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The electronic, magnetic and optical properties of the double perovskites Ca2NiOsO6 and Fe-doped derivative were calculated using the full potential linearized augmented plane wave technique through the GGA + U with PBE exchange correlation functionals. The calculations show that both of the systems are half-metallic with Fe-doped system as a ferromagnet, whereas the undoped system shows the ferrimagnetic ordering. Additionally, the study is extended for calculating the Mott parameters through dynamical mean field theory (DMFT) with the maximum entropy model (MEM). It is found that the MIT model parameters (U, β) for Ca2NiOsO6 and Ca2Fe 0. 5 0 Ni 0. 5 0 OsO6 systems are (5.7 eV, 6.0 (eV) − 1 ) and (6.0 eV, 6.0 (eV) − 1 ), respectively. Furthermore, the calculations agree with optical Drude peak analysis. The optical conductivity, reflectivity, absorptivity, ELOSS function, dielectric function refractive index and sum-rule are also explored in relation to the photoinduced behaviors of the materials. [ABSTRACT FROM AUTHOR]

This paper presents a simulation of the structural and optoelectronic properties of Scandium Arsenide (ScAs) and Aluminum Arsenide (AlAs) compounds. Theoretical modeling was performed using ab initio first-principles calculations, specifically the density functional theory (DFT), and the Mindlab numerical software. The software used two methods: the full-potential muffin-tin orbital method (FP-LMTO) and the full-potential plane-wave method (FP-LAPW). These two methods are employed to solve the Schrödinger equation. The exchange correlation effects have been computed using two different approximations: the generalized gradient approximation (GGA) and the local density approximation (LDA). Our findings indicate that the zinc blende structure (B3) is the stable phase, while the Wurtzite phase (B4) is metastable for the AlAs compound. On the other hand, the ScAs compound crystallizes in the NaCl phase (B1). The AlAs compounds undergo three phase transitions: B3→B4, B3→B2 and B3→B1. In contrast, ScAs does not undergo any transition. The obtained results for equilibrium energies, lattice parameters and gap energies are in closer agreement with the experimental and theoretical data. The AlAs compound exhibits a semiconducting character, while ScAs exhibits a semi-metallic character. Additionally, the refractive index of these two compounds is similar to that of silicon, which is crucial for their application in photovoltaic cells. [ABSTRACT FROM AUTHOR]

In this paper, we examine the application of density functional theory (DFT) to determine the structural and optoelectronic properties of the tetragonal monochalcogenide TlSe, in order to assess its suitability for use in optoelectronic devices, photovoltaics, etc. These calculations are carried out using the full-potential linearized augmented plane wave (FP-LAPW) method, implemented in Wien2k software. The monochalcogenide compound TlSe adopts a tetragonal structure with I4/mcm space group symmetry (No. 140). We determined the ground-state values by calculating the total energy as a function of volume, relaxing the atomic positions for each volume, in order to minimize both the strength and the c/a ratio. Equilibrium structural parameters are derived from the internal structure parameters by fitting the total energy versus volume results with the Birch-Murnaghan equation of state. We studied the electronic properties using two approaches, GGA and TB-mbj. The latter approach gave an energy gap of 0.49 eV, close to the experimental value, which led us to adopt the TB-mbj approach in calculating optical properties such as the complex dielectric function ε ω , complex refractive index N ω , optical reflectivity R ω , energy loss function L ω , optical absorption α ω and optical conductivity σ ω . [ABSTRACT FROM AUTHOR]

XCoP (XTi, Zr, Hf) half Heusler alloys are investigated through density functional theory in stable non‐magnetic phase. The exchange‐correlation functional Generalized Gradient Approximation (GGA) is used to study these alloys. The equilibrium lattice constants and corresponding ground state energies of the studied alloys are calculated in stable γ‐phase. All these three reported alloys exhibit semiconducting behavior with corresponding bandgap values of 1.40, 1.29, and 1.38 eV for TiCoP, ZrCoP, and HfCoP, respectively. The studied alloys are mechanically stable and ductile in nature. The obtained thermoelectric figure of merit for p‐type TiCoP, ZrCoP and HfCoP are 0.5, 0.6, and 0.7 at 1200 K. Similarly, the figure of merit obtained for n‐type TiCoP, ZrCoP, HfCoP are 0.54, 0.37, and 0.31, respectively, at the same temperature. The investigated favorable transport properties of these alloys show that they are the potential candidates for waste heat energy harvesting application. [ABSTRACT FROM AUTHOR]

In this report, we have investigated the CsMgCl3 compound with the help of the WIEN2K software package. The structural and electronic properties are performed using the full potential augmented plane wave (FP-LAPW) method with the generalised gradient approximation (GGA) approximation as exchange correlation potentials. We used the Birch-Murnaghan equation (BME) to find the structural properties of the material. These include the lattice parameter, the bulk modulus, the first derivative of the bulk modulus, the minimum energy, and the volume. The structural properties match up with the experimental data. Electronic properties in terms of the band structure (BS) and total and partial density of state (T-DOS and P-DOS) profiles of CsMgCl3 using GGA potentials exhibit an indirect wide energy band gap of 5.35 eV. All these properties show that the CsMgCl3 compound is used as a perovskite in solar cells.

A burnable absorber is a material used in nuclear reactors to manage reactivity and extend operational cycles by absorbing neutrons. Gadolinium oxide (Gd2O3) is a prevalent burnable absorber employed in nuclear reactors. By utilizing density functional theory (DFT) within a first-principles framework, a comprehensive exploration into the physical characteristics of the predicted tetragonal phase of Gd2O3 has been effectively conducted. The investigation encompasses structural, electronic, magnetic, elastic, mechanical, bonding, thermophysical, and optical aspects. Since tetragonal Gd2O3 has not been experimentally synthesized, the stability of the tetragonal phase is confirmed through assessments of its structural, lattice dynamical, thermodynamic, and mechanical attributes. Demonstrating semiconducting behavior, the electronic nature reveals a band gap of 1.241 eV. The density of states (DOS) illustration validates the semiconductor electronic character, and the calculated magnetic moment, determined through up-down spin DOS, is 3.06 μB/f.u. The Poisson’s ratio value reflects the dominance of ionic bonding in Gd2O3, a finding corroborated by bond population analysis. Impressively, the tetragonal Gd2O3 displays elevated lattice thermal conductivity value in comparison to its cubic, monoclinic, and hexagonal counterparts. Furthermore, the determined melting point registers at 1709.31 K. In the realm of optics, an analysis based on frequency dependence reveals that tetragonal Gd2O3 holds promise as a candidate for optoelectronic applications, particularly in the ultraviolet (UV) energy range.

