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Structure and Thermal Parameters of Ni_(20)Pd_(80) Alloy

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Journal of Materials Science & Technology 2009年第2期25卷 208-210页

作者： S. Ahmad A.B. Ziya A. Aziz Z.I. Zafar department of Physics Bahauddin Zakariya University department of Chemistry Bahauddin Zakariya University

The structure and thermal parameters of Ni20Pd80 alloy were studied by X-ray diffraction（XRD）. The diffraction experiments performed in the temperature range of 308-1100 K revealed that the alloy formed a face centered cubic （fcc） Al-type structure. The temperature dependence of the lattice parameters was investigated by using the Bragg line displacement method showing that the lattice parameter increases with the increase of temperature. The mean linear thermal expansion （MLTE（%））, coefficient of thermal expansion （CTE, α）, the characteristic Debye temperature （（θD） and mean square amplitudes of vibration were determined from XRD data. The value of Debye temperature was found to be 253 K. It was found that temperature factor was independent of the static displacements.

关键词： Alloys Structure Thermal parameters X-ray diffraction (XRD)

Compact-like discrete breather and its stability in a discrete monatomic Klein-Gordon chain

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Chinese Physics B 2008年第12期17卷 4614-4618页

作者：徐权田强 department of Physics Daqing Normal University department of Physics Beijing Normal University

This paper studies a discrete one-dimensional monatomic Klein Gordon chain with only quartic nearest-neighbour interactions, in which the compact-like discrete breathers can be explicitly constructed by an exact separation of their time and space dependence. Introducing the trying method, it proves that compact-like discrete breathers exist in this nonlinear system. It also discusses the linear stability of the compact-like discrete breathers, when the coefficient （β） of quartic on-site potential and the coupling constant （K4） of quartic interactive potential satisfy the given conditions, they are linearly stable.

关键词： compact-like discrete breather Klein Gordon chain linear stability

Fabrication of grating-like polystyrene latex monolayer structure as three-dimensional calibration standards for scanning probe microscope

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Chinese Physics B 2009年第3期18卷 997-1001页

作者：朱国栋曾志刚国璋杜强国严学俭 department of Materials Science Fudan University department of Macromolecular Science Fudan University

This paper illuminates the preparation of grating-like polystyrene latex monolayer structure, which can minimize the effects of the size deviation of spheres and the defect transfer on the accuracy as calibration samples for micro-scopes. The latex films are grown on freshly cleaved mica substrates by vertical deposition method. The concentration dependence of the structure and the topography of latex films is characterized by optical microscope, ultraviolet- visible transmission spectrum and scanning probe microscope. The origination of such a grating-like structure is also discussed.

关键词： polystyrene spheres scanning probe microscope grating-like structure calibration samrile

Suppressing the disturbance in the transmission spectrum of Glan-Thompson-type prism polarizers

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Chinese Optics Letters 2010年第4期8卷 428-430页

作者：李红霞范吉阳苏富芳吴福全祝世宁 department of Applied Physics Nanjing University of Science and Technology department of Physics Nanjing University department of Physics Southeast University Laser Research Institute Qufu Normal University department of Physics Nanjing University

We analyze the random disturbance in the transmission of light through a spinning Glan-Thompsontype prism *** disturbance makes the dependence of the transmission on the rotation angle significantly deviates from the Malus cosine-squared law and severely spoils the output light *** vibration of the polarizer as it rotates combing the multi-beam-interference effect raises the disturbance. Further analysis reveals the sensitive dependence of the disturbance on the composing material of the prism gap,and the appropriate selection of such material can make the disturbance minimize to very desirable *** model results show quite good agreement with experiments.

关键词： Light sources Optical instruments Prisms

Phase diagrams in mixed spin-3/2 and spin-2 Ising system with two alternative layers within the effective-field theory

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Chinese Physics B 2011年第6期20卷 112-124页

作者： Bayram Deviren Yasin Polat Mustafa Keskin department of Physics Nevsehir University Institute of Science Erciyes University department of Physics Erciyes University

The phase diagrams in the mixed spin-3/2 and spin-2 Ising system with two alternative layers on a honeycomb lattice are investigated and discussed by the use of the effective-field theory with correlations. The interaction of the nearest-neighbour spins of each layer is taken to be positive （ferromagnetic interaction） and the interaction of the adjacent spins of the nearest-neighbour layers is considered to be either positive or negative （ferromagnetic or antiferromagnetic interaction）. The temperature dependence of the layer magnetizations of the system is examined to characterize the nature （continuous or discontinuous） of the phase transitions and obtain the phase transition temperatures. The system exhibits both second- and first-order phase transitions besides triple point （TP）, critical end point （E）, multicritical point （A）, isolated critical point （C） and reentrant behaviour depending on the interaction parameters. We have also studied the temperature dependence of the total magnetization to find the compensation points, as well as to determine the type of behaviour, and N-type behaviour in Neel classification nomenclature existing in the system. The phase diagrams are constructed in eight different planes and it is found that the system also presents the compensation phenomena depending on the sign of the bilinear exchange interactions.

