-desalination capabilities, were investigated. The integrated TFC membrane containing appropriate GO, HA, and DA blends outperformed the control membrane, obtaining high water flux, and high salt rejection. Furthermore,. [ABSTRACT FROM AUTHOR]

In the current work, we demonstrate a design to act as a Gamma-ray radiation dosimeter based on the one-dimensional photonic crystal (1D-PhC). The basic concept of the present dosimeter is based on a Porous Silicon (PSi) infiltrated by poly-vinyl alcohol (PVA)-polymer doped with crystal violet (CV) and carbol-fuchsine (CF) dyes. The mechanism of suggested dosimeter is based on the shift of the photonic bandgap (PBG) to higher wavelengths as exposed to gamma-ray radiation doses from 0 to 70 Gray (Gy). The basic axes of the current theoretical treatment are the transfers matrix method (TMM), Bruggeman's effective medium equation, and the fitted experimental data to the refractive index of the doped PVA-Polymer. The obtained results showed the proposed sensor is characterized by high stable sensitivity varied from (178–186 nm/ RIU) along an applied γ-dose from (10–70 Gy) in the visible range. In addition, we compared these results with previous researches. In addition, based on the our knowledge may be it is the first time that a 1D-PhC has been used for gamma-ray detection by using (PVA/CV + CF) based on Porous Silicon. [ABSTRACT FROM AUTHOR]

The power systems become operate closer to loadability limits; hence, the power systems static voltage stability assessment becomes an essential task in planning and operating for electric power systems to prevent voltage instability. In this paper, the improved moth flame optimization (IMFO) technique is applied for optimal location and size of (TCSC) with the aim of reducing load shedding, preventing voltage collapse, and enhancing the power system loadability. IMFO is developed to avoid the stagnating in local optima and improve the convergence characteristics of the conventional moth flame optimization. The loadability of the system is obtained using continuation power flow (CPF). The proposed approach is formulated by merging CPF with IMFO incorporated with TCSC. Multi-objective function is solved for minimization of loadability, load shedding, voltage stability index, and severity index. A contingency analysis is implemented on power system as two scenarios: The first scenario is outage of generator and the second scenario is outage line. Placement of TCSC has been determined by power flow analysis. The developed approach is tested on standard IEEE-30 bus system in normal operation, and contingency cases of generator and bus outage. The IMFO is compared to recent and well-known optimization techniques. The results reveal the efficiency of the proposed algorithm to reduce load shedding, continuous energy service to the customers and prevent occurrence of voltage collapse. [ABSTRACT FROM AUTHOR]

The fine-structure energy levels and lifetimes are calculated for the lowest 218 levels of the 2s22p5, 2s2p6, 2s22p43s, 2s22p43p, 2s22p43d, 2s2p53s, 2s2p53p, 2s2p53d, 2p63s, 2p63p, 2p63d, 2s22p44s, 2s22p44p, 2s22p44d, 2s2p54s, 2s2p54p, and 2s2p54d configurations in Sc XIII using the general-purpose relativistic atomic structure package (GRASP). The atomic data of the electric dipole (E1), electric quadrupole (E2), magnetic dipole (M1), and magnetic quadrupole (M2) transitions from the levels of 2s22p5, 2s2p6, 2s22p43s, 2s22p43p, 2s22p43d, 2s2p53s, 2s2p53p, 2s2p53d, 2p63s, 2p63p, and 2p63d configurations to the levels of the 2s22p5 and 2s2p6 configurations are presented. The GRASP results are compared with the other calculations and measurements. [ABSTRACT FROM AUTHOR]

This study involves a synthesis of bentonite/polyaniline composite (BE/PANI) of enhanced physicochemical properties as catalyst support for Ni2O3 photocatalyst. The change in the structural properties, morphological features, and optical behavior was addressed utilizing several analytic techniques. The characterization results reflected considerable enhancement in the specific surface area after the integration between bentonite and polyaniline (127 m2/g) and after loading of the campsite by Ni2O3 forming bentonite/polyaniline@Ni2O3 composite (BE/PANI@Ni2O3) (231 m2/g). Additionally, the band gap energy was reduced to 2.41 eV and 1.61 eV for BE/PANI and BE/PANI@Ni2O3, respectively, as compared to that of 3.4 eV for pure Ni2O3. The photocatalytic removal of safranin-O dye under sunlight exposure using BE/PANI@Ni2O3 as catalyst revealed great enhancement in the removal percentages by 63%, 75%, and 72.35% higher than bentonite, polyaniline, and Ni2O3, respectively. Five milligrams per liter of safranin-O dye can be completely removed from 100 ml water using 0.05 g of the composite after 90 min. The catalyst also was applied effectively in the removal of safranin-O dye from raw water samples as a realistic application of the synthetic composite. Synthetic BE/PANI@Ni2O3 as photocatalyst showed very high stability and can be used seven times as photocatalytic at amazing removal percentages. [ABSTRACT FROM AUTHOR]