Hydrogen is a promising clean energy source to address the energy issue as well as the environmental and health risks of current energy sources. Metal hydrides have demonstrated significant potential for storing hydrogen. The perovskite hydrides AMgH 3 (A = Be, Ca) have demonstrated potential for hydrogen storage applications due to their impressive gravimetric hydrogen density of 8.32 and 4.49 wt% for BeMgH 3 and CaMgH 3 , respectively. The calculated results indicate that AMgH 3 (A = Be, Ca) perovskite hydrides exhibit metallic character. The AMgH 3 (A = Be, Ca) compounds mostly absorb quanta of energy in the IR range, but they also exhibit high absorption in the UV region. The formation enthalpies of these hydrides have been found to be negative, indicating that they are thermodynamically stable. Furthermore, it has been established that these perovskite hydrides are mechanically stable as they fulfil Born stability criteria. [Display omitted] • Hydrogen storage properties of AMgH 3 (A = Be, Ca) are investigated using DFT approach. • AMgH 3 (A = Be, Ca) show metallic character as their energy bandgap value is 0 eV. • They show remarkable gravimetric H-densities of 8.32 and 4.49 wt%. • AMgH 3 (A = Be, Ca) perovskite hydrides exhibit thermodynamic and mechanical stability. [ABSTRACT FROM AUTHOR]

This paper will focus on the comparative study of the structural, electronic, magnetic, optical, and thermoelectric properties of the two Heusler systems Ag2TiGa and Ag2VGa in the inverse L21 Hg2CuTi structure. Using the density functional theory‐based wien2k code, which implements the computational methods used in this study, namely GGA, GGA‐mBJ, GGA + U, and GGA + SOC (spin‐orbit coupling). The band structures show that all two structures studied are metallic. The spin density of states of Ag2VGa has evident spin splitting near the Fermi level, and the total magnetic moment of the Ag2VGa structure is 2.19 μB, which indicates that Ag2VGa is magnetic. The full‐Heusler Ag2VGa material can be used as spintronic materials due to their high spin polarization (about 50%). While Ag2TiGa has low polarization so it is bad electronically, but better thermoelectrically than Ag2VGa. So, the full‐Heusler Ag2TiGa material may also be considered as a potential candidate for thermoelectric applications at room temperature. Studies of the two new Heusler alloys may provide a theoretical reference for subsequent theoretical research and experimental synthesis of Ag‐based Heusler alloys. [ABSTRACT FROM AUTHOR]

In this report, we have investigated the CsMgCl3 compound with the help of the WIEN2K software package. The structural and electronic properties are performed using the full potential augmented plane wave (FP-LAPW) method with the generalised gradient approximation (GGA) approximation as exchange correlation potentials. We used the Birch-Murnaghan equation (BME) to find the structural properties of the material. These include the lattice parameter, the bulk modulus, the first derivative of the bulk modulus, the minimum energy, and the volume. The structural properties match up with the experimental data. Electronic properties in terms of the band structure (BS) and total and partial density of state (T-DOS and P-DOS) profiles of CsMgCl3 using GGA potentials exhibit an indirect wide energy band gap of 5.35 eV. All these properties show that the CsMgCl compound is used as a perovskite in solar cells. [ABSTRACT FROM AUTHOR]

In this study, Tin monosulfide SnS semiconductor absorbers was deposited by chemical spray pyrolysis route on the glass substrate. We examined the impact of substrate temperature on the structural, morphological, linear optical and electrical characteristics of SnS absorber at many substrate temperatures such as 50 °C, 375 °C and 400 °C. The SnS films have been analysed by diverse techniques like X-ray diffraction, Raman spectroscopy, Scanning electron microscopy and UV-Vis spectrophotometer. The X-ray diffraction (XRD) spectra revealed that the SnS crystallize in the orthorhombic crystal system with the apparition of the preferential crystallographic direction oriented along (111) planes. The SEM micrographs indicate a great uniformity and granular morphological surface of SnS films. Linear optical constants such as energy gap (Eg), coefficient of extinction (k), index of refraction (n), optical conductivity (σopt), as well as the electrical properties confirm the suitable application of SnS thin films as absorber layer in the optoelectronic device applications. Additionally, we have applied the density functional theory DFT and GGA generalized gradient approximation to study the electronic characteristics; as a result of the electronic band structure the SnS absorber has a suitable energy gap. [ABSTRACT FROM AUTHOR]

Two-dimensional monolayers such as scandium oxyhalides are future compounds for prospective optoelectronics, quantum information, and quantum technologies. These two-dimensional materials have attracted much attention for fundamental and applied research due to their outstanding electronic and optical properties. In this framework, we investigate the electronic and optical properties of two-dimensional ScOX (F, Cl, Br) compounds scandium-based materials employing density functional theory calculations. Our two-dimensional single-layer structures are dynamically stable, as evidenced by the phonon dispersion curves, which showed no unstable phonon modes. The TDOSs and BS calculations show that these 2D sheets are wide-band-gap semiconductors. Our spin-up and spin-down computations demonstrate that our monolayers are non-magnetic compounds. The imaginary part of the dielectric function of these two-dimensional materials disappears at around 30.00 eV, which is the energy dissipation function. Our compounds appear transparent once the incident light’s frequency surpasses the plasma frequency (30.00 eV). The importance of absorption coefficient and gap energy suggests that these materials will be an effective compounds for optoelectronic applications.

The structural and electronic characteristics of Cs2InSbCl6 were investigated using first principle density functional theory (DFT) within local density approximation (LDA) and generalized gradient approximation (GGA) as implemented in the Quantum ESPRESSO package. A supercell with 40 atoms was used in carrying out the calculations, using the optimized lattice parameters of the Cs2InSbCl6 (a = b = c =11.342 Ǻ). The findings revealed that Cs2InSbCl6 is a direct band gap material with gaps of 0.74 eV and 0.99 eV for LDA/PZ and GGA/PBE respectively, in which the GGA/PBE gap shows consistency within the literature range. The calculated densities of states highlight the contributions of the constituent atoms within the valence and the conduction bands.

