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New and facile Synthesis of Substituted Pyrrole, Pyridine, Pyrazolo[4,3-b] Pyridine, Pyrano[3,2-c] Quinoline, Napthopyran, Naphthodipyran and Coumarin Derivatives

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International Journal of Organic Chemistry 2013年第1期3卷 58-70页

作者： f. m. A. el-taweel A. A. elagamey Department of Chemistry Facultyof Science Damietta University Damietta Egypt Department of Chemistry Facultyof Science Damietta University Damietta Egypt.

Several new pyrazolo[4,3-b] pyridines 7a, b were prepared by reacting arylidenemalononitriles 1a, c or 1i, j with 4-nitrosoantipyrine 4. Reacting 1a, b, d with 4-azidomethylcarbonylantipyrine 8 give 2-aminopyrrole 14. Pyrano[3,2-c] quinolines 20a, b and 23 were obtained by reacting 4-hydroxyquinoline 15 with 1g, h, 2b respectively. Reaction of 1 with naphthalenediols 24, 27 and 29 yield naphthodipyrans 26a, b, 28a, b and 30a。

关键词： Pyrrole Pyridine Pyrazolo[4 3-b] Pyridine Pyrano[3 2-c] Quinoline Naphthopyran Naphthodipyrans and Coumarin

Complement-dependent neuroinflammation in spinal cord injury:from pathology to therapeutic implications

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Neural Regeneration Research 2025年第5期20卷 1324-1335页

作者： Hassan Saad Bachar el Baba Ali Tfaily firas Kobeissy Juanmarco Gutierrez Gonzalez Daniel Refai Gerald R.Rodts Christian mustroph David Gimbel Jonathan Grossberg Daniel L.Barrow matthew f.Gary Ali m.Alawieh Department of Neurosurgery Emory University School of MedicineAtlantaGAUSA Department of Neurology Yale UniversityNew HavenCTUSA Center for Neurotrauma Multiomics&Biomarkers(CNMB)Morehouse School of MedicineAtlantaGAUSA

Spinal cord injury remains a major cause of disability in young adults,and beyond acute decompression and rehabilitation,there are no pharmacological treatments to limit the progression of injury and optimize recovery in this *** the thorough investigation of the complement system in triggering and propagating cerebral neuroinflammation,a similar role for complement in spinal neuroinflammation is a focus of ongoing *** this work,we survey the current literature investigating the role of complement in spinal cord injury including the sources of complement proteins,triggers of complement activation,and role of effector functions in the *** study relevant data demonstrating the different triggers of complement activation after spinal cord injury including direct binding to cellular debris,and or activation via antibody binding to damage-associated molecular *** effector functions of complement have been implicated in spinal cord injury,and we critically evaluate recent studies on the dual role of complement anaphylatoxins in spinal cord injury while emphasizing the lack of pathophysiological understanding of the role of opsonins in spinal cord *** this pathophysiological review,we systematically review the different translational approaches used in preclinical models of spinal cord injury and discuss the challenges for future translation into human *** review emphasizes the need for future studies to dissect the roles of different complement pathways in the pathology of spinal cord injury,to evaluate the phases of involvement of opsonins and anaphylatoxins,and to study the role of complement in white matter degeneration and regeneration using translational strategies to supplement genetic models.

关键词： complement neuroinflammation neuroplasticity regeneration spinal cord injury targeted therapy

formation of Alfvénic supernonlinear waves in a plasma containing double spectral distributed electrons

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Communications in Theoretical Physics 2024年第12期76卷 140-149页

作者： A A el-Tantawy W f el-Taibany S K el-Labany A m Abdelghany Department of Physics Faculty of Science Damietta University Center of Space Research and Its Application Damietta University

The characteristics of nonlinear and supernonlinear Alfvén waves propagating in a multicomponent plasma composed of a double spectral electron distribution and positive and negative ions were investigated. The Sagdeev technique was employed, and an energy equation was derived. Our findings show that the proposed system reveals the existence of a double-layer solution, periodic, supersoliton, and superperiodic waves. The phase portrait and potential analysis related to these waves were investigated to study the main features of existing waves. It was also found that decreasing the electron temperature helps the superperiodic structure to be excited in our plasma model. Our results help interpret the nonlinear and supernonlinear features of the recorded Alfvén waves propagating in the ionosphere D-region.

关键词： Alfvén waves double spectral distribution nonlinear waves Sagdeev method supernonlinear waves

HARmONIC, SUBHARmONIC, SUPERHARmONIC, SImULTANEOUS SUB/SUPER HARmONIC AND COmBINATION RESONANCES Of Self-EXCITED TWO COUPLED SECOND ORDER SYSTEmS TO mULTI-fREQUENCY EXCITATION

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Acta mechanica Sinica 1993年第1期9卷 61-71页

作者： A.m.elnaggar A.f.el-Basyouny mathematics Department Faculty of ScienceBenha Egypt

Harmonic, subharmonic, superharmonic, simultaneous sub/super harmonic, and combination resonances of the additive type of self-excited two coupled-second order systems to multi-frequency excitation are investigated. The theoretical results are obtained by the multiple-scales method. The steady state amplitudes for each resonance are plotted, showing the influence of the different parameters. Analysis for each figure is given. Approximate solution corresponding to each type of resonance is determined. Stability analyses are carried out for each case.

