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181.
Magdy A. Ezzat 《Journal of Mathematical Analysis and Applications》2009,353(1):99-2199
In this work, we introduce the modified Ohm's law, including the temperature gradient and charge density effects, and the generalized Fourier's law, including the current density effect, to the equations of the linear theory of micropolar generalized magneto-thermoelasticity, allowing the second sound effects. A normal mode analysis is applied to obtain the exact formulas of temperature, displacement, micro-rotation, stresses, couple stresses, electric field, magnetic field and current density. Application is employed to our problem to get the solution in the complete form. The considered variables are presented graphically and discussions are made. 相似文献
182.
Magdy A. Ezzat Ahmed S. El Karamany 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》2011,62(5):937-952
A new mathematical model of two-temperature magneto-thermoelasticity is constructed where the fractional order heat conduction law is considered. The state space approach is adopted for the solution of one-dimensional application for a perfect conducting half-space of elastic material with heat sources distribution in the presence of a transverse magnetic field. The Laplace-transform technique is used. A numerical method is employed for the inversion of the Laplace transforms. According to the numerical results and its graphs, conclusions about the new theory are given. Some comparisons are shown in figures to estimate the effects of the temperature discrepancy and the fractional order parameter on all the studied fields. 相似文献
183.
Magdy A. Ibrahim Sami A. Al-Harbi Esam S. Allehyani 《Journal of heterocyclic chemistry》2021,58(1):241-249
The reaction of chromone-3-carbonitrile with thiobarbituric acid afforded 2-thioxochromeno[3′,2′:5,6]pyrido[2,3-d]pyrimidine-4,6(1H,3H)-dione, which utilized as a building block for construction of a novel heteroannulated compounds containing chromenopyridothiazolopyrimidine moiety. Reactions of the starting compound with a variety of bielectrophilic reagents namely; chloroacetonitrile, bromomalononitrile, 3-chloropentanedione, ethyl 2-chloro-3-oxobutanoate, phenacyl bromide, chloroacetic acid, dibromoethane, and oxalyl chloride afforded the first known chromenopyridothiazolopyrimidines. Cyclization of the starting compound with 2,3-dichloroquinoxaline gave the linear hepta-annulated chromenopyridopyrimidothiazoloquinoxaline. In addition, chromenopyridopyrimido thiazolopyrimidines were efficiently synthesized. The antimicrobial activity was evaluated for the prepared compounds and some of them seemed notable activity against the tested microorganisms. Analytical and spectral data confirmed the structures of the new products. 相似文献
184.
A convenient synthesis of the dodecanoyl thiosemicarbazide derivatives 3a, b has been achieved from the reaction of 2-benzamido-3-arylacryloylhydrazides 1a, b and lauroyl isothiocyanate (2). The thiosemicarbazide derivative 3a is used as precursor for synthesis of 1,2,4-triazole, 1,3,4-thiadiazole, and 1,3-benzothiazole derivatives. The antimicrobial activity of some of the synthesized compounds was tested. 相似文献
185.
Magdy Assem† 《Compositio Mathematica》2000,120(3):227-290
This article studies unipotent orbital integrals on symplectic and orthogonal groups from the point of view of endoscopy. It begins by partitioning stable unipotent classes into packets and goes on to propose a transfer of these packets. It then discusses (in rough form) the associated transfer factors. Some supporting calculations in split odd orthogonal groups are given. 相似文献
186.
187.
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