This study delves into the realm of photocatalysis, seeking to enhance our comprehension by conducting a thorough examination of the electronic structure, structural geometry, and optical properties exhibited by a selection of silver-based compounds. The materials under scrutiny in this investigation include Ag3PO4, Ag2CO3, and Ag3VO4. The investigation commenced with an analysis of five DFT functionals - GGA with PBE, GGA with RPBE, GGA with PBEsol, GGA with PW91, and GGA with WC–to preliminarily evaluate the electronic band structure and structural geometry of these predicted crystals. The principal aim revolved around the elucidation of the band structures characterizing these selected crystalline materials, employing a suite of five distinct Generalized Gradient Approximation (GGA) functionals, as previously elucidated. Notably, the band gap value determined for Ag2CO3 was established at 0.485 eV when employing the GGA-PBE functional, a result that exhibited an exceptional proximity to the reference value of 0.470 eV. As a corollary, the GGA-PBE method emerged as the preeminent and most precise computational technique among those considered for the examination of these specific compounds. Secondly, the Density of States (DOS) and Partial Density of States (PDOS), evaluated for emphasizing the atomic orbital contributions. Furthermore, six optical properties - absorption, reflection, refractive index, conductivity, dielectric function, and loss function - were dissected to offer deeper optical insights with comparative exploration. Last, crystals' mobility by calculating the effective mass of electrons and holes, as well as the reduced effective electron mass examined for predicting electronic transition to conveying photo catalytic behavior of crystals. However, the band gap of Ag2CO3 is much lower than other crystals (Ag3PO4, Ag3VO4 (Tetragonal) and Ag3VO4) even it is similar trend for effective masses for electrons (0.4174) and holes (0.85985) as well as reduced effective masses (0.8112). However, Ag2CO3 is more effective photo catalytic agent, meaning carbonate (--CO3) group acts more convenient with silver metal as photo catalytic activities.

Cu-based chalcogenide materials have attracted a great deal of attention due to their promising optoelectronic properties. The density functional theory (DFT) framework is used in order to estimate the optical and electronic properties of XCu2GeQ4 (X = Ba, Sr and Q = S, Se). We report the optical and electronic properties of Cu-based chalcogenides in this study, which have narrow and direct bandgap materials. The calculated energy bandgap of quaternary chalcogenide materials decreases in the following sequence: SrCu2GeS4 (0.697 eV), BaCu2GeS4 (0.667 eV), BaCu2GeSe4 (0.378 eV), and SrCu2GeSe4 (0.195 eV). This reduction in energy bandgaps shows significant effect of changing dopants on electronic and consequently optical properties of XCu2GeQ4 (X = Ba, Sr and Q = S, Se). The optical characteristics of these materials are investigated in order to explore their potential for optoelectronic applications. However, other materials are emerging as contenders for solar cells, which operate from UV to infrared regions. Initially in infrared region, we can note a redshift in the maximum absorption of incident photons from ε 2 (ω) plots in the following sequence: BaCu2GeS4 (1.52 eV), SrCu2GeS4 (1.50 eV), BaCu2GeSe4 (1.30 eV), and SrCu2GeSe4 (0.93 eV). The approximated values of reflectivity, R(ω) are plotted against incident photon energy from 0 to14 eV. Thus, the reflectivity is approximately below 50% before E ≈ 12.0 eV and then increased to 70% reflection at ~ 13.0 eV. Based on calculated thermoelectric properties, these chalcogenides are promising thermoelectric materials. The ZT values of XCu2GeQ4 (X = Ba, Sr and Q = S, Se) decreased in the following sequence: SrCu2GeSe4 (2.6), BaCu2GeSe4 (1.85), SrCu2GeS4 (1.01) and BaCu2GeS4 (0.94). Hence, we believe our findings propose promising materials for anti-reflecting coating layers in optoelectronic technology. [ABSTRACT FROM AUTHOR]

We are studied the electronic and magnetic properties of the A-site ordered perovskite CaCo3V4O12 within the density-functional theory using the generalized gradient approximation (GGA) with the consideration of strong Coulomb correlations (GGA + U) in the framework of the fully relativistic spinpolarized Dirac linear muffin-tin orbital method of band-structure calculation. The x-ray absorption spectra and x-ray magnetic circular dichroism at the Ca, Co, and V K-edges are investigated theoretically. The effect of the electric quadrupole E2 transitions and magnetic dipole M1 transitions are analysed. The calculated results are in good agreement with experimental data. [ABSTRACT FROM AUTHOR]

MgF2 is a compound that is transparent to the full spectrum from UV to IR and is a good candidate for UV applications. Structural, optical, electronic and elastic properties of MgF2 compounds in the three phases in which our materials may crystallize have been studied using the linearized full potential self-consistent plane wave (FLAPW) method with Wu-Cohen generalized gradient approximation (WC-GGA) and modified Becke–Johnson potentials. The most remarkable is the similarity between the properties of the three phases at all levels (gaps, optical constants). A comparison of our outcomes with the literature indicates great agreement. [ABSTRACT FROM AUTHOR]

Our TiO2 thin films were elaborated using spray pyrolysis technique. The spray solutions were prepared by two titanium precursors: titanium (IV) propoxide and titanium chloride. The elaborated thin films were analyzed with different characterization techniques such as X‐ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM), and UV–visible spectroscopy. These characterizations showed that the change of precursors from titanium chloride to titanium propoxide has a significant impact on all TiO2 properties. The structural characterizations showed the formation of anatase TiO2 and the crystallization improvement when the precursor changed from titanium chloride to titanium (IV) propoxide, which proves the superiority of our TiO2 thin layers made without any type of annealing in comparison with other previous studies. The SEM images showed an improvement of the surface quality of the TiO2 thin layers with the change of TiO2 precursors' solution. The obtained optical properties confirmed the semiconducting properties of TiO2 prepared by titanium propoxide with a large band gap equal to 3.28 eV and shifted to 3.18 eV. The refractive index increases from ~1.75 to ~2.14, while the porosity decreases. To confirm the experimental results, the Wien2K code, founded on the full‐potential linearized augmented plane wave (FP‐LAPW), has been used. The theoretical study has been done by applying the generalized gradient approximation (GGA), the modified Beck‐Johnson (MBJ) exchange potential, and the local spin density approximation + Hubbard's parameter U (LSDA + U). The theoretical results varied with the variation of approximations. The obtained properties were improved with LSDA + U and acquired the real values of Eg, n, and k for anatase TiO2 (like Eg = 3.214 eV). The obtained experimental and theoretical results could be considered superposable or better than other ones recently published. [ABSTRACT FROM AUTHOR]

