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effects of the partial replacement of La by m(m=Ce,Ca and sr) in La_(2-x)m_xCuO_4 perovskites on catalysis of the water-gas shift reaction

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Journal of Natural Gas Chemistry 2010年第6期19卷 567-574页

作者： s.s.maluf e.m.Assaf Institute de Química de so Carlos Universidade de So PauloAv.Trabalhador Socarlense400 So CarlosSP 13560-970Brazil

The performance of La2-x m x CuO4 perovskites （where m=Ce,Ca or sr） as catalysts for the water-gas shift reaction was investigated at 290℃ and 360℃.The catalysts were characterized by eDs,XRD,N2 adsorption-desorption,XPs and *** XRD results showed that all the perovskites exhibited a single phase （the presence of perovskite structure）,suggesting the incorporation of metals in the perovskite *** XPs and XANes results showed the presence of Cu2＋ on the *** perovskites that exhibited the best catalytic performance were La 2 x Ce x CuO 4 perovskites,with CO conversions of 85% 90%.moreover,these perovskites have higher surface areas and larger amounts of Cu on the *** Ce has a higher filled energy level than the other metals,increasing the energy of the valence band of Ce and providing more electrons for the ***,the La1.80Ca0.20CuO4 perovskite showed a good catalytic performance.

关键词： perovskites water-gas shift reaction lanthanum copper calcium cerium strontium

modelling, parameter estimation and assessment of partial shading conditions of photovoltaic modules

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Journal of modern Power systems and Clean energy 2019年第1期7卷 55-64页

作者： s.LYDeN m.e.HAQUe school of engineering University of Tasmania school of engineering Deakin University

This paper proposes a method for assessing the effect that different features of partial shading conditions(PsC) may have on the operation of a photovoltaic(PV)*** studies, based on an experimentally validated model of a PV system, are used to assess the influence of *** classifications of PsC are defined based on the timescale of their influence on the irradiance experienced by the PV module and the relative location of the voltage at which the global maximum power point occurs is *** case studies are presented to illustrate the application of the proposed PsC assessment *** results have implications for the design of future maximum power point tracking methods.

关键词： Photovoltaic modelling Partial shading maximum power point

Landau damping in a dipolar Bose–Fermi mixture in the Bose–einstein condensation(BeC) limit

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Chinese Physics B 2016年第12期25卷 367-376页

作者： s m moniri H Yavari e Darsheshdar Department of Physics University of Isfahan

By using a mean-field approximation which describes the coupled oscillations of condensate and noncondensate atoms in the collisionless regime, Landau damping in a dilute dipolar Bose-Fermi mixture in the BeC limit where Fermi superfluid is treated as tightly bounded molecules, is investigated. In the case of a uniform quasi-two-dimensional （2D） case, the results for the Landau damping due to the Bose-Fermi interaction are obtained at low and high temperatures. It is shown that at low temperatures, the Landau damping rate is exponentially suppressed. By increasing the strength of dipolar interaction, and the energy of boson quasiparticles, Landau damping is suppressed over a broader temperature range.

关键词： Landau damping mixtures of Bose and Fermi superfluids dipole-dipole interaction

exact solutions of Nonlinear evolution equations in mathematical Physics Using the modified simple equation method

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Chinese Physics Letters 2012年第6期29卷 1-4页

作者： e.m.e.Zayed s.A.Hoda Ibrahim Department of mathematics Faculty of ScienceZagazig UniversityP.O.Box 44519ZagazigEgypt

The modified simple equation method is employed to construct the exact solutions involving parameters of nonlinear evolution equations via the (1+1)-dimensional modified KdV equation,and the (1+1)-dimensional reaction-diffusion *** these parameters are taken to be special values,the solitary wave solutions are derived from the exact *** is shown that the proposed method provides a more powerful mathematical tool for solving nonlinear evolution equations in mathematical physics.

关键词： equation. exact equation

La_(2-x)CexCu_(1-y)Zn_yO_4 perovskites for high temperature water-gas shift reaction

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Journal of Natural Gas Chemistry 2009年第2期18卷 131-138页

作者： s. s. maluf e. m. Assaf Instituto de Química de so Carlos Universidade de So Paulo Av. Trabalhador Socarlense400 So Carlos SP 13560-970 Brazil

The performance of La2-xCexCu1-yZnyO4 perovskites as catalysts for the high temperature water-gas shift reaction （HT-WGsR） was investigated. The catalysts were characterized by eDs, XRD, BeT surface area, TPR, and XANes. The results showed that all the perovskites exhibited the La2CuO4 orthorhombic structure, so the Pechini method is suitable for the preparation of pure perovskite. However, the La1.90Ce0.10CuO4 perovskite alone, when calcined at 350/700℃, also showed a （La0.935Ce0.065）2CuO4 perovskite with tetragonal struc- ture, which produced a surface area higher than the other perovskites. The perovskites that exhibited the best catalytic performance were those calcined at 350/700℃ and, among these, La1.90Ce0.10CuO4 was outstanding, probably because of the high surface area associated with the presence of the （La0.935Ce0.065）2CuO4 perovskite with tetragonal structure and orthorhombic La2CuO4 phase.

