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Chinese physics B 2013年第10期22卷 186-191页

作者： Ali Yigit Erhan Albayrak department of physics anklrl Karatekin University department of physics Erciyes University

The bimodal random crystal field （A） effects are investigated on the phase diagrams of spin-3/2 Ising model by using the effective-field theory with correlations based on two approximations： the general van der Waerden identity and the approximated van der Waerden identity. In our approach, the crystal field is either turned on or turned off randomly for a given probability p or q = 1 -p, respectively. Then the phase diagrams are constructed on the （A,kT/J） and （p,kT/J） planes for given p and A, respectively, when the coordination number is z = 3. Furthermore, the effect of randomization of the crystal field is illustrated on the （△,kT/J） plane for p = 0.5 when z - 3,4, and 6. All these are carried out for both approximations and then the results are compared to point out the differences. In addition to the lines of second-order phase transitions, the model also exhibits first-order phase transitions and the lines of which terminate at the isolated critical points for high p values.

关键词： spin-3/2 random crystal field effective-field theory isolated critical point

Dirac equation for the Hulthén potential within the Yukawa-type tensor interaction

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Chinese physics B 2013年第1期22卷 68-76页

作者： Oktay Aydogdu Elham Maghsoodi Hassan Hassanabadi department of physics Mersin University department of physics Shahrood University of Technology

Using the Nikiforov-Uvarov （NU） method, pseudospin and spin symmetric solutions of the Dirac equation for the scalar and vector Hulthen potentials with the Yukawa-type tensor potential are obtained for an arbitrary spin-orbit coupling quantum number K. We deduce the energy eigenvalue equations and corresponding upper- and lower-spinor wave functions in both the pseudospin and spin symmetry cases. Numerical results of the energy eigenvalue equations and the upper- and lower-spinor wave functions are presented to show the effects of the external potential and particle mass parameters as well as pseudospin and spin symmetric constants on the bound-state energies and wave functions in the absence and presence of the tensor interaction.

关键词： Dirac equation Hulthen potential and Yukawa potential pseudospin and spin symmetry tensor interaction

Performance Enhancement in Dye-Sensitized Solar Cells with Composite Mixtures of TiO_2 Nanoparticles and TiO_2 Nanotubes

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Acta Metallurgica Sinica(English Letters) 2015年第3期28卷 354-361页

作者： D.Maheswari P.Venkatachalam department of physics Bharathiar University department of physics(DDE) Annamalai University

In the present investigation,a new composite nanostructured photoanodes were prepared using TiO_2 nanotubes（TNTs） with TiO_2 nanoparticles（TNPs）.TNPs were synthesized by sol-gel method,and TNTs were prepared through alkali hydrothermal ***-sensitized solar cells（DSSCs） were fabricated with different photoanodes comprising of various ratios of TNTs ＋ TNPs,synthetic indigo dye as photosensitizer,PMII（l-propyl-3-methylimidazolium iodide） as ionic liquid electrolyte and cobalt sulfide as counter *** structures and morphologies of TNPs and TNTs were analyzed through X-ray diffractometer,transmission electron microscope and scanning electron *** results of the investigation showed that the DSSC-4 made with composite photoanode structure（TNTs/TNPs）（90% of TNPs ＋ 10% of TNTs） had improved photocurrent efficiency（2.11%） than pure TNPs（1.00%） and TNT film（0.78%）.Electrochemical impedance spectra revealed that the composite TNTs/TNPs film-based DSSCs possessed the lowest charge-transfer resistances and longest electron ***,it could be concluded that the composite TNTs/TNPs photoanode facilitates the charge transport rate and enhances the efficiencies of DSSCs.

关键词： TNPs/TNTs composite mixtures Charge recombination Electron transport Photovoltaic parameters EIS analysis

High-order perturbed corrections with scaling transformation

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Chinese physics B 2008年第8期17卷 2783-2789页

作者：赵云辉赵乘麟 department of physics Shaoyang University department of physics Hunan Normal University

The performance of the so-called superconvergent quantum perturbation theory （Wenhua Hal et al2000 Phys. Rev. A 61 052105） is investigated for the case of the ground-state energy of the helium-like ions. The scaling transformation τ → τ/Z applied to the Hamiltonian of a two-electron atomic ion with a nuclear charge Z （in atomic units）. Using the improved Rayleigh-SchrSdinger perturbation theory based on the integral equation to helium-like ions in the ground states and treating the electron correlations as perturbations, we have performed a third-order perturbation calculation and obtained the second-order corrected wavefunctions consisting of a few terms and third-order energy corrections. We find that third-order and higher-order energy corrections are improved with decreasing nuclear charge. This result means that the former is quadratically integrable and the latter is physically meaningful. The improved quantum perturbation theory fits the higher-order perturbation case. This work shows that it is a development on the quantum perturbation problem of helium-like systems.