The half-metallic calculations of new variant perovskites Li2CrO6 and Li2CuO6 were carried out by using WIEN2k computational code. First, the ferromagnetic (FM) and non-magnetic (NM) phases were compared, and FM phases were obtained energetically more stable. The equilibrium lattice constants were obtained as 7.63 Å and 7.66 Å for Li2CrO6 and Li2CuO6, respectively. Second, the electronic calculations were performed, and the semiconduction properties were seen in spin-up states while spin-down states showed metallic nature. The band gaps were obtained as 1.806 eV and 1.177 eV for Li2CrO6 and Li2CuO6, respectively. Since variant perovskites Li2CrO6 and Li2CuO6 showed 100% spin polarizations, these were obtained as true half-metallic ferromagnetic materials. Then the total magnetic moments were obtained as 4.00 μB/f.u., 5.00 μB/f.u. When both the electronic and magnetic properties of the compounds are examined, the variant perovskites Li2CrO6 and Li2CuO6 are suitable materials for spintronics applications. [ABSTRACT FROM AUTHOR]

Theoretical studies of the role of exchange correlation effects in the prediction of the half-metallic properties of ferrimagnetic Mn2VAl and Mn2VSi Heusler alloys, which are of interest in spintronics, are presented. Electronic, magnetic, and structural properties are studied within the framework of density functional theory. It is shown that the correction for additional correlation effects makes it possible to reveal two states, which are close to each other in energy, but have different magnetic moments. The state with a low magnetization demonstrates a half-metallic character with 100% spin polarization, whereas the state with a high magnetization has a metallic character. [ABSTRACT FROM AUTHOR]

We present the use of gentamicin (GENTA) and sulfamethoxazole (SULFA) for carbon steel corrosion protection in HCl solutions using weight loss, electrochemical impedance spectroscopy, potentiodynamic polarization techniques, molecular dynamic simulations plane-wave density functional theory (PWDFT) and the generalized gradient approximation, (GGA). The surface morphologies were examined using scanning electron microscopy (SEM). The potentiodynamic polarization test showed that GENTA and SULFA are mixed-type inhibitors with maximum achievable inhibition efficiency of 90% and 80%, respectively at 500 ppm. SEM analysis further confirmed the inhibitory action of GENTA and SULFA on carbon steel. Molecular simulations reveal two stable adsorption configurations on the Fe (110) surface for GENTA and SULFA which were identified after geometry optimization using PWDFT and the GGA. The presence of the delocalized п-electrons of the aromatic rings provided extra stability to the configurations with flat adsorption orientations on the Fe (100) surface. The inhibitor adsorption energies and electronic properties correlate well with the experimental results. [ABSTRACT FROM AUTHOR]

In this study we have investigated the robust phase stability, elasto-mechanical, thermophysical and magnetic response of KVSb half Heusler compound by implementing density functional theory (DFT) models in WIEN2k simulation package. The dynamic phase stability is computed in phase type I, II & III phase configurations by optimising their energy. It is observed that given compound is more stable in spin-polarized state of phase type-III. To explore the electronic band structure, we apply the generalised gradient approximation along with Hubbard potential U. The electronic band profile of the Heusler alloy display a half-metallic nature. Moreover, the calculated second-order elastic parameters divulge the brittle nature. To understand the thermodynamical and thermoelectric stability of the alloy at various temperature and pressures ranges Quasi-Harmonic Debye model is executed successfully. The computed value of magnetic moment (MM) found in good agreement with Slater-Pauling rule. Our findings confirms that the predicted half Heusler alloy can be used in various spintronics and thermoelectric applications. [ABSTRACT FROM AUTHOR]

Formation of transport vesicles requires the coordinate activity of the coating machinery that selects cargo into the nascent vesicle and the membrane bending machinery that imparts curvature to the forming bud. Vesicle coating at the trans -Golgi Network (TGN) involves AP1, GGA2 and clathrin, which are recruited to membranes by activated ARF GTPases. The ARF activation at the TGN is mediated by the BIG1 and BIG2 guanine nucleotide exchange factors (GEFs). Membrane deformation at the TGN has been shown to be mediated by lipid flippases, including ATP8A1, that moves phospholipids from the inner to the outer leaflet of the TGN membrane. We probed a possible coupling between the coating and deformation machineries by testing for an interaction between BIG1, BIG2 and ATP8A1, and by assessing whether such an interaction may influence coating efficiency. Herein, we document that BIG1 and BIG2 co-localize with ATP8A1 in both, static and highly mobile TGN elements, and that BIG1 and BIG2 bind ATP8A1. We show that the interaction involves the catalytic Sec7 domain of the GEFs and the cytosolic C -terminal tail of ATP8A1. Moreover, we report that the expression of ATP8A1, but not ATP8A1 lacking the GEF-binding cytosolic tail, increases the generation of activated ARFs at the TGN and increases the selective recruitment of AP1, GGA2 and clathrin to TGN membranes. This occurs without increasing BIG1 or BIG2 levels at the TGN, suggesting that the binding of the ATP8A1 flippase tail to the Sec7 domain of BIG1/BIG2 increases their catalytic activity. Our results support a model in which a flippase component of the deformation machinery impacts the activity of the GEF component of the coating machinery. [Display omitted] • The lipid flippase ATP8A1 interacts with the Guanine Nucleotide Exchange Factors BIG1/BIG2 at the trans-Golgi network (TGN) in mammalian cells. • ATP8A1 and BIG1/BIG2 interaction stimulates activated ARFs at the TGN, recruiting AP1, GGA2, and clathrin. • ATP8A1 co-localizes with BIG1/BIG2 in static and mobile TGN elements, linking membrane deformation with coating processes. [ABSTRACT FROM AUTHOR]

The influence of the exchange-correlation functional on the crystal fundamental property calculation is shown. CrGeTe3, compound with transition metals, was used for the simulation of structural and electronic properties. The calculations were carried out using such functional classes as LDA and GGA. It has been shown that LDA exhibits 0.4 % and 5.2 % overestimations of the lattice constants for a and c, respectively. GGA (OR) overestimates a by 0.58 % and underestimates c by 4 %. The influence of the Hubbard correction on the band gap was also investigated. If Ueff is applied to the d-electrons, then the band gap will decrease. This is due to the hybridization of the p-electrons of the chalcogen and the d-electrons of the transition metal. Thus, GGA demonstrates better agreement with the experiment. The convergence of the calculation of the total energy with a change in the k-points and the cutoff energy were also investigated.