M. M. S. Abo El-Fadl has not responded to correspondence from the Editors about this retraction. Retraction of: I Scientific Reports i https://doi.org/10.1038/s41598-022-25700-6, published online 08 December 2022 The Editors have retracted this Article at the request of the authors. [Extracted from the article]

As a part of systematic investigation of biologically active compound, m-phenylene diamine, new azo dye ligand was synthesized by diazotization of m-phenylene diamine and coupled with coupling compound, p-methoxy benzaldehyde. A new series of Cr(III), Mn(II), Fe(III), Co(II), Ni(II), Cu(II), Zn(II) and Cd(II) complexes derived from this azo dye ligand (L) were synthesized. The structures of the ligand and metal complexes were confirmed by elemental analysis, spectroscopic studies (IR, UV-Vis, H NMR, mass spectrometry, electronic spectra, magnetic susceptibility and ESR), conductivity measurements, thermogravimetric analyses (TG-DTG) and X-ray powder diffraction. The molar conductance measurements of the complexes in DMF determine electrolytic nature of the complexes. On the basis of elemental and thermal analyses, magnetic moment, electronic and ESR spectral studies, an octahedral geometry was assigned for metal complexes. XRD data reflect that azo dye ligand and its Cr(III), Mn(II), Fe(III), Co(II), Ni(II), Cu(II) and Zn(II) complexes are amorphous while Cd(II) complex is crystalline. Also, the newly synthesized azo dye ligand, in comparison with metal complexes, is screened for its antimicrobial and anticancer activity against breast cancer cell line (MCF7). The results showed that Mn(II), Ni(II) and Zn(II) metal complexes have higher anti-breast cancer activity than free ligand. [ABSTRACT FROM AUTHOR]

Energies, wavelengths, transition probabilities, oscillator strengths, and line strengths have been calculated for 4s4p-4s4p and 4s4p-4s4d transitions in gallium-like ions from Z = 60 to 65, for Nd XXX, Pm XXXI, Sm XXXII, Eu XXXIII, Gd XXXIV, and Tb XXXV using the fully relativistic multiconfi guration Dirac-Fock method. The correlation with the n = 4 complex and the quantum electrodynamic effects have been considered in the calculations. The obtained results have been compared with the available experimental and other theoretical results. [ABSTRACT FROM AUTHOR]

Energy levels, wavelengths, oscillator strengths, transition probabilities and lifetimes have been calculated for Be-like Xe, Cs, Ba, La, and Ce ions among the fine-structure levels of terms belonging to the 2s, 2s2p, 2p, 2s3s, 2s3p, 2s3d, and 2p3d configurations. The calculations have been performed using the fully relativistic multiconfiguration Dirac-Fock (MCDF) method, taking the quantum electrodynamic corrections (QED) into account. The results are compared with the available other theoretical results. [ABSTRACT FROM AUTHOR]

In this work, we present a new type of the one dimensional photonic crystals that contain graphene based nanocomposite and dielectric layers. Here, the nanocomposite layer is designed form graphene nanoparticles into a dielectric host material. By using transfers matrix method, Maxwell–Garnett formula, and Kubo formula, the properties of photonic band gap within visible and infrared regions are discussed. Our results reflect the significant effect of graphene on the optical characteristics of the nanocomposite layer and the transmittance properties as well. Thus, the tunability of the photonic band gaps could be expected. Meanwhile, we demonstrate the effect of the volume fraction of graphene's nanoparticles, the constituent materials thicknesses, the chemical potential and the permittivities of the host dielectric material on the transmittance properties of the proposed design. This design could be of potential interest in many fields of applications such as stop band filters and switches with high reflectivity. [ABSTRACT FROM AUTHOR]