关键词： integral equation scaling transformation higher-order perturbation

Effects of interplay between metal subwavelength slits on extraordinary optical transmission

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Chinese physics B 2013年第2期22卷 239-246页

作者：魏菲菲王怀玉周云松 department of physics Capital Normal University department of physics Tsinghua University

In this paper we study the extraordinary optical transmission of one-dimensional multi-slits in an ideal metal *** transmissivity is calculated as a function of various structural *** transmissivity oscillates,with the period being just the light wavelength,as a function of the spacing between *** the number of slits increases,the transmissivity varies in one of three *** can increase,attenuate,or remain basically unchanged,depending on the spacing between *** way is in an oscillatory *** slit interaction responsible for the oscillating transmission strength that depends on slit spacing is the subject of more detailed *** interaction most intuitively manifests as a current distribution in the metal surface between *** find that this current is attenuated in an oscillating fashion from the slit corners to the center of the region between two adjacent slits,and we present a mathematical expression for its waveform.

关键词： extraordinary optical transmission metal subwavelength slits interplay between slits

Centrality dependence of pT spectra for identified hadrons in Au+Au and Cu+Cu collisions at (~SNN)^(1/2)=200 GeV

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Chinese physics C 2008年第12期32卷 976-983页

作者：王云飞邵凤兰宋军魏德明谢去病 department of physics Qufu Normal University department of physics Shandong University

The centrality dependence of transverse momentum spectra for identified hadrons at midrapidityin Au＋Au collisions at √sNN=200GeV is systematically studied in a quark combination model. The PTspectra of π^±, K^±, p（p） and A（A） in different centrality bins and the nuclear modification factors （Rcp） forthese hadrons are calculated. The centrality dependence of the average collective transverse velocity （β （r）） for the hot and dense quark matter is obtained in Au＋Au collisions, and it is applied to a relative smallerCu＋Cu collision system. The centrality dependence of PT spectra and the Rcp for π^0, Ks^0 and A in Cu-bCucollisions at √sNN = 200 GeV are well described. The results show that （β （r）〉is only a function of the numberof participants Npart and it is independent of the collision system.

关键词： relativistic high energy nucleus-nucleus collisions nuclear modification factor transverse collective flow quark combination model

Knotted picture of the whole complete quantum measurement process of quantum teleportation

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Chinese physics B 2010年第8期19卷 110-115页

作者：顾之雨钱尚武 physics department Capital Normal University physics department Peking University

Based on the previous work about the knotted pictures of quantum states, quantum logic gates and unitary transformations, this paper further gives the whole complete quantum measurement process of quantum teleportatio... 详细信息

关键词： Bell bases single particle quantum state knotted picture flip operation inversion operation composition operation

Morphology and microstructure of Ag islands of aggregated atoms on oil surfaces

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Chinese physics B 2011年第6期20卷 349-355页

作者：张初航吕能张晓飞 Saida Ajeeb 夏阿根叶高翔 department of physics Zhejiang University department of physics Hangzhou Normal University

The morphology evolution of silver islands on silicone oil surfaces is measured and the microstructure of the islands is studied. The deposited Ag atoms diffuse and aggregate on the oil surface and then Ag islands with the width of the order of 10^2-nm form. After the samples are removed from the vacuum chamber, the immediate measurement shows that the apparent Ag coverage of the total area decays with the magnitude up to （23.0±3.8）% in few minutes. In the following two hours, the samples are kept in the ambient atmosphere and several unexpected results are detected： 1） as the topological structure of the islands evolves, the total area of each island decreases gradually and the maximum decrement measured is around 20%; 2） if an island breaks and becomes two small pieces, the total area decreases obviously; 3） however, if two small islands meet and stick together, a sudden increment of the total area is observed. These phenomena, mirroring the evolution process of the island microstructure, are resulted from both the diffusion of the atoms and the combination of the defects inside the islands.

关键词： liquid substrate island microstructure morphology

Kac-Moody-Virasoro symmetry algebra of a (2+1)-dimensional bilinear system

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Chinese physics B 2008年第3期17卷 747-753页

作者：李金花楼森岳 department of physics Ningbo University department of physics Shanghai Jiaotong University

Based on some known facts of integrable models, this paper proposes a new （2＋1）-dimensional bilinear model equation. By virtue of the formal series symmetry approach, the new model is proved to be integrable because of the existence of the higher order symmetries. The Lie point symmetries of the model constitute an infinite dimensional Kac- Moody Virasoro symmetry algebra. Making use of the infinite Lie point symmetries, the possible symmetry reductions of the model are also studied

关键词： general symmetries Kac-Moody Virasoro symmetry algebra symmetry reduction

Bound states of the Dirac equation with position-dependent mass for the Eckart potential

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Chinese physics B 2013年第1期22卷 62-67页

作者： Bahar M. K. Yasuk F. department of physics Erciyes University department of physics Karamanoglu Mehmetbey University

Studying with the asymptotic iteration method, we present approximate solutions of the Dirac equation for the Eckart potential in the case of position-dependent mass. The centrifugal term is approximated by an exponen... 详细信息

关键词： Dirac equation position-dependent mass Eckart potential asymptotic iteration method