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821.
Aida Esmaeilian-Marnani Ahmad Fauzi Abas Mohd Adzir Mahdi Khairulmizam Samsudin 《Optical Review》2012,19(2):71-77
Propagation of temporal 50 femtosecond pulse and pulse stream, which is realized by substituting each input pulse with reduced-order
overlapping soliton pair, is investigated through short standard single-mode fiber. For the pulse stream the initial inter-pulse
delay is selected to be 227 fs and the pulses are to be perturbed to avoid collision with the neighboring pulses. This method
reduces the pulse time delay and properly retains the amplitude despite tradeoff between these two. This is a significant
improvement in the low power femtosecond pulse and pulse stream propagation. 相似文献
822.
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