关键词： resonance nonlinear oscillation multiple-scales method self-excited system multi-frequency excitation

fluoride distribution and the effect of some ions along Alexandria coastal mediterranean seawater of Egypt

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Journal of Environmental Sciences 2003年第5期15卷 639-646页

作者： W.m.el-Sarraf m.S.masoud A.A.Harfoush GH.f.el-Said NationalInstituteofOceanographyandfisheries ChemistryDepartmentChemistryDepartmentNationalInstituteofOceanographyandFisheries AlexandriaEgyptFacultyofScienceAlexandriaUniversityEgyptFacultyofScienceAlexandriaUniversityEgyptAlexandriaEgypt

The coastal seawater of mediterranean of Alexandria receives large amount of discharged waters containing industrial wastes, sewage, and agricultural and domestic drainage. fluoride and some parameters were(chemical and physical) determined. The data gave indication that the content and the amount of the discharged water largely affect the chemical composition of the coastal water. Stepwise regression analysis was highly significant and the model was very fruitful, where the observed and calculated values were mostly concordant. This may indicated that there was a relation between fluoride content in coastal seawater and its content in the discharged water.

关键词： fluoride distibution Alexandria costal mediterranean Egypt physical and chemical parametrs regression analysis

Simulation of buoyancy-induced turbulent flow from a hot horizontal jet

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Journal of Hydrodynamics 2014年第1期26卷 104-113页

作者： el-AmIN m.f. SUN Shuyu SALAm Amgad Computational Transport Phenomena Laboratory (CTPL) Division of Physical Sciences and EngineeringKing Abdullah University of Science and Technology

Experimental visualizations and numerical simulations of a horizontal hot water jet entering cold water into a rectangular storage tank are described. Three different temperature differences and their corresponding Reynolds numbers are considered. Both experimental visualization and numerical computations are carried out for the same flow and thermal conditions. The realizable k-e model is used for modeling the turbulent flow while the buoyancy is modeled using the Boussinesq approximation. Polynomial approximations of the water properties are used to compare with the Boussinesq approximation. Numerical solutions are obtained for unsteady flow while pressure, velocity, temperature and turbulence distributions inside the water tank as well as the froude number are analyzed. The experimental visualizations are performed at intervals of five seconds for all different cases. The simulated results are compared with the visualized results, and both of them show the stratification phenomena and buoyancy force effects due to temperature difference and density variation. After certain times, depending on the case condition, the flow tends to reach a steady state.

关键词： turbulent flow realizablc k - e turbulence model heat transfer jet heat storage

electrical Conductivity and Sensitive Characteristics of Ag-Added BaTiO_3-CuO mixed Oxide for CO_2 Gas Sensing

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Journal of materials Science & Technology 2011年第1期27卷 35-40页

作者： A.m.el-Sayed f.m.Ismail S.m.Yakout Inorganic Chemistry Department National Research CentreTahrir StreetDokki P.C.12622 CairoEgypt

Carbon dioxide gas sensors based on BaTiO3-CuO composite with different concentrations of Ag addition（1,1.5 and 2 wt%） have been prepared by stander ceramic method and sintered at 500 and 700℃ for 5 *** conductivity and gas sensing properties of the prepared samples were *** conductivity measurement was used to characterize the obtained sintered sensor *** was found that electrical conductivity and the sensitivity to CO2 were improved with Ag addition and *** correlation between Ag content at different sintering temperature and sensing characteristics towards CO2 is discussed.

关键词： BaTiO3-CuO composite Ag addition electrical conductivity CO2 sensitive properties

Numerical Study of Greenhouse Nocturnal Heat Losses

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Journal of Thermal Science 2011年第4期20卷 377-384页

作者： f.Berroug E.K.Lakhal m.el Omari m.faraji H.el Qarnia Laboratoire d'Automatique de l'Environnement et Procédés de Transfert UniversitéCadi AyyadFacultédes Sciences Semlalia-Département de PhysiqueMarrakech-MarocAffiliéau CNRSTURAC 28 Laboratoire de Physique des materiaux MicroelectroniqueAutomatique et TechniqueDepartement de PhysiquesFaculte des Sciences Ain ChockUniversite Hassan IICasablanca-Maroc

In this study we quantify and analyze different components of nocturnal losses from a heated greenhouse with the presence of vegetation for typical winter weather conditions in marrakesh-morocco,using a non linear model,based on the greenhouse heat and mass *** was found that 12% of the total input heat was dissipate as a sensible and latent leakage losses,66% was lost by convective exchange through air-inner *** gain of energy at the inner-cover is dissipated at the outer-cover by radiation(66%)and convection(34%).This results point toward some practical measures to reduce heat losses:increasing air tightness,using covering materials with low-emissivity in the long wave band or putting up an external thermal curtain should provide significant energy savings.

关键词： Greenhouse energy balance heat losses numerical analysis.

Nonlinear Dust Acoustic Waves in Dissipative Space Dusty Plasmas with Superthermal electrons and Nonextensive Ions

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Communications in Theoretical Physics 2016年第5期65卷 606-612页

作者： A.m.el-Hanbaly E.K.el-Shewy m.Sallah H.f.Darweesh Theoretical Physics Research Group Physics Department Faculty of Science Mansoura University Department of Physics Taibah University

The nonlinear characteristics of the dust acoustic(DA)waves are studied in a homogeneous,collisionless,unmagnetized,and dissipative dusty plasma composed of negatively charged dusty grains,superthermal electrons,and nonextensive *** pseudopotential technique has been employed to study the large amplitude DA ***(Sagdeev pseudopotential)has an evidence for the existence of compressive and rarefractive *** global features of the phase portrait are investigated to understand the possible types of solutions of the Sagdeev *** the other hand,the reductive perturbation technique has been used to study small amplitude DA waves and yields the Korteweg-de Vries-Burgers(Kd V-Burgers)equation that exhibits both soliton and shock *** behavior of the obtained results of both large and small amplitude is investigated graphically in terms of the plasma parameters like dust kinematic viscosity,superthermal and nonextensive parameters.

关键词： Sagdeev pseudopotential KdV-Burgers equation soliton and shock waves reductive perturbation dust kinematic viscosity