The changes in the magnetic and half-metallic characters of the structures formed by the doping of Ag, Cd, Y, Zr, and Nb atoms at the ratios of x = 0.25 and 0.125 to WSn alloy were investigated. While the spin-up states of all alloys showed metallic character, energy band gaps were observed in the spin-down states, except YSn alloy. Of the 10 structures, 84.10% spin polarization was obtained only in the Zr0.25W0.75Sn alloy, and the spin polarizations were 100% in all remaining alloys. Band calculations were made with both GGA and GGA + mBJ methods. When the GGA + mBJ method was used, an increase in band gaps was observed in proportion to the increase in Fermi energy levels. In addition, the obtained 3, 4, 5, 6, 7 μB/f.u. magnetic moments for M0.25(M = Ag, Cd, Y, Zr, Nb)W0.75Sn alloys, respectively, and the calculated magnetic moment per unit formula of 5.5, 6, 6.5, 7, 7.5 μB/f.u. for M0.125(M = Ag, Cd, Y, Zr)W0.875Sn alloys support their fields that can be used in spintronic applications. The magnetic moment values obtained with GGA-U (U = 1, 2, 3, 4 eV) calculations showed that while the magnetic moment values of Zr0.25W0.75Sn and Nb0.25W0.75Sn alloys were preserved, they directly increased the magnetic moments of some alloys. These high ratios of polarization, band gaps, and magnetic moments make all alloys ideal materials for use in spintronic applications. [ABSTRACT FROM AUTHOR]

Summary: The electronic, optical, magnetic, and thermoelectrical properties of both, the monoclinic (α‐form) and the orthorhombic (β‐form) phases of sodium manganese (II) arsenate NaMnAsO4 cluster are investigated comprehensively by the first‐principle calculations based on the Density Functional Theory. The full‐potential linearized augmented plane waves method within the generalized gradient approximation (GGA) and GGA + U approaches have been performed by the Wien2k software. Thermodynamic stability is confirmed by means of formation energy (ΔHf). The spin‐polarization is included in the calculations to study the electronic and magnetic properties. The indirect bandgaps are observed for the monoclinic phase, then the direct bandgaps are reported at Γ‐symmetry point for the orthorhombic phase. The density of state, besides the band structure calculation, revealed that the studied material can be identified as a ferromagnetic semiconductor at low temperature with an optical bandgap energy of 1.35 and 0.83 eV for monoclinic and orthorhombic phases with GGA approach, as well as 1.27 and 1.59 eV with GGA + U approach, respectively. The refractive index range is 1.5 to 2.4 along with a wide absorption band in the UV region, which makes this material outstanding for optoelectronic devices. The thermoelectric properties for both structures have also been investigated using the BoltzTraP package. The obtained electrical conductivity, as well as the figure of merit, are found to be important for thermoelectrical devices. This suggests that NaMnAsO4 could pave the way to further experimental research on optoelectronic‐thermoelectric applications. [ABSTRACT FROM AUTHOR]

Background: Familial juvenile hyperuricemic nephropathy (FJHN) is an autosomal dominant disorder caused by mutations in UMOD. Here we studied effects of genetic expression and pharmacological induction of Hsp70 on the UMOD mutants C112Y and C217G. Methods: We expressed wild type (WT), C112Y and C217G in HEK293 cells and studied their maturation and cellular damage using western blot and flow cytometry. Results: Expression of C112Y or C217G increased pro-apoptotic proteins, decreased anti-apoptotic proteins, and induced cellular apoptosis as examined by annexin V staining and flow cytometry. Overexpression of Hsp70 or administration of an Hsp70 inducer geranylgeranylacetone (GGA) promoted maturation of the mutant proteins, increased their secreted forms, normalized the levels of pro- and anti-apoptotic proteins and suppressed apoptosis. Conclusion: These findings indicated that Hsp70 enhanced maturation of C112Y and C217G and reduced cellular apoptosis, suggesting that Hsp70 induction might be of a therapeutic value for treatment of FJHN. [ABSTRACT FROM AUTHOR]

Solid-state physics is the study of the fundamental properties of solid, crystalline or amorphous materials, energy bands (band structures or electronic band structures) of solids, it explains the range of energy levels that electrons may have inside it, and the range of energy levels that they may not have. In general, these electrons have the possibility to take that energy values within certain ranges, which are separated by forbidden energy bands (named band gaps). This approach leads to the discussion of band theory. Band theory derives these bands and band gaps by studying the authorized quantum mechanical wave functions for an electron in a large, periodic lattice of atoms or molecules. The band theory has been successfully utilized to describe many physical properties of solids and forms the basis of comprehension of all solid-state devices (transistors, diodes, solar cells, etc.). In this work, the electronic proprieties (band structures, partial and total density of states (DOS), charge density) of α-Al2O3 are calculated using ADF-BAND program. The calculations are based on the density functional theory (DFT), pseudopotential approximation and Slater Type Orbital (STO) as basic functions, with local density approximation (LDA) and generalized gradient approximation (GGA). α-Al2O3 is a high-k dielectric and has excellent properties (dielectric constant k ≈ 10 and direct band gap Eg ≈ 8.8 eV). Al2O3, HfO2 and ZrO2 are the promising high-k dielectric candidates to replace SiO2 as the gate dielectric material in MOS transistors. [ABSTRACT FROM AUTHOR]

The structural of MgB2 such as lattice constant, volume modulus, volume modulus derivative and compressibility of different degrees have been calculated. The calculations have been performed using a Full Potential-Linearized Augmented Plane Wave (FP-LAPW) method in the framework of Density Functional Theory (DFT) with various Approximation. The results show that the linear compressibility in direction of c is about twice the compressibility in direction of a. In addition, the electronic properties of the compound, including the structure of the energy bands, the density of the states, and the types of bonds in the MgB2 Superconductivity have been studied. The results of a double degeneracy above the Fermi level show that it plays an important role in the superconducting property. According to energy bands, it has been determined that the lattice parameters have a large effect on the s band of boron atoms. The results predict that the constant increase of the lattice along the c-axis has an increase in the density of states at the Fermi level. The results express this fact that the calculation using by GGA has the better agreements with the other theoretical and experimental approximations.

Since the last decade, the half-Heusler (HH) compounds have taken an important place in the field of the condensed matter physics research. The multiplicity of substitutions of transition elements at the crystallographic sites X, Y and (III-V) elements at the Z sites, gives to the HH alloys a multitudes of remarkable properties. In the present study, we examined the structural, electronic and thermoelectric properties of ZrCoBi0.75Z0.25 (Z = P, As, Sb) using density functional theory (DFT). The computations have been done parallel to the full potential linearized augmented plane wave (FP-LAPW) method as implemented in the WIEN2k code. The thermoelectrically properties were predicted via the semi-classical Boltzmann transport theory, as performed in Boltztrap code. The obtained results for the band structure and densities of states confirm the semiconductor (SC) nature of the three compounds with an indirect band gap, which is around 1eV. The main thermoelectric parameters such as Seebeck coefficient, thermal conductivity, electrical conductivity and figure of merit were estimated for temperatures ranging from zero to 1200K. The positive values of Seebeck coefficient (S) confirm that the ZrCoBi0.75Z0.25 (x = 0 and 0.25) are a p-type SC. At the ambient temperature, ZrCoBi0.75P0.25 exhibit the large S value of 289 µV/K, which constitutes an improvement of 22% than the undoped ZrCoBi, and show also a reduction of 54% in thermal conductivity (κ/τ). The undoped ZrCoBi has the lowest ZT value at all temperatures and by substituting bismuth atom by one of the sp elements (P, As, Sb), a simultaneous improvement in κ/τ and S have led to maximum figure of merit (ZT) values of about 0.84 obtained at 1200 K for the three-doped compounds.

