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Chinese Physics Letters 2008年第12期25卷 4240-4243页

作者： i. i. Guseinov Department of Physics Faculty of Arts and Sciences Onsekiz Mart University Canakkale Turkey

The expansion formulas in terms of complete orthonormal sets of ψ^α -exponential type orbitals are established for the Slater type orbitals and Coulomb-Yukawa-like correlated interaction potentials of integer and noninteger indices. These relations are used in obtaining their unsymmetrical and symmetrical one-range addition theorems. The final results are especially useful in the calculations of multicentre multielectron integrals occurring when Hartree-Fock-Roothaan and explicitly correlated methods are employed.

关键词： orthonormal set expansion formula

The effect of forced oscillations on the kinetics of wave drift in an inhomogeneous plasma

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Plasma Science and Technology 2020年第12期22卷 8-19页

作者： V i EROFEEV institute of Automation&Electrometry of the Siberian Branch of the Russian Academy of Sciences 1 Koptyug Prosp.630090NovosibirskRussia Novosibirsk State University 2 Pirogova Str.NovosibirskRussia

The kinetics is analyzed of the drift of non-potential plasma waves in spatial positions and wavevectors due to plasma's spatial inhomogeneity. The analysis is based on highly informative kinetic scenarios of the drift of electromagnetic waves in a cold ionized plasma in the absence of a magnetic field(Erofeev 2015 Phys. Plasmas 22 092302) and the drift of long Langmuir waves in a cold magnetized plasma(Erofeev 2019 J. Plasma Phys. 85 905850104). it is shown that the traditional concept of the wave kinetic equation does not account for the effects of the forced plasma oscillations that are excited when the waves propagate in an inhomogeneous *** are highlighted that account for these oscillations in the kinetic equations of the abovementioned highly informative wave drift scenarios.

关键词： informativeness of plasma kinetic scenario the ensemble method asymptotic convergence of perturbation theories correlation analysis of plasma kinetics kinetic equation of wave drift in phase space

S-doped carbon aerogels/GO composites as oxygen reduction catalysts

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Journal of Energy Chemistry 2016年第2期25卷 234-243页

作者： Mykola Seredych Krisztina László Enrique Rodríguez-castellón Teresa J.Bandosz The City College of New York and The Graduate Center of CUNY Department of Chemistry 160 Convent Avenue New York NY 10031 USA Department of Physical Chemistry and Materials Science Budapest University of Technology and Economics Budapest 1521 Hungary Departamento de Quimica inorganica Universidad de Malaga Malaga 29071 Spain

Composites of carbon aerogel and graphite oxide（GO） were synthesized using a self-assembly method based on dispersive forces. Their surface was modified by treatment in hydrogen sulfide at 650 and800 ℃. The samples obtained were characterized by adsorption of nitrogen, TA-MS, XPS, potentiometric titration, and HRTEM and tested as catalysts for oxygen reduction reactions（ORR） in an alkaline *** synergistic effect of the composite（electrical conductivity, porosity and surface chemistry） leads to a good ORR catalytic activity. The onset potential for the composite of carbon aerogel heated at 800 ℃ is shifted to a more positive value and the number of electron transfer was 2e-at the potential 0.68 V versus RHE and it increased to 4e-with an increase in the negative values of the potential. An excellent tolerance to methanol crossover was also recorded.

关键词： Oxygen reduction reaction Carbon aerogel/GO composites Porosity Surface chemistry Specific interactions

Unified treatment for accurate and fast evaluation of the Fermi-Dirac functions

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Chinese Physics B 2010年第5期19卷 72-77页

作者： i.i.Guseinov B.A.Mamedov Department of Physics Faculty of Arts and SciencesOnsekiz Mart UniversityCanakkaleTurkey Department of Physics Faculty of Arts and SciencesGaziosmanpa sa UniversityTokatTurkey

A new analytical approach to the computation of the Fermi-Dirac （FD） functions is presented, which was suggested by previous experience with various algorithms. Using the binomial expansion theorem these functions are expressed through the binomial coefficients and familiar incomplete Gamma functions. This simplification and the use of the memory of the computer for the calculation of binomial coefficients may extend the limits to large arguments for users and result in speedier calculation, should such limits be required in practice. Some numerical results are presented for significant mapping examples and they are briefly discussed.

