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Search Results: 1 - 10 of 558987 matches for " A. H. Bayoumi "
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Metal complexes of triazine - Schiff bases: Spectroscopic and thermodynamic studies of complexation of some divalent metal ions with 3-(a-acetylethylidenehydrazino)-5,6-diphenyl-1,2,4-triazine
Journal of the Serbian Chemical Society , 1999,
Abstract: Metal complexes of some divalent metal ions (Co, Ni, Cu and Zn) with 3-(a-acetylethylidenehydrazino)-5,6-diphenyl-1,2,4-triazine (AHDT) as a Schiff-base have been investigated potentiometrically and spectrophotometrically and found to have the stoichiometric formulae 1:1 and 1:2 (M:L). The formation constants of the proton-ligand and metal-ligand complexes have been determined potentiometrically at different temperatures (10, 20, 30, 40 and 50°C) at an ionic strength of 0.1 M KNO3 in 75% (v/v) dioxane-water solution. The standard thermodynamic parameters, viz. DG°, DH°, and DS°, for the proton-ligand and the stepwise metal-ligand complexes have been evaluated.
Synthesis of Pyrroles and Condensed Pyrroles as Anti-Inflammatory Agents with Multiple Activities and Their Molecular Docking Study  [PDF]
M. T. Sarg, M. M. Koraa, A. H. Bayoumi, S. M. Abd El Gilil
Open Journal of Medicinal Chemistry (OJMC) , 2015, DOI: 10.4236/ojmc.2015.54005
Abstract: We herein disclose a series of novel pyrrole derivatives as well as fused pyrrolopyridines 6a,b and 7a,b, pyrrolopyrazoles 8a, b, pyrrolo[2,3-d]pyrimidine derivatives 10a-d, 12a,b, 14a,b, 18a,b, 20a,b, 21a,b, 22a,b, 23a,b, 24a,b, 31a,b, 36a,b, 40a,b, pyrrolo[1,2,6]thiadiazine derivatives 19a,b, pyrrolotriazolopyrimidines 25a,b, 26a,b, 27a,b and 28a,b, pyrrolo[2,3-d][1,2,3]triazine derivatives 32a,b and pyrrolo[2,3-d][1,3]oxazine derivatives 39a,b as novel compounds. All compounds were evaluated for their anti-inflammatory, analgesic (compared to the reference drug Indomethacin) and antimicrobial activities (compared to the reference drug Ampicillin and Fluconazole). Compounds 4d, 5b-d, 6a,b, 9c,d, 10d, 12ab, 13b, 19a,b, 21b, 23b, 31a,b, 38b and 40a were found to be the most active anti-inflammatory drugs exhibiting potency ranging from 1 - 1.01 compared to the reference drug indomethacin. In addition to docking study of these highly active twenty compounds against the active site of cyclooxygenase-2 enzyme (COX-2), among the tested compounds, compounds 5d, 9d, 11b, 12a, 13b and 32a showed multiple activities; anti-inflammatory, analgesic and anti-bacterial activities.
A Novel One-Pot and Efficient Procedure for Synthesis of New Fused Uracil Derivatives for DNA Binding  [PDF]
Bothaina A. Mousa, Ashraf H. Bayoumi, Makarem M. Korraa, Mohamed G. Assy, Samar A. El-Kalyoubi
International Journal of Organic Chemistry (IJOC) , 2015, DOI: 10.4236/ijoc.2015.51005
Abstract: Hydrazinolysis of 6-chloro-1-methyluracil followed by condensation of the product with different aromatic aldehyde gives the respective hydrazones which undergoes oxidative cyclization using thionyl chloride to obtain pyrazolo[3,4-d]pyrimidines in good yields. On the other hand, nitrosation of 6-aminouracils followed by the reaction with different arylidineanilines gives new xanthine derivatives. Finally, indenopyrrolopyrimidine and indenopteridine are obtained in good yields via the reaction of 6-aminouracils and 5,6-diaminouracil with ninhydrin respectively. The newly synthesized compounds show binding, chelation and fragmentation of the nucleic acid DNA.