We present a theoretical comprehensive study which predicts and examines the outcomes of the structural, elastic, electronic, and optical properties of berylliumbased fluoroperovskite BeMF3 (M = Ti and V) compounds which was performed based on DFT (Density Functional Theory). The theoretical computation was done through the simulation package of WIEN2k, in which the implemented method of Full-Potential Linearized Augmented Plane Wave (FP-LAPW) was used. For the treatment of exchange correlation potential, the Generalized Gradient Approximation (GGA) was used for structural and elastic properties while the Modified Becke-Johnson (mBJ) exchange potential was used for a better understanding of the electronic and optical properties. Structural optimization was done with the Birch-Murnaghan equation of state, for the outcomes of fundamental optimized lattice parameters. The optimized 4.0833 Å and 4.0112 Å lattice constants were found for the BeTiF3 and BeVF3, respectively, and we found that both these compounds were structurally stable. For the computation of the elastic constants (ECs) of these crystals the IRelast package was used. Elastically these compounds were found to be mechanically stable because they satisfy the stability criteria, and are anisotropic and ductile in nature. Both the compounds of interest are metallic in nature and have overlapping valence and conduction bands. The TDOS and PDOS (total and partial density of state) plots were used to infer the relevance of the states contributed by each constituent element to the valence and conduction bands. Important optical properties, namely the dielectric function ε(ω), optical conductivity σ(ω), reflectivity R(ω), refractive index η(ω), and extinction coefficient k(ω) were examined and evaluated in a wide energy range (0-40 eV). Both the compounds were found to possess high optical conductivity in the low energy range, and because of these properties both the materials can be deemed to be likely to be of value in many modern electronic devices. To the best of our knowledge, this is the first precise theoretical insight into the some of the physical properties of BeMF3 (M = Ti and V) compounds. These properties are still to be verified experimentally. [ABSTRACT FROM AUTHOR]

In Internet of Things (IoT) business applications, healthcare records and medical web service management have emerging technologies tremendous amount of data in daily transactions. The cloud service providers have attracted the attention of a huge number of user requests based on different Quality of Service (QoS) factors. The data gained researchers attention to predict user behavior through the production of IoT applications. Artificial Intelligence (AI)-based techniques have a great impact on analyzing and detection of web service segmentation and user behavior in selecting and allocating online services and online stores with wireless communications and smart devices. This research improves the Redundancy, Frequency, and Maintenance value (RFM) model to evaluate healthcare records using a hybrid Grouping Genetic Algorithm (GGA) and Density-based Spatial Clustering of Applications with Noise (DBSCAN) algorithms. In this hybrid method, using the GGA algorithm, the features selection is applied to find the optimal features for healthcare records of customer segmentation. After that, by applying the RFM model on the data output of the genetic algorithm, the data are clustered. Finally, by applying the DBSCAN algorithm, the most suitable case for clustering will be selected. The simulation results show that the accuracy of the genetic algorithm is 97% and the final clustering accuracy is 92%. [ABSTRACT FROM AUTHOR]

In order to probe the bandgap engineering to tune optical properties in YAuPb1−xSix (x = 0, 0.25, 0.50, 0.75 and 1) alloys, we used all-electron full-potential linearized augmented plane wave (FP-LAPW+lo) method within the framework of the density functional theory. The optimized structural parameters were in good agreement with other theoretical and experimental results. The calculated results of elastic constant satisfy the condition for mechanical stability at each composition for cubic symmetry. In addition, the study of elastic parameters is summarized for the calculation bulk modulus, Young's modulus, shear modulus, Kleinman parameters, Poisson's ratio and Lame's co-efficient. To predict the brittle (ductile) nature of this composition, the Cauchy pressure, Poisson's ratio, and B/G ratio were also calculated. Using modified Becke and Johnson GGA, the bandgap values of each composition were computed precisely. Further, it was observed that for 0.25 < x < 0.75, the bandgap structure revealed a direct bandgap configuration. In order to analyze the electronic structure of each composition, the total and partial densities of states have been investigated in detail. Furthermore, the investigation of optical parameters in terms of dielectric functions revealed the potential of these alloys for optoelectronic devices. [ABSTRACT FROM AUTHOR]

The density functional theory (DFT) is used to study the structural, electronic, magnetic properties of Heusler Alloy compounds PdCoMnAl. The calculations are performed via FP-LAPW computational approaches as part of the generalized gradient approximation GGA and modified Becke--Johnson TB-mBJ for exchange-correlation potential. The prediction of the structure of the energy bands and of the densities of states shows a strong hybridization between the states d of the atoms of the transition metals of high valence (Pd) and the states d of the atoms of the transition metal of low valence (Mn) and (Co), which generates a half-metallic gap. In addition, the densities of total and partial states (PDOS) and the results of magnetic spin moments reveal that this compound is stable and ideal half-metallic ferromagnetic. The effects of the unit cell volume on the half-metallic and magnetic properties are crucial. It is interesting to note that our results of the total magnetic moment for PdCoMnAl equal to 5 µB per unit cell, nicely follow the rule µtot = Zt-18. [ABSTRACT FROM AUTHOR]

By employing the first principles method within the generalized gradient approximation for the exchange and correlation potential, the electronic, optical and magnetic properties of pure and Fe-doped zinc-blende ZnSe are investigated. According to the obtained band structure, density of state and optical spectrum the electronic origin of the maxima in the optical spectrum has been observed. The optical spectrum peak is generated mainly from the charge transfer between the Se(4 p) and Zn(3 p) states. Our results reveal that the strong spin polarization of the 3 d states of the Fe atoms is the origin of antiferromagnetism in Zn 1 − x Fe x Se. A decrease in the concentration of iron atoms in the supercell does not affect the stability of the AFM phase. [ABSTRACT FROM AUTHOR]

This study aims to describe the social structure of the GGA novel based on the perspective of the Mataram ruler. This research is a qualitative descriptive study with a research strategy using content analysis with a genetic structuralism approach. Data and data sources in this study are in the form of words, phrases, sentences, and paragraphs contained in the GGA novel by RH Widada. Other than that the data will be supported by the transcript results of the author’s interview. Data collection techniques with library techniques, refer to and record. Data validation techniques with data triangulation, researchers, and methodology. Data analysis in this study used the interactive model analysis Miles and Huberman. The result showed that the figure of Javanese woman was seen as a figure that could be taken to be a concubine or consort in accordance or consort in accordance with the wishes of the king regardless of marital status or not, a female figure could also be possessed by the king by searching/hunting throughout the country, a cruel punishment to women, the use of women as initiators kenya formidable king’s bodyguards and women symbol of the king’s keprabon revelation.