关键词： statistical semiconductors plasma physics nuclear physics

The sexually dimorphic expression of glutamate transporters and their implication in pain after spinal cord injury

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Neural Regeneration Research 2025年第11期20卷 3317-3329页

作者： Jennifer M.Colón-Mercado Aranza i.Torrado-Tapias iris K.Salgado Jose M.Santiago Samuel E.Ocasio Rivera Dina P.Bracho-Rincon Luis H.Pagan Rivera Jorge D.Miranda Department of Physiology University of Puerto RicoMedical Sciences CampusSan JuanPRUSA National institutes of Health National Human Genome Research InstituteBethesdaMDUSA Universidad Central del Caribe School of MedicineBayamónPRUSA University of Puerto Rico Carolina CampusCarolinaPRUSA institute of Neurobiology San JuanPRUSA

in addition to the loss of motor function,~60% of patients develop pain after spinal cord *** cellular-molecular mechanisms are not well understood,but the data suggests that plasticity within the rostral,epicenter,and caudal penumbra of the injury site initiates a cellularmolecular interplay that acts as a rewiring mechanism leading to central neuropathic *** can lead to the formation of new connections triggering abnormal sensory *** excitatory glutamate transporters are responsible for the reuptake of extracellular glutamate which makes them a critical target to prevent neuronal hyperexcitability and *** previous studies showed a sexually dimorphic therapeutic window for spinal cord injury after treatment with the selective estrogen receptor modulator *** this study,we investigated the anti-allodynic effects of tamoxifen in male and female rats with spinal cord *** hypothesized that tamoxifen exerts anti-allodynic effects by increasing the expression of glutamate transporters,leading to reduced hyperexcitability of the secondary neuron or by decreasing aberrant *** and female rats received a moderate contusion to the thoracic spinal cord followed by subcutaneous slow-release treatment of tamoxifen or matrix pellets as a control(placebo).We used von Frey monofilaments and the“up-down method”to evaluate mechanical *** treatment decreased allodynia only in female rats with spinal cord injury revealing a sexdependent *** expression profile of glutamatergic transporters(excitatory amino acid transporter 1/glutamate aspartate transporter and excitatory amino acid transporter 2/glutamate transporter-1)revealed a sexual dimorphism in the rostral,epicenter,and caudal areas of the spinal cord with a pattern of expression primarily on *** rodents showed a significantly higher level of excitatory amino acid transporter-1 expression while male rodents showed increased

关键词： allodynia central neuropathic pain EAAT-1/GLAST EAAT-2/GLT-1 glutamate transporters selective estrogen receptor modulator sexual dimorphism spinal cord injury trauma

Magnetohydrodynamic flow past a shrinking vertical sheet in a dusty hybrid nanofluid with thermal radiation

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Applied Mathematics and Mechanics(English Edition) 2022年第1期43卷 127-140页

作者： i.WAiNi A.iSHAK i.POP Fakulti Teknologi Kejuruteraan Mekanikal dan Pembuatan Universiti Teknikal Malaysia MelakaDurian Tunggal76100Malaysia Department of Mathematical Sciences Universiti Kebangsaan MalaysiaBangi43600Malaysia Department of Mathematics Babeş-Bolyai UniversityCluj-Napoca400084Romania

The magnetohydrodynamic(MHD)mixed convection flow past a shrinking vertical sheet with thermal radiation is ***,the effects of Cu-Al_(2)O_(3) nanoparticles and dust particles are *** similarity variables reduce the governing equations to the similarity equations,which are then solved *** outcome shows that,for the shrinking case,the solutions are not *** rate of heat transfer and the friction factor enlarge with increasing the values of the copper nanoparticle volume fraction as well as the magnetic ***,the assisting flow and the rise of the thermal radiation reduce these *** solutions are found,and the boundary layer separation is dependent on the mixed convection parameter.

关键词： dusty fluid hybrid nanofluid magnetohydrodynamic(MHD) mixed convection shrinking sheet thermal radiation dual solution

MHD flow and heat transfer of a hybrid nanofluid past a permeable stretching/shrinking wedge

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Applied Mathematics and Mechanics(English Edition) 2020年第3期41卷 507-520页

作者： i.WAiNi A.iSHAK i.POP Fakulti Teknologi Kejuruteraan Mekanikal dan Pembuatan Universiti Teknikal Malaysia MelakaHang Tuah JayaDurian Tunggal 76100MelakaMalaysia Department of Mathematical Sciences Faculty of Science and TechnologyUniversiti Kebangsaan MalaysiaUKM Bangi 43600SelangorMalaysia Department of Mathematics Babe¸s-Bolyai UniversityCluj-Napoca 400084Romania

The steady flow and heat transfer of a hybrid nanofluid past a permeable stretching/shrinking wedge with magnetic field and radiation effects are studied. The governing equations of the hybrid nanofluid are converted to the similarity equations by techniques of the similarity transformation. The bvp4c function that is available in MATLAB software is utilized for solving the similarity equations numerically. The numerical results are obtained for selected different values of parameters. The results discover that two solutions exist, up to a certain value of the stretching/shrinking and suction strengths. The critical value in which the solution is in existence decreases as nanoparticle volume fractions for copper and wedge angle parameter increase. it is also found that the hybrid nanofluid enhances the heat transfer rate compared with the regular nanofluid. The reduction of the heat transfer rate is observed with the increase in radiation parameter. The temporal stability analysis is performed to analyze the stability of the dual solutions, and it is revealed that only one of them is stable and physically reliable.

