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151.
Taha M. A. Eldebss Ahmad M. Farag Mohamed M. Abdalla Ahmad A. Khedr 《Journal of heterocyclic chemistry》2019,56(3):765-780
A new series derived from 4‐(2‐chloroacetyl)‐1,2‐dihydro‐2,3‐dimethyl‐1‐phenylpyrazol‐5‐one was synthesized and characterized, and its pharmacological activity toward α‐glucosidase and α‐amylase enzyme inhibition was screened. Moreover, molecular docking studies were conducted to support the findings. 相似文献
152.
Nashwa El‐Metwaly Ismail Althagafi Hanadi A. Katouah Jabir H. Al‐Fahemi Tahani M. Bawazeer Abdalla M. Khedr 《应用有机金属化学》2019,33(9)
New VO (II)‐thaizolyl hydrazine complexes were synthesized and characterized by analytical, spectral and theoretical techniques. Bi‐nuclear complexes were suggested for all synthesizes upon neutral poly‐dentate mode of bonding. UV–Vis and EPR spectra, proposed two structural geometries as, square‐planer and octahedral. TGA confirmed the contribution of solvent molecules through physical and/or coordinate‐bonding. XRD parameters calculated, displayed outstanding nanometer‐sizes for all nano‐crystalline compounds, which suffering slight imperfections. Also, SEM images showed, spherical‐shape that observed for most topographic particulates. Conformational study executed for all new synthesizes, demonstrated their optimized structural‐forms. Furthermore, important physical parameters were computed that predict essential characteristics as, biological efficiency. Predictable parameters as softness and electrophilicity, point to priority of VO (II)‐4d complex. Genotoxic study, was already examined, for all new synthesizes, against CT‐DNA and displayed complete deterioration for DNA, by influence of most tested compounds. Moreover, MOE‐docking technique, was executed against receptors of Y‐family DNA‐polymerase (4irk) and Key‐Enzyme Linking‐Metabolic Inflammation (4cyf). This docking study displayed the following ascending order; VO (II)‐4c,4irk ? VO (II)‐4d,4cyf ? VO (II)‐4c, 4cyf ? VO (II)‐4b, 4cyf, based on scoring‐energy values. This study concluded with promising prediction of these complexes in relation to DNA‐polymerase as well as inflammation enzyme that compared with known anti‐inflammatory drug (meloxicam). 相似文献
153.
Green synthesis approach for novel benzenesulfonamide nanometer complexes with elaborated spectral,theoretical and biological treatments
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Jabir H. Al‐Fahemi Abdalla M. Khedr Ismail Althagafi Nashwa M. El‐Metwaly Fawaz A. Saad Hanadi A. Katouah 《应用有机金属化学》2018,32(9)
New series of nano‐sized bi‐homonuclear Ce (III), ZrO (II), Sn (II), Pb (II), Cr (III), Fe (III) and Cu (II) complexes with 4‐[(2,4‐dihydroxybenzylidene)amino]‐N‐(1,3‐thiazol‐2‐yl) benzenesulfonamide (H3L) were synthesized via green solid‐state method. The structural and molecular formulae of all synthesized complexes were established based on variable spectral, analytical and theoretical implementations. FT‐IR study confirms the coordination of H3L with metal ions through the Schiff base and sulfonamide centers in di‐basic tetra‐dentate mode. Thermal analysis, magnetic moment and electronic spectra are attributing to octahedral configuration around Ce (III), Cr (III) and Fe (III) centers, while with ZrO (II), Sn (II), Pb (II) and Cu (II) centers, acquired tetrahedral arrangement. TEM and XRD studies, represent the nanometer characters of most metal ion complexes. TGA curves are utilized to compute the activation thermo‐kinetic parameters over different decomposition stages applying Coats‐Redfern method. Theoretical implementation executed by Gaussian09 program exerted the structures for the best atomic orientation over whole molecules. QSAR data were achieved over Hyper Chem 8.1 program through molecular mechanics process. Docking complexes between free ligand and different protein receptors were obtained through AutoDock Tools 4.2. Antimicrobial, antifungal and antitumor activities of the metal complexes were studied in comparing with free ligand to assert their potential therapeutic uses. H3L, Ce (III), Fe (III) and Cu (II) complexes displayed high antibacterial activity near that of standard Gentamycin. Moreover, Cr (III) complex displayed highest cytotoxicity against human liver Carcinoma cell line (HEPG2). 相似文献
154.