The local lattice distortion (LLD) effects in the disordered alloys with the large atomic-size misfit between the constituent elements are well known to be essential for reproducing theoretically the observed phase diagrams including order-disorder critical temperatures, although the theoretical approach from first principles remains a long-standing problem. We propose the Kanzaki model combined with the full potential (FP) Korringa-Kohn-Rostoker (KKR) Green's function method, as an approximation for the direct FPKKR calculations, which is based on the harmonic approximation of the atomic displacements and enables us to study the long-ranged LLD effects in the disordered alloys. We first show that the present Kanzaki model may reproduce very accurately the LLD energies obtained by the direct FPKKR calculations with the restriction on the displacement of only the 1st-nearest neighboring atoms around a single impurity X in Al, although the discrepancy increases with the atomic-size misfit between Al and X atoms. Second we clarify the fundamental features of the LLD energies (over -10000 atoms) around a single impurity X (= H-Sn) in Al, corresponding to the 1-body part in our real space cluster expansion for the LLD energy in the Al-rich AlX disordered alloy; the 1-body LLD energy becomes larger and more long-ranged with the atomic-size misfit between Al and X elements and also with the sp-d interaction of Al-X (X = d element). [ABSTRACT FROM AUTHOR]

[Display omitted] • First principle investigations of OsS 2 in pyrite type structure. • The semiconducting nature with a narrow band gap is expected. • The doping of Os site with Fe and Ru improves the band gap. • Enhancement of optical properties like absorption coefficient, reflectivity, refractive index, and optical conductivity when doped.. In the present manuscript, we report a systematic investigation of the structural, electronic, and optical properties including the elastic behaviour of erlichmanite (OsS 2), using FP-LAPW method. The effect of exchange correlation functional when treated with GGA, this ductile semiconductor shows an electronic band gap of 0.34 eV that has been enhanced to 0.75 eV when mBJ potential is employed. The band gap of OsS 2 further widens when Os site is doped with Fe/Ru with its highest value of 1.83 eV when 75 % of Os is replaced with Fe. The addition of dopant also improves the refractive index of the sample with highest amplitude when 75 % Fe doping and the optical absorption coefficient reaches its highest limit of 8.7 × 105 cm−1 and 9.1 × 106 cm−1 in the visible energy range for 75 % Fe and Ru doping, respectively. [ABSTRACT FROM AUTHOR]

Two-dimensional monolayers such as scandium oxyhalides are future compounds for prospective optoelectronics, quantum information, and quantum technologies. These two-dimensional materials have attracted much attention for fundamental and applied research due to their outstanding electronic and optical properties. In this framework, we investigate the electronic and optical properties of two-dimensional ScOX (F, Cl, Br) compounds scandium-based materials employing density functional theory calculations. Our two-dimensional single-layer structures are dynamically stable, as evidenced by the phonon dispersion curves, which showed no unstable phonon modes. The TDOSs and BS calculations show that these 2D sheets are wide-band-gap semiconductors. Our spin-up and spin-down computations demonstrate that our monolayers are non-magnetic compounds. The imaginary part of the dielectric function of these two-dimensional materials disappears at around 30.00 eV, which is the energy dissipation function. Our compounds appear transparent once the incident light's frequency surpasses the plasma frequency (30.00 eV). The importance of absorption coefficient and gap energy suggests that these materials will be an effective compounds for optoelectronic applications. • Electronic and optical properties of ScOX (F, Cl, Br) two-dimensional scandium based-material are investigated. • Our 2D single-layer structures are dynamically stable. • The TDOSs and BS calculations show that these 2D sheets are wide-band-gap semiconductors. • Our spin-up and spin-down computations demonstrate that our monolayers are non-magnetic compounds. • Our compounds appear transparent once the incident light's frequency surpasses the plasma frequency (30.00 eV). [ABSTRACT FROM AUTHOR]

This article asserts the importance of public participation in local government, through social action research, in order to achieve good governance. We examine how bad local governance negatively impacts the socio-economic development trajectory of communities. Based on fieldwork conducted in the Eastern Cape province of South Africa, this article illustrates the transformative role participatory processes and good governance played as peacebuilding mechanisms to achieve positive peace in the Mbizana local municipality. The municipality’s geography spans from deep rural areas to the urban central business district (CBD). A mixed qual-quant methodology with a phased rollout was applied to engage the local government and communities involved, and target with precision the lived reality of the residents. The findings of the study point to the transformative nature of the local participatory processes that entailed building confidence between the municipal authorities, the NGO Good Governance Africa (GGA) and the Mbizana community, and new ideas on how to facilitate public participation. Our conclusion is that civil society organisations should build trust with local authorities in communities for public participation interventions to be successful. This outlook differs to perceiving local authorities as a threat or barrier to direct interventions. The combination of participatory processes and good governance restored the community’s confidence in the municipality through shared governance information and capacity building. This hybrid approach can be replicated and applied to promote sustainable peace in communities that face similar challenges.

Ab initio calculations were performed to investigate the structural and electronic properties of bulk CdTe using various exchange–correlation (XC) functionals available. Among the selected XC functionals include the local density approximation (LDA), generalized gradient approximation (GGA), meta-generalized gradient approximation (MGGA) (using the linear combination of atomic orbitals basis scheme) and Heyd–Scuseria–Ernzerhof-06 (HSE06) (using the plane-wave basis scheme). Further computational studies were performed based on the local density approximation-1/2 (LDA-1/2) and generalized gradient approximation-1/2 (GGA-1/2) self-energy correction schemes to verify their effect on the CdTe band gap in comparison to the other traditional XC functionals. The lattice parameter values obtained using different XC functionals (LDA, GGA and MGGA) were well in agreement with experimental value, with LDA predicting 6.548 Å. This is 1.02% greater than the experimental value of 6.482 Å. The electronic structure of CdTe was calculated for the fixed 6.482 Å lattice parameter of bulk CdTe and resulted in a band gap ranging between 0.68 and 1.56 eV for LDA, GGA, MGGA, and HSE06. The band gap values predicted by the LDA-1/2 and GGA-1/2 corrections were 1.47 eV and 1.50 eV, respectively, and are found to be in good agreement with experimental values. The influence of XC functionals and semi-empirical correction schemes are expected to have important implications on the prediction and understanding of bulk CdTe thin-films found in photovoltaic applications. [ABSTRACT FROM AUTHOR]

