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831.
In this paper, we investigate the behavior of a scalar particle within the Yukawa-like potential in a Gödel-type space-time for any l. The behavior of a spinless particle is analyzed in the presence of a topological defect with analytical solutions to the Klein–Gordon equation. By using the generalized series and Nikiforov-Uvarof (NU) methods, we deduce the energy eigenvalues and eigenfunctions. We have discussed on the obtained results. 相似文献
832.
Structural,M?ssbauer spectroscopy,magnetic properties,and thermal measurements of Y(3-x)Dy_x Fe_5O_(12) 下载免费PDF全文
Mahdi Lataifeh Qassem I Mohaidat Sami H Mahmood Ibrahim Bsoul Mufeed Awawdeh Ibrahim Abu-Aljarayesh Mu'ath Altheeba 《中国物理 B》2018,(10)
Yttrium iron garnet powder samples((3-x)Dy_x Fe_5O_(12)), where part of yttrium ions are substituted by dysprosium ions with different concentrations are prepared by the solid state reaction method. The properties of the prepared samples are examined by different methods such as x-ray diffraction(XRD), Mssbauer spectroscopy, macroscopic magnetization measurements, and thermal measurements. The XRD measurements show that all the samples reveal the presence of a single garnet phase with a BCC structure. Room temperature Mssbauer spectra indicate that iron ions occupy three magnetic sites, i.e., two octahedral sites and one tetrahedral site. The saturation magnetization and the initial magnetic susceptibility decrease with the increase of Dy~(3+) substitution. The Curie temperature obtained from the thermal measurements seems to be independent of Dy~(3+) substitution. 相似文献
833.
In this paper, a thin film polarizer at the wavelength of 1540 nm in infrared region was designed and optimized using differential evolution method. It is shown how the algorithm’s parameters can change the output result to obtain the best consequence of optimization. This polarizer consists of a few pairs of high and low refractive index dielectric materials, titanium dioxide and silicon dioxide, respectively, with \(BK_{7}\) glass substrate and the angle of incident light was supposed 56° that is the Brewster angle for \(BK_{7}\) glass. Our final optimized polarizer has 91.20 and 0.336% transmittance for P and S polarization, respectively, and a 271 ratio of \(\frac{{T_{P} }}{{T_{S} }}\) which has high significance for this polarizer. It consists of eight pairs of layers with low and high refractive index materials and 3369.1 nm physical thickness which is used to separate S and P polarized light for Q-switching process. 相似文献
834.
Mahdi A. Mohammed Ahmed Fetoh Tamer Awad Ali Magdy M. Youssef Gaber M. Abu El-Reash 《应用有机金属化学》2023,37(1):e6910
Sodium4-hydroxy-3-([2-picolinoylhydrazineylidene]methyl)benzenesulfonate (NaH2PH) was synthesized as a novel water-soluble ligand, by the condensation of picolinohydrazide with sodium 3-formyl-4-hydroxybenzenesulfonate. The (NaH2PH) ligand and its isolated Co (II), Fe (III), Hg (II), and Pd (II) complexes were analyzed by elemental analysis and characterized by spectroscopic (Fourier transform infrared spectroscopy, UV–visible, powder XRD, 1H NMR,13C NMR, MS) and magnetic measurements. By comparing IR spectra of both ligand and the metal complexes, one can assume that the (NaH2PH) ligand behaves as a bi-negative tetradentate (ONNO) in [Co (NaPH)(H2O)2].3H2O, and a mono-negative tridentate (ONO) in [Fe (NaPH)Cl2(H2O)] complex, whereas in [Hg2(NaPH)Cl2(H2O)] complex, (NaH2PH) coordinates as a bi-negative pentadentate (ONNNO) ligand via deprotonated OH group of phenolic ring (C=N)Py and (C=N*) coordinated to one of Hg (II) ion and the oxygen atom of enolic group and (C=N)az group with the another Hg (II) ion. Moreover, (NaH2PH) acts as bi-negative tridentate (ONO) ligand in [Pd (NaPH)(H2O)].2H2O complex. The geometries of complexes were suggested based on the UV–visible spectra, magnetic measurements and confirmed by applying discrete Fourier transform (DFT) optimization studies. The thermal fragmentation of both [Pd (NaPH)(H2O)].2H2O and [Co (NaPH)(H2O)2].3H2O complexes was performed, and the kinetic and thermodynamic parameters were computed using the Coats–Redfern and Horowitz–Metzger methods. The redox behavior of divalent ions of cobalt and mercury were discussed by the cyclic voltammetry technique in the presence and absence of (NaH2PH) ligand. Biological potencies of the ligand and its metal complexes were evaluated as antioxidants (ABTS and DPPH), anticancer, DNA, and antimicrobial (Staphylococcus aureus and Bacillus subtilis as Gram (+) bacteria, Escherichia coli and Pseudomonas aeruginosa as Gram (−) bacteria, and Candida albicans as fungi). 相似文献