Evaluation of the Properties of Cemented Liquid Scintillator Wastes under Flooding Scenario in Various Aqueous Media
H. El-Didamony,T. A. Bayoumi,M. I. Sayed
ISRN Chemical Engineering , 2012, DOI: 10.5402/2012/373795
Evaluation of the Properties of Cemented Liquid Scintillator Wastes under Flooding Scenario in Various Aqueous Media
H. El-Didamony,T. A. Bayoumi,M. I. Sayed
ISRN Chemical Engineering , 2012, DOI: 10.5402/2012/373795
Abstract: Experiments simulating flooding scenario in various aqueous media for a long period were carried out to determine the adequacy of cement-clay composite for solidification/stabilization of spent organic radioactive liquid scintillator wastes. The final cement waste form blocks were immersed in three aqueous media, namely, seawater, groundwater, and tapwater. The immersion process lasted for increasing periods up to 540 days. Following each predetermined interval period, physical and mechanical evaluations of the immersed blocks were determined. In addition, the change in the hydration products was followed by X-ray diffraction and infrared spectroscopy as nondestructive analyses to recognize the deterioration in the microstructure that may occur due to the flooding event. Thermal analysis and scanning electron microscopy were performed to confirm the data obtained. 1. Introduction To determine the radioactivity contents in any specimen based on liquid scintillation technique, the sample under quantification is dissolved or suspended in a cocktail containing an aromatic solvent (e.g., benzene, toluene, and dioxan) and predetermined amounts of other additives known as flours, that is, scintillator. The particles emitted from the radioisotope in the sample transfer their energies to the solvent which in turn transfers that energy to the flours’ molecules that dissipating the energy by emitting light. After this quantification, the spent liquid scintillators are counted as a hazardous organic radioactive waste and should be managed safely [1–3]. This waste could be classified as problematic waste for further processing because of the specific radioactive contamination and the organic nature of this waste. Special treatment options should be developed to address both these characteristics of that waste [4]. The practice of immobilizing radioactive waste with ordinary Portland cement began during the early years of the nuclear industry. This was primarily due to its low cost, availability, and compatibility with aqueous waste. It was soon realized, however, that specific wastes, like scintillator liquid, interact with the cement components causing inhibition or retarding the hydration reaction. To overcome these drawbacks, one or more selected additives were added to the Portland cement mixtures. Several of the more successful mixtures such as sodium silicate, reactive silica, lime, clay, and slag have been identified and commercialized [5]. Solidification/stabilization (s/s) using cement is a chemical treatment process aiming at either binding or
Simulating Annealing PLL for Autonomous Microgrid Systems  [PDF]
Ehab H. E. Bayoumi
Smart Grid and Renewable Energy (SGRE) , 2019, DOI: 10.4236/sgre.2019.105009
Abstract: The Phase Locked Loop controller parameters are the key-point that affects the dynamic performance of the autonomous microgrid. They have to be optimally tuned to guarantee enhanced overall system stability. In this paper, two-microgrid plant with their associate PWM inverter connected to the ac main grid and the load is used as an example to demonstrate the capabilities of the proposed system. The Phase Locked Loop controller is designed and tuned using the Simulating Annealing algorithm. This algorithm is used to select the Phase Locked Loop PI controller gains with optimal percentage overshoot, rise time and settling time. The controller is tested during the transition between grid-connected and autonomous operation and in reverse order. The controller is compared with Ziegler and Nichols P and PI controllers. It shows the effectiveness and the extraordinary control response of the proposed control technique with respect to percentage overshoot, rise time and settling time control parameters compared to the conventional one.