The aim of this work is the study of the magnetic, elastic, thermic, and thermoelectric properties of the ternary full-Heusler alloys Ru2VZ (Z = Ge and Sb) in L21 structure, using an ab initio calculation within the linearized augmented plane wave method with a full potential (FP-LAPW) based on the density functional theory (DFT). We computed these properties within the general gradient approximation (GGA). The structural parameters obtained are in favorable agreement with respect to the theoretical values found in the literature. The electronic properties studied have shown that the compounds have a half-metallic behavior. We have also computed the mechanical properties where we found that these full-Heusler compounds are mechanically stable. Furthermore, we have studied the thermal properties by the quasi-harmonic Debye model incorporated in the GIBBS code, which takes into account the lattice vibrations, pressure, and temperature effects on structural parameters. The thermoelectric properties were computed as a function of chemical potential at 300, 600, and 900 K. To our knowledge, the thermodynamic and thermoelectric characteristics have not yet been measured or calculated; hence, our results serve as a prediction for future study. Our obtained results for these quantities make these compounds attractive candidates for materials used in spintronic devices. [ABSTRACT FROM AUTHOR]

In the present paper, the structural, electronic, and linear optical properties of different phases of the gallium nitride (GaN) have been investigated. The zinc blende and wurtzite phases of the GaN have been studied using the full-potential linearized augmented plane wave method (FP-LAPW). In our study, many approximations have been used, such as the local density approximation (LDA), the generalized gradient approximation (GGA), the Engel and Vosko generalized gradient approximation (EV-GGA), and the modified Becke-Johnson (mBJ) potential exchange. As a result, we found a very good agreement with literature experimental results for the energy band gap using the mBJ approximation with a scaling factor of 98% and 80% for the zinc blende and wurtzite phases, respectively. [ABSTRACT FROM AUTHOR]

Structural, electronic, elastic and thermodynamic properties of Ni2LaZ (Z = As, Sb and Bi) Heusler alloys based on rare earth element have been investigated using full-potential linear muffin-tin orbital (FP-LMTO) method within generalized gradient approximation (GGA) in the frame of density functional theory (DFT). By using total energy variations, the independent elastic constants and their pressure dependence have been determined. Also, anisotropic parameter (A), shear modulus (G), Young modulus (E), Poisson's ratio (ν), ratio (B/G) are calculated. Using quasi-harmonic Debye model, thermodynamic properties of Ni2LaZ (Z = As, Sb and Bi) Heusler alloys are investigated in temperature range 0–1200 K and pressure range 0–50 GPa. The temperature and pressure effects on the unit cell volume, bulk modulus (B), heat capacities (Cv) at stable volume, (Cp), Debye temperatures (θD), Gibbs energies (G), thermal expansion coefficients (α) and entropies (S) are determined from non-equilibrium Gibbs functions. This study allows to understand deeply the structural and thermodynamic properties of Ni2LaZ (Z = As, Sb and Bi) Heusler alloys in shortest time and cost-effective. [ABSTRACT FROM AUTHOR]

در این مقاله ساختار الکترونی و ساختار نوارهای انرژی بلور GaAs در فاز بِلِندروی با استفاده از روش امواج تخت بهبودیافتۀ خطی با پتانسیل کامل FP-LAPW در چارچوب نظریۀ تابعی چگالی (DFT) و با تقریب‌های مختلف و استفاده از کد محاسباتی Wien2k انجام شده است. در این روش، برای محاسبۀ پتانسیل تبادل‌ـ‌همبستگی از تقریب‌های LDA و شیب تعمیم‌یافته استفاده شده است. نتایج بیانگر آن است که خصوصیات الکترونی و ساختاریِ محاسبه‌شدۀ این ترکیب از جمله ثابت شبکه و مدول حجمی و تراکم‌پذیری و مشتق مدول حجمی با استفاده از تقریب GGA نسبت به سایر تقریب‌ها سازگاری بهتری با نتایج تجربی و نظری به‌دست‌آمده از روش‌های دیگر دارد.

In this study, we report the electronic structure properties of SmFe2 and HoCo2 binary Laves phase compounds using the density functional theory (DFT) method. We treated the exchange correlation potential with generalized gradient approximation (GGA); in addition, GGA+U (U: Hubbard correction) calculations were applied to describe the correlation effects. At the equilibrium state, the lattice parameter a 0 is found in favorable agreement with the available data. We also treated the magnetic properties of SmFe2 and HoCo2, respectively; it is shown that the magnetic moment values of Sm and Ho atoms are larger than those of Fe and Ho elements. We note that the GGA with Hubbard correction (U) provides the best description of our systems. We also illustrated the band structures and total and partial densities of states (DOS) of the rare earth-4f (Sm and Ho) and transition metals-3d (Fe and Co) orbitals. For both approximations used, the SmFe2 and HoCo2 binary compounds have a metallic character at the Fermi level. This investigation shows the importance of the treatment of correlated electrons for a clear and accurate description of these binary compounds of the Laves phases family. [ABSTRACT FROM AUTHOR]

A simple approach was developed for the rapid and accurate estimation of 5-day biochemical oxygen demand (BOD5) in food processing wastewater. Immobilization of the natural microbial consortium that was collected from an aerobic compartment of a food processing wastewater treatment plant was simply performed by adhesion using a low-cost porous carrier. Pseudomonas aeruginosa, Bacillus cereus, and Streptomyces, whose salt-tolerance and ability to break down organic compounds have been widely reported, were found to be predominant. These microorganisms may cause an enhancement of the bioreactor response in the presence of sodium chloride. Consequently, a modified glucose-glutamic acid (GGA) calibration standard was proposed in which an appropriate amount of NaCl was added; this solution was found to be more effective in terms of accuracy and practicality than both conventional GGA and the synthetic wastewater recipe from the Organisation for Economic Cooperation and Development (OECD). The calibrated self-built packed-bed bioreactor exhibited good precision of 3% or less in predicting BOD5 in influent, which is similar to the performance of the most common commercial biochemical oxygen demand (BOD) bioreactors. There was a statistical agreement between the results obtained from this rapid BOD biosensor and the conventional methods, even when testing treated wastewater samples. [ABSTRACT FROM AUTHOR]