关键词： perovskite shift reaction lanthanum copper cerium

structural and magnetic properties of turmeric functionalized CoFe_2O_4 nanocomposite powder

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Chinese Physics B 2016年第10期25卷 418-422页

作者： e mehran s Farjami shayesteh m sheykhan Nanostructures Laboratory Department of Physics University of Guilan Department of Chemistry University of Guilan

The structural and magnetic properties of the synthesized pure and functionalized CoFe2O4magnetic nanoparticles(NPs) are studied by analyzing the results from the x-ray diffraction(XRD), transmission electron microscopy(Tem), FT–IR spectroscopy, thermogravimetry(TG), and vibrating sample magnetometer(Vsm). To extract the structure and lattice parameters from the XRD analysis results, we first apply the pseudo-Voigt model function to the experimental data obtained from XRD analysis and then the Rietveld algorithm is used in order to optimize the model function to estimate the true intensity values. Our simulated intensities are in good agreement with the experimental peaks, therefore, all structural parameters such as crystallite size and lattice constant are achieved through this simulation. magnetic analysis reveals that the synthesized functionalized NPs have a saturation magnetization almost equal to that of pure nanoparticles(PNPs). It is also found that the presence of the turmeric causes a small reduction in coercivity of the functionalized NPs in comparison with PNP. Our TGA and FTIR results show that the turmeric is bonded very well to the surface of the NPs. so it can be inferred that a nancomposite(NC) powder of turmeric and nanoparticles is produced. As an application, the anti-arsenic characteristic of turmeric makes the synthesized functionalized NPs or NC powder a good candidate for arsenic removal from polluted industrial waste water.

关键词： cobalt ferrite nanoparticles structural properties magnetic properties turmeric

effect of weak measurement on quantum correlations

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Chinese Physics B 2020年第11期29卷 174-181页

作者： L Jebli m Amzioug s e ennadifi N Habiballah m Nassik ePTHe Department of PhysicsFaculty of SciencesIbn Zohr UniversityAgadirMorocco Faculty of Applied sciences Ibn Zohr UniversityAit-MelloulMorocco Abdus salam International Center for Theoretical Physics Strada Costiera11 I-34151TriesteItaly LHeP-ms Department of PhysicsFaculty of Science Mohammed V UniversityRabatMorocco Department of Physics Ecole Normale Sup´eieure(ENS)Mohammed V UniversityRabatMorocco

We investigate the local quantum uncertainty(LQU)in weak *** expression of weak LQU is explicitly ***,we consider some cases of three special X states,Werner state,circulant two-qubit states,and Heisenberg model via L... 详细信息

关键词： local quantum uncertainty weak measurement weak local quantum uncertainty

exact solutions of Kolmogorov-Petrovskii-Piskunov equation Using the modified simple equation method

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Acta mathematicae Applicatae sinica 2014年第3期30卷 749-754页

作者： e.m.e.Zayed s.A.Hoda Ibrahim mathematics Department Faculty of ScienceZagazig University

The modified simple equation method is employed to find the exact solutions of the nonlinear Kolmogorov-Petrovskii-Piskunov （KPP） equation. When certain parameters of the equations are chosen to be special values, the solitary wave solutions are derived from the exact solutions. It is shown that the modified simple equation method provides an effective and powerful mathematical tool for solving nonlinear evolution equations in mathematical physics.

关键词： modified simple equation method Kolmogorov-Petrovskii-Piskunov equation exact solutions solitary wave solutions

spinless particles in the field of unequal scalar vector Yukawa potentials

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Chinese Physics B 2013年第4期22卷 81-86页

作者： m.Hamzavi s.m.Ikhdair K.e.Thylwe Department of science and engineering Abhar Branch Islamic Azad University Abhar Iran Department of electrical and electronic engineering Near East University 922022 Nicosia North Cyprus Mersin 10 Turkey Department of Physics Faculty of Science An-Najah National University Nablus West Bank Palestine KTH-mechanics Royal Institute of Technology S-100 44 Stockholm Sweden

We present analytical bound state solutions of the spin-zero Klein–Gordon （KG） particles in the field of unequal mix-ture of scalar and vector Yukawa potentials within the framework of the approximation scheme to the centrifugal potential term for any arbitrary l-state. The approximate energy eigenvalues and unnormalized wave functions are obtained in closed forms using a simple shortcut of the Nikiforov–Uvarov （NU） method. Further, we solve the KG–Yukawa problem for its exact numerical energy eigenvalues via the amplitude phase （AP） method to test the accuracy of the present solutions found by using the NU method. Our numerical tests using energy calculations demonstrate the existence of inter-dimensional degeneracy amongst the energy states of the KG–Yukawa problem. The dependence of the energy on the dimension D is numerically discussed for spatial dimensions D = 2–6.

关键词： Klein–Gordon equation Yukawa potential D-dimensional space Nikiforov–Uvarov and amplitude phase methods