关键词： mixed spin-3/2 and spin-2 Ising system effective-field theory compensation phenomena phase diagrams

Energy transfer and correlation dynamics in a three-quasi-spin-pigment system

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Chinese Physics B 2013年第5期22卷 441-448页

作者：张银苹李宏荣方爱萍陈浩李福利 department of Applied Physics Xi'an Jiaotong University department of Applied Physics Xi’an Jiaotong University

In this paper, the effects of quantum and classical correlations on the excitation energy transfer in a three-quasi- spin-pigment system are investigated. We first study the dependence of the energy transfer efficiency on various initial correlations of the donor pigments, and find that the initial concurrence is crucial to the efficiency no matter whether the initial states are pure or mixed. We then demonstrate the dynamics of correlations of the system and observe the appearance of sudden death of quantum correlations in the donor pigments. The relation between the energy transfer efficiency and the dynamics of correlations in the donor pigments is also discussed.

关键词： energy transfer correlation quasi-spin-pigment system

Rapidity dependence of hadron p_T spectra in central Au+Au collisions at s_(NN)～(1/2)=200 GeV

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Chinese Physics C 2009年第6期33卷 481-486页

作者：邵凤兰宋军谢去病 department of Physics Qufu Normal University department of Physics Shandong University

The transverse momentum spectra for identified hadrons at different rapidities in central Au＋Au collisions at √^SNN= 200 GeV are studied in a quark combination model. The results for PT spectra of π^±, K^±, p（p^-） and for the p/π ratios in a broader PT range at midrapidity agree well with the data. The transverse momentum spectra of pions, protons and antiprotons at various rapidities y - 1, η= 2.2 and y ≈ 3.2 are calculated and compared with the data.

关键词： relativistic heavy ion collisions hadronization quark combination

Molecular Dynamics Studies of the Kinetics of Phase Changes in Clusters IV:Crystal Nucleation from Molten (NaCl)_(256) and (NaCl)_(500) Clusters

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Chinese Journal of Chemistry 2003年第12期21卷 1543-1552页

作者：李小华黄锦凡 department of Chemistry Nanjing Xiaozhuang College department of Chemistry University of Michigan

Molecular dynamics computer simulation based on the Born-Mayer-Huggins potential function has been carried out to study the effects of cluster size and temperature on the nucleation rate of sodium chloride clusters in the temperature range of 580 K to 630 K. Clusters with 256 and 500 NaCl molecules have been studied and the results have been compared with those obtained from 108 molecule clusters. The melting point (MP) of the clusters were observed to increase with the size of the clusters and can be well described by a linear equation MP=1107(37)-1229(23)N -1/3 (N is the number of molecules in the cluster). The nucleation rate was found to decrease with increasing the cluster size or temperature. Various nucleation theories have been used to interpret the nucleation rates obtained from this molecular dynamics simulation. It is possible to use a constant diffuse interface thickness to interpret the nucleation rate from the diffuse interface theory in the temperature range of this study. However,the interfacial free energy estimated from classical nucleation theory and diffuse interface theory increases too fast with increasing the temperature while that from Gran-Gunton theory does not change with changing temperatures. The sizes of critical nuclei estimated from all the theories are smaller than those estimated from our simulations.

关键词： sodium chloride crystal nucleation rate interfacial free energy size dependence temperature dependence

Application of ferrate(VI) in the treatment of industrial wastes containing metal-complexed cyanides : A green treatment

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Journal of Environmental Sciences 2009年第10期21卷 1347-1352页

作者： SEUNG-MOK Lee DIWAKAR Tiwari department of Environmental Engineering Kwandong University department of Chemistry School of Physical Sciences Mizoram University

Ferrate（VI） was employed for the oxidation of cyanide （CN） and simultaneous removal of copper or nickel in the mixed/complexed systems of CN-Cu, CN-Ni, or CN-Cu-Ni. The degradation of CN （1.00 mmol/L） and removal of Cu （0.095 mmol/L） were investigated as a function of Fe（Ⅵ） doses from 0.3-2.00 mmol/L at pH 10.0. It was found that Fe（Ⅵ） could readily oxidize CN and the reduction of Fe（Ⅵ） into Fe（Ⅲ） might serve efficiently for the removal of free copper ions. The increase in Fe（Ⅵ） dose apparently favoured the CN oxidation as well as Cu removal. Moreover, the pH dependence study （pH 10.0-13.0） revealed that the oxidation of CN was almost unaffected in the studied pH range （10.0-13.0）, however, the maximum removal efficiency of Cu was obtained at pH 13.0. Similarly, treatment was carded out for CN-Ni system having the initial Ni concentration of 0.170 mmol/L and CN concentration of 1.00 mmol with Fe（Ⅵ） dose 2.00 mmol at various pH values （10.0-12.0）. Results showed a partial oxidation of CN and partial removal of Ni. It can be observed that Fe（Ⅵ） can partially degrade the CN-Ni complex in this pH range. Further, Fe（Ⅵ） was applied for the treatment of simulated industrial waste/effluent waters treatment containing CN, Cu, and Ni.

关键词： cyanide metal-complexed cyanide oxidation copper nickel ferrate(Ⅵ)