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Approximate energies and thermal properties of a position-dependent mass charged particle under external magnetic fields

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Chinese Physics B 2017年第6期26卷 22-30页

作者： m Eshghi h mehraban S m Ikhdair Young Researchers and Elite Club Central Tehran BranchIslamic Azad UniversityTehranIran Faculty of Physics Semnan UniversitySemnanIran Department of Physics Faculty of ScienceAn-Najah National UniversityNablusWest BankPalestine Department of Electrical Engineering Near East UniversityNicosiaNorthern CyprusMersin 10Turkey

We solve the Schrodinger equation with a position-dependent mass（PDm） charged particle interacted via the superposition of the morse-plus-Coulomb potentials and is under the influence of external magnetic and Aharonov–Bohm（AB） flux fields. The nonrelativistic bound state energies together with their wave functions are calculated for two spatially-dependent mass distribution functions. We also study the thermal quantities of such a system. Further, the canonical formalism is used to compute various thermodynamic variables for second choosing mass by using the Gibbs formalism. We give plots for energy states as a function of various physical parameters. The behavior of the internal energy, specific heat, and entropy as functions of temperature and mass density parameter in the inverse-square mass case for different values of magnetic field are shown.

关键词： Schr?dinger equation morse-plus-Coulomb potentials position-dependent mass distribution functions perpendicular magnetic and Aharonov–Bohm flux fields

WEYL'S TYPE ThEOREmS AND hYPERCYCLIC OPERATORS

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Acta mathematica Scientia 2012年第2期32卷 539-551页

作者： m.h.m.Rashid Department of mathematics and Statistics Faculty of ScienceP.O.Box(7)Mu'tah UniversityMu'tah-Jordan

For a bounded operator T acting on an infinite dimensional separable hilbert space h, we prove the following assertions：（i） If T or T＊ ∈ SC, then generalized a- Browder＇s theorem holds for f（T） for every f ∈ hol（σ（T））. （ii） If T or T＊ ∈ hC has topological uniform descent at all λ ∈ iso（a（T））, then generalized Weyl＇s theorem holds for f（T） for every f ∈ hol（σ（T））. （iii） If T ∈ hC has topological uniform descent at all λ ∈（T）, then T satisfies generalized Weyl＇s theorem. （iv） Let T ∈ hC. If T satisfies the growth condition Gd（d 〉 1）, then generalized Weyl＇s theorem holds for f（T） for every f ∈ hol（σ（T））. （v） If T ∈ SC, then, f（OssF＋（T）） = aSBF＋（f（T）） for all f ∈ hol（σ（T））. （vi） Let T be a-isoloid such that T＊ ∈ hC. If T - AI has finite ascent at every A ∈ Eσ（T） and if F is of finite rank on hsuch that TF = FT, then T ∈ F obeys generalized a-Weyl＇s theorem.

关键词： Weyl's theorem hypercyclic operators supercyclic operators

Effect of Ni^(+2)-substituted Fe_2TiO_5 on the h_2-reduction and CO_2 Catalytic Decomposition Reactions at 500℃

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Journal of materials Science & Technology 2006年第6期22卷 846-850页

作者： m.h.Khedr Chemistry Department Faculty of ScienceBenisuef UniversityEgypt

CO2 is a major component of the greenhouse gases, which causes the global warming. To reduce CO2 gas, high activity nanosized Ni＋2 substituted Fe2TiO5 samples were synthesized by conventional ceramic method. The effect of the composition of the synthesized ferrite on the h2-reduction and CO2-catalytic decomposition was investigated. Fe2TiO5 （iron titanate） phase that has a nanocrystallite size of -80 nm is formed as a result of heating Fe2O3 and TiO2 while the addition of NiO leads to the formation of new phases （-80 nm） NiTiO3 and NiFe2O4, but the mixed solid of NiO and Fe2O3 results in the formation of NiFe2O4 only. Samples with Ni^＋2=0 shows the lowest reduction extent （20%）; as the extent of Ni＋2 increases, the extent of reduction increases. The increase in the reduction percent is attributed to the presence of NiTiO3 and NiFe2O4 phases, which are more reducible phases than Fe2TiO5. The CO2 decomposition reactions were monitored by thermogravimetric analysis （TGA） experiments. The oxidation of the h2-reduced Ni＋2 substituted Fe2TiO5 at 500℃ was investigated. As Ni^＋2 increases, the rate of reoxidation increases. Samples with the highest reduction extents gave the highest reoxidation extent, which is attributed to the highly porous nature and deficiency in oxygen due to the presence of metallic Fe, Ni and/or FeNi alloy. X-ray diffraction （XRD） and transmission electron microscopy （TEm） of oxidized samples show also the presence of carbon in the sample containing Ni＋2〉0, which appears in the form of nanotubes （25 nm）.