Mohamed Abdalla Darwish John R Graef Kishin Sadarangani 《Journal of Applied Analysis & Computation》2018,8(1):331-343
In this paper the authors study a fractional quadratic integral equation of Urysohn-Volterra type. They show that the integral equation has at least one monotonic solution in the Banach space of all real functions defined and continuous on the interval $[0,1]$. The main tools in the proof are a fixed point theorem due to Darbo and a monotonicity measure of noncompactness. 相似文献
155.
Maha El-Tohamy Sawsan Razeq Magda El-Maamly Abdalla Shalaby 《Central European Journal of Chemistry》2010,8(4):937-945
The construction and performance characteristics of phenytoin sodium selective electrodes are detailed. Two types of electrodes:
plastic membrane I and coated wire II, were constructed based on the incorporation of phenytoin sodium with tungstosilicic
acid. The influence of membrane composition, kind of plasticizer, pH of the test solution, soaking time and the electrodes’
foreign ions were investigated. The electrodes showed a Nernstian response with a mean calibration graph slope of 30.9±0.1
and 28.9±0.1 mV decade−1 at 25°C for electrode I and II respectively, over a phenytoin sodium concentration range of 5×10−3−5×10−6 M and 1×10−3−1×10−6 M with a detection limit 1.3×10−6 M and 2.5×10−7 M for electrode I and II, respectively. The electrodes gave average selective precision and were usable within the pH range
6–10. Interference studies from common cations, alkaloids, sugars, amino acids and drug excipients are reported. The results
obtained by the proposed electrodes were also applied successfully for the determination of the drug in pharmaceutical preparations
and biological fluids. 相似文献
156.
From 1540 inelastic interactions of 3.7 A GeV~(16)O projectile with emulsion nuclei, we select samples of 87 and61 events carefully due to interactions of neutron(n) and singly charged particles(Z = 1), respectively. New results concerning the topology of such events are investigated. The average multiplicities of secondary relativistic particles that appear as shower tracks for n and Z = 1 stay more or less constant when compared with analogous data on p-Em at similar energy. The multiplicity distributions and the average values of the various secondary charged particles are studied and compared with the corresponding predictions by the cascade evaporation model.The results assume that the n or Z = 1 from~(16)O collide peripherally with an emulsion target and are considered as an expansion to the N-N collisions. 相似文献
157.
A full quantum treatment of the problem of quantum non-demolition measurements in non-linear optical media is considered. The system consists of four different coupling parameters in addition to different phase parameters. The solution of the Heisenberg equations of motion for the dynamical operators is obtained. The phenomenon of squeezing is examined for both normal and principal squeezing and it has been shown that it is more pronounced for the compound mode case. The intensity correlation function is also calculated and discussed where the observation of the antibunching can be reported. In addition to the higher-order moments we examined the quantum correlation functions, joint quasidistribution functions, as well as photon-number distribution and its factorial moments. It has shown that the non-classical properties is apparent of this system and more pronounced for the compound mode (1,3). 相似文献
158.
159.
M. Sebawe Abdalla M. Abdel-Aty A.-S. F. Obada 《International Journal of Theoretical Physics》2007,46(3):637-651
The behavior of a modified Jaynes-Cummings Hamiltonian model (two-level atom in interaction with an electromagnetic field)
in the presence of degenerate parametric amplification is introduced. We have examined two different cases, one when the field
frequency ω is not equal to the splitting photon frequency ε for which the off-resonance case is considered. In the second
case we have taken each frequencies to be equal (ω = ε) and considered the system to be at exact resonance. The wave function
for both cases is obtained and the result used to calculate the density matrix from which we manage to discuss the field entropy
as well as the phase entropy. It is shown that the system is sensitive to any change in the splitting photon frequency ε. 相似文献
160.
Abdalla M. Al-Amiri Khalil Khanafer Marilyn F. Lightstone 《Heat and Mass Transfer》2006,42(11):1007-1015
A numerical study is conducted on time-dependent double-diffusive natural convection heat transfer in a horizontal annulus. The inner cylinder is heated with sinusoidally-varying temperature while the outer cylinder is maintained at a cold constant temperature. The numerical procedure used in the present work is based on the Galerkin weighted residual method of finite-element formulation by incorporating a non-uniform mesh size. Comparisons with previous studies are performed and the results show excellent agreement. In addition, the effects of pertinent dimensionless parameters such as the thermal Rayleigh number, Buoyancy ratio, Lewis number, and the amplitude of the thermal forcing on the flow and heat transfer characteristics are considered in the present study. Furthermore, the amplitude and frequency of the heated inner cylinder is found to cause significant augmentation in heat transfer rate. The predictions of the temporal variation of Nusselt and Sherwood numbers are obtained and discussed. 相似文献