关键词： dual solution hybrid nanofluid stretching/shrinking wedge magnetic field radiation stability analysis

Complex Maxwell's equations

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Chinese Physics B 2013年第3期22卷 111-116页

作者： A.i.Arbab Department of Physics Faculty of ScienceUniversity of KhartoumKhartoum 11115Sudan

A unified complex model of Maxwell＇s equations is *** wave nature of the electromagnetic field vector is related to the temporal and spatial distributions and the circulation of charge and current densities.A new vacuum solution is obtained,and a new transformation under which Maxwell＇s equations are invariant is *** transformation extends ordinary gauge transformation to include charge-current as well as scalar-vector *** electric dipole moment is found to be related to the magnetic charges,and Dirac＇s quantization is found to determine an uncertainty relation expressing the indeterminacy of electric and magnetic *** generalize Maxwell＇s equations to include longitudinal waves.A formal analogy between this formulation and Dirac＇s equation is also discussed.

关键词： Maxwell's equations duality transformations magnetic charge(monopole)

Dynamic responses of a sediment-filled valley with a fluid layer subject to incident waves

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Earthquake Engineering and Engineering Vibration 2011年第2期10卷 175-185页

作者： Wen-i Liao Taipei University of Technology (NTUT)

The diffraction of elastic waves by a sedimentary valley in a homogeneous elastic half-space is studied in this paper. The sediment-filled valley is composed of a fluid layer over a soft soil deposit whose characteristics may be significant and should be carefully considered when designing long span bridges with high piers. The method of analysis adopted in the paper is to decompose the problem into an interior region and an exterior region. in the exterior region, the scattered wave fields are constructed with the linear combinations of two independent sets of Lamb＇s singular solutions, i.e., the integral solutions for two concentrated surface loads in two directions; and their derivatives are used to represent the scattered wave fields. A technique is proposed to calculate the integrals in the wave-number domain based on the method of steepest descent. For the interior region, the wave fields for the fluid layer and soft soil deposit are expressed in terms of wave functions which satisfy the equation of motion. The continuity condition at the interface of the media is satisfied in the least square sense. The effects of geometric topography, soil amplification and fluid layer subject to different types of incident harmonic plane waves are analyzed and discussed..

关键词： sedimentary valley scattered wave least square

influence of the chromium and ytterbium co-doping on the photoluminescence of zinc selenide crystals

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Journal of Rare Earths 2014年第10期32卷 938-945页

作者： i.Radevici Wihuri Physical Laboratory Department of Physics and AstronomyUniversity of Turku Faculty of Physics and Engineering Moldova State University

The luminescent properties of ZnSe, ZnSe：Cr（0.05 at.% Cr）, ZnSe：Yb（0.03 at.% Yb） and ZnSe：Cr：Yb（0.05 at.% Cr, 0.05 at.% Yb） crystals, doped during the growth process by the chemical vapor transport method, were studied within the temperature interval of 6–300 K. At the 6 K temperature in the visible spectral range 2 bands were observed： a band in the excitonic spectral region and a band of self-activated luminescence. it was shown that co-doping of zinc selenide crystals with the chromium and ytterbium led to the combination of the impurities influence on the photoluminescent properties. At the liquid helium temperature in the middle infrared range of the spectra of the ytterbium and chromium co-doped crystal a band with the maximum localized at 1.7μm was observed, which was overlapped with a complex band in the middle-iR spectral range, characteristic for the chromium doped ZnSe crystals. On the basis of obtained data an interaction mechanism of the chromium and ytterbium co-doping impurities was proposed. Guided by the existent model of the ytterbium ion incorporation in the selenide sublattice of the ZnSe crystals, an assumption about stabilization of single charged chromium ions in the zinc sublattice crystal nodes, by means of formation of the local charge compensating clusters, was made. it was assumed that the resonant energy transfer from one chromium ion to another,which led to the concentration quenching of the iR emission in the ZnSe：Cr PL spectra, would lead to the broadening of the iR emission in the spectra of ytterbium and chromium co-doped zinc selenide crystals.g

关键词： ZnSe luminescence co-doping defects Cr Yb rare earths