关键词： Nanocrystallite Ferrite Titanate Reduction CO2 decomposition Carbon nanotubes

Effect of Al powder and silica sol on the structure and mechanical properties of Al_2O_3-ZrO_2 foams

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Acta metallurgica Sinica(English Letters) 2010年第4期23卷 241-247页

作者： h.Sharifi m.Divandari A.Khavandi m.h.Idris School of materials and metallurgical Engineering Iran University of Science and Technology Department of material Engineering Faculty of Mechanical EngineeringUniversti Teknologi Malaysia

Polymeric sponge replication method is one of the common ways for ceramic foam production. The existence of central triangular voids in the struts results in a decrease of mechanical properties limiting their applications. To remove this defect, some additives consisting of Al powder particles and silica sol are added to ceramic slurries consisting of Al2O3 and ZrO2 （partially stabilized zirconia）. With increasing temperature for pyrolyzing and sintering of raw materials, first the Al powder and then the glass phase which consisted of melted Al2O3, ZrO2 and SiO2 was soaked into hollow struts. SEm investigations showed that the center of foam struts were free of hollows. XRD considerations depicted that a ZrO2 phase with tetragonal crystallographic structure is present in the produced foam which could be the reason of improved toughness and mechanical properties. Compressive strength of foams increased significantly due to the decrease of closed porosity. The Weibull statistical study showed remarkable increasing of the Weibull module and its value for foams with 10, 20 and 30 ppi was 5.91, 6.06 and 6.53 respectively.

关键词： Ceramic foam Processing Strut structure Al2O3-ZrO2 Weibull modulus

Analysis of Landau damping in radially inhomogeneous plasma column

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Chinese Physics B 2018年第5期27卷 365-373页

作者： h Rajabalinia-Jelodar m K Salem F m Aghamir h Zakeri-Khatir Plasma Physics Research Center Science and Research BranchIslamic Azad University Department of Physics University of Tehran

The Landau damping behavior in a cylindrical inhomogeneous warm magnetized plasma waveguide has been *** radial inhomogeneity for different characteristic lengths（L0） with strong spatial dispersion has been taken into *** analyses have been considered for two limits ωce 〈 ωpe and ωce 〉 ωpe. Due to the radial inhomogeneity of the plasma, all essential equations for studying the Landau damping are calculated in the Bessel–Furrier and differential Bessel–Furrier expansions. The dependence of Landau damping on the inhomogeneity, temperature and external magnetic field for electrostatic modes is scrutinized and described in detail through numerical calculations. The associated numerical results are presented and discussed.

关键词： inhomogeneous warm plasma cylindrical plasma waveguide Landau damping electrostatic modes

Effect of partition coefficient on microsegregation during solidification of aluminium alloys

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International Journal of minerals,metallurgy and materials 2014年第10期21卷 980-989页

作者： m.h.Avazkonandeh-Gharavol m.haddad-Sabzevar h.Fredriksson Department of metallurgy and materials Engineering Faculty of Engineering Ferdowsi University of Mashhad Department of materials Science and Engineering School of Industrial Engineering and Management Royal Institute of Technology

In the modeling of microsegregation, the partition coefficient is usually calculated using data from the equilibrium phase diagrams. The aim of this study was to experimentally and theoretically analyze the partition coefficient in binary aluminum--copper alloys. The sam- ples were analyzed by differential thermal analysis （DTA）, which were melted and quenched from different temperatures during solidifica- tion. The mass fraction and composition of phases were measured by image processing and scanning electron microscopy （SEm） equipped with an energy-dispersive X-ray spectroscopy （EDS） unit. These data were used to calculate as the experimental partition coefficients with four different methods. The experimental and equilibrium partition coefficients were used to model the concentration profile in the primary phase. The modeling results show that the profiles calculated by the experimental partition coefficients are more consistent with the experi- mental profiles, compared to those calculated using the equilibrium partition coefficients.