Low-Power Distributed Kalman Filter for Wireless Sensor Networks
A. Abdelgawad,M. Bayoumi
EURASIP Journal on Embedded Systems , 2011, DOI: 10.1155/2011/693150
Characteristic Studies of Hexamethylene Diamine Complexes
Hoda A. Bayoumi
International Journal of Inorganic Chemistry , 2013, DOI: 10.1155/2013/458018
Abstract: Preparation and chemical analysis of Mn(II), Fe(III), Co(II), Ni(II), and Zn(II) complexes with Schiff base L [o-HOC6H4CH:N(CH2)6N:CHC6H4OH-o] are the main tasks of this work. The octahedral (M2L2·nH2O·X) complexes in 1?:?1 M?:?L ratio (X = or Ac? group, L = ligand) were prepared by involving the hydroxylic group in ortho position. All complexes were characterized on the basis of elemental analysis, UV, IR, 1H NMR, Gc/Ms, thermogravimetric analysis, magnetic measurements, molar conductance, and electrical conductivity. The obtained data indicate that all the investigated compounds behave as semiconductor materials. 1. Introduction The chemistry of transition metal complexes of Schiff base compounds hasattracted a lot of interest in the field of bioinorganic and coordination chemistry [1–4]. The presence of ion pair on the nitrogen atom of imino group enables the coordination of numerous metal cations [5]. Transition metal complexes with oxygen and nitrogen donor Schiff bases are of particular interest because of their ability to possess unusual configuration that is structurally labile and their sensitivity to molecular environments [6, 7]. Schiff base can also accommodate different anions of the same center metal involving various coordination modes, thereby allowing successful synthesis of homo- and heterometallic complexes with varied stereochemistry. This feature is employed for modeling active sites in biological system [8–11]. In regard to importance of these compounds, many literatures have been published in this field. In view of this recently, multicomponent has much attention, and many of them have been reported. The desired Schiff base was obtained when 1,6-hexanediamine was condensed with salicylaldehyde. The structures of Mn(II), Fe(III), Co(II), Ni(II), and Zn(II) complexes were confirmed by elemental analysis, infrared and UV-Visible spectra, thermogravimetric analysis, magnetic measurements, and molar conductance. 2. Experimental 2.1. Physical Measurements Infrared measurements were carried out on Perkin Elmer spectrophotometer model 1430 in range from 200 to 4000?cm?1. Ultraviolet and visible spectra were carried out on a Perkin Elmer Lambda 35 UV-Vis spectrophotometer in the range 190–500?nm. The solution spectra of ligands and complexes were carried out in 10?6?M of DMF. 1H-NMR spectra were recorded using a Varian spectrometer, 200?MHz. Thermal gravimetric analysis (TGA) data were measured from room temperature to 650°C at heating rate of 10°C/min. The data were obtained using a Shimadzu TGA-50H instrument. Mass spectra of the
Magdy A. Bayoumi,Bertrand Zavidovique
EURASIP Journal on Advances in Signal Processing , 2005, DOI: 10.1155/asp.2005.989
Powder Metallurgical Fabrication and Microstructural Investigations of Aluminum/Steel Functionally Graded Material  [PDF]
Mahmoud M. Nemat-Alla, Moataz H. Ata, Mohamed R. Bayoumi, Wael Khair-Eldeen
Materials Sciences and Applications (MSA) , 2011, DOI: 10.4236/msa.2011.212228
Abstract: Aluminum/steel electric transition joints (ETJs) are used in aluminum reduction cell for the purpose of welding aluminum rod and steel bracket components. Solid state welding process used for joining aluminum and steel at the electric transition joints have the drawbacks of cracking and separation at the interface surfaces. Cracking and separation at the electric transition joints are caused by the stress singularities that developed due to the mismatch in thermal and mechanical properties of each material. To overcome the drawback of electric transition joints, aluminum/steel functionally graded may be used as electric transition joints or proposed. Therefore manufacturing and investigation of aluminum/steel functionally graded materials fabricated by powder metallurgy process were carried out through the current work. Different samples with different layers of aluminum/steel functionally graded materials were compacted using steel die and punch at the same compacted pressure and sintered temperature. After investigating the different samples of aluminum/steel functionally graded materials under different fabrication conditions, the suitable fabrication regime was determined with the aid of microscopic observations.
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