关键词： aluminum copper alloys solidification partition coefficient microsegregation numerical modeling differential thermal analysis

The electrical impedance, AC conductivity and dielectric properties of phenol red compound investigated and modeled by an artificial neural network

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Communications in Theoretical Physics 2020年第10期72卷 139-148页

作者： h A m Ali D m habashy Physics Department Faculty of EducationAin Shams UniversityRoxyCairo 11757Egypt

The impedance spectroscopy,electrical conductivity and electric modulus of bulk phenol red were measured,as a function of both frequency and *** neural networks(ANNs)were used for modeling its electrical *** two parts(real and imaginary)of its complex impedance(Z^*)were analyzed and the activation energy related to the electrical relaxation process was *** curves were plotted showing semicircles for the different *** AC electrical conductivity follows a power lawσac(ω)αω^η.The maximum barrier height Bm was derived for specific temperatures.A plausible mechanism for the AC conduction of bulk phenol red was deduced from the temperature reliance of the frequency *** dielectric data was analyzed using electric modulus as a *** addition,ANNs were used to model the impedance parts and the total electrical *** runs were tried,to obtain the best *** training and prediction results were compared to the equivalent experimental results,with a good match *** equation describing the experimental results was obtained mathematically,based on the use of *** outputs demonstrated that ANNs are an admirable tool for modeling experimental results.

关键词： phenol red impedance spectroscopy electric modulus neural network

Petrology, geochemistry, radioactivity, and m–W type rare earth element tetrads of El Sela altered granites, south eastern desert,Egypt

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Acta Geochimica 2019年第1期38卷 95-119页

作者： A.m.El mezayen m.A.heikal m.G.El-Feky h.A.Shahin I.K.Abu Zeid S.R.Lasheen Geology Department Faculty of Science Al Azhar University Nuclear material Authority

The southern part of the Eastern Desert of Egypt—about 30 km southwest of Abu-Ramad city—is mainly covered by ophiolitic rocks(Sul hamed), island arc assemblage, younger granites(muscovite granites of Qash Amer and two mica granites of El Sela), and various acidic and basic dikes. Field, petrological, and geochemical studies indicate that the El Sela shear zone has been subject to hydrothermal and supergene alteration such as kaolinization, albitization, sericitization, and hematitization. It is invaded by quartz ENE–WSW veins associated with hydrothermal alteration accompanied by radioactive mineralization. The investigated younger granitic rocks had very low contents of compatible elements, such as Cr, Ni,and Co; and high contents of incompatible elements, such as Zr, and large ion lithophiles, such as Sr, especially in the El Sela shear zone. major oxide and trace element analyses revealed calc-alkaline affinity and peraluminous *** highly differentiated granitic rocks' lower Zr/hf and higher Y/ho than the normal ratio are consistent with hydrothermal alteration. most samples had rare earth element(REE)-patterns with an m-type tetrad effect in the first and fourth segments and a W-type tetrad in the third segment. The average ∑REE in the studied granites was lower than the world granite average; the ratio of light to heavy REEs greater. The main radioactive, uranium-bearing, and uraniferous Fe and mn minerals are uranothorite,autunite, uranophane and autunite as compounds, kasolite,columbite, xenotime, uranophane-bearing zircon and jarosite, silver-bearing pyrite, hematite, and autunite-bearing pyrolusite.

关键词： Geochemistry REE-tetrad effect Radioactive minerals Radiometric measurements Qash Amer El Sela

Effect of substrate temperature on the morphological,structural,and optical properties of RF sputtered Ge(1-x)Snx films on Si substrate

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Chinese Physics B 2017年第5期26卷 313-318页

作者： h mahmodi m R hashim Nano-Optoelectronics Research Laboratory School of Physics Universiti Sains Malaysia 11800 USM Pulau Penang Malaysia Institute of Nano Optoelectronics Research and Technology (INOR) Universiti Sains Malaysia 11800 USM Pulau Penang Malaysia

In this study, Ge（1-x）Snx alloy films are co-sputtered on Si（100） substrates using RF magnetron sputtering at different substrate temperatures. Scanning electron micrographs, atomic force microscopy（AFm）, Raman spectroscopy, and x-ray photoemission spectroscopy（XPS） are conducted to investigate the effect of substrate temperature on the structural and optical properties of grown Ge Sn alloy films. AFm results show that RmS surface roughness of the films increases from 1.02 to 2.30 nm when raising the substrate temperature. This increase could be due to Sn surface segregation that occurs when raising the substrate temperature. Raman spectra exhibits the lowest FWhm value and highest phonon intensity for a film sputtered at 140℃. The spectra show that decreasing the deposition temperature to 140℃ improves the crystalline quality of the alloy films and increases nanocrystalline phase formation. The results of Raman spectra and XPS confirm Ge–Sn bond formation. The optoelectronic characteristics of fabricated metal-semiconductor-metal photodetectors on sputtered samples at room temperature（RT） and 140℃ are studied in the dark and under illumination. The sample sputtered at 140℃ performs better than the RT sputtered sample.

关键词： sputtering magnetron illumination crystalline raising roughness optoelectronic phonon segregation FWhm