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Application of asymptotic iteration method to a deformed well problem

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Chinese Physics B 2016年第3期25卷 40-44页

作者： Hakan Ciftci H f Kisoglu Gazi Universitesi Fen FakultesiFizik Bolumu 06500 Teknikokullar AnkaraTurkiye Maritime faculty Department of Basic SciencesMersin UniversityMersinTurkey

The asymptotic iteration method （AIM） is used to obtain the quasi-exact solutions of the Schr6dinger equation with a deformed well potential. for arbitrary potential parameters, a numerical aspect of AIM is also applied to obtain highly accurate energy eigenvalues. Additionally, the perturbation expansion, based on the AIM approach, is utilized to obtain simple analytic expressions for the energy eigenvalues.

关键词： asymptotic iteration method quasi-exact solutions perturbation method approximate solutions

Nonlinear Propagation of Positron-Acoustic Periodic Travelling Waves in a Magnetoplasma with Superthermal Electrons and Positrons

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Chinese Physics Letters 2017年第6期34卷 70-74页

作者： E.f.EL-Shamy Department of Physics College of ScienceKing Khalid University Department of Physics Faculty of ScienceDamietta University

The nonlinear propagation of positron acoustic periodic （PAP） travelling waves in a magnetoplasma composed of dynamic cold positrons, superthermal kappa distributed hot positrons and electrons, and stationary positive ions is examined. The reductive perturbation technique is employed to derive a nonlinear Zakharov Kuznetsov equation that governs the essential features of nonlinear PAP travelling waves. Moreover, the bifurcation theory is used to investigate the propagation of nonlinear PAP periodic travelling wave solutions. It is found that kappa distributed hot positrons and electrons provide only the possibility of existence of nonlinear compressive PAP travelling waves. It is observed that the superthermality of hot positrons, the concentrations of superthermal electrons and positrons, the positron cyclotron frequency, the direction cosines of wave vector k along the z-axis, and the concentration of ions play pivotal roles in the nonlinear propagation of PAP travelling waves. Tile present investigation may be used to understand the formation of PAP structures in the space and laboratory plasmas with superthermal hot positrons and electrons.

关键词： Nonlinear Propagation of Positron-Acoustic Periodic Travelling Waves in a Magnetoplasma with Superthermal Electrons and Positrons

Pair bonds during the annual cycle of a long-distance migrant,the Arctic Tern(Sterna paradisaea)

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Avian Research 2021年第3期12卷 346-353页

作者： Chris P.f.Redfern School of Natural&Environmental Sciences Newcastle UniversityNE24HH&Natural History Society of NorthumbriaGreat North Museum:HancockNewcastle upon Tyne NE24PTUK

Background:The extent to which pairs remain together during the annual cycle is a key question in the behav-ioural ecology of migratory *** a few species migrate and winter as family units,for most the extent to which breeding partners associate in the non-breeding season is *** Arctic Tern(Sterna paradisaea)has one of the longest migrations of any species,and the aim of this study was to establish whether or not partners remain together after ***:Leg-mounted geolocators were fitted to breeding pairs of Arctic Terns nesting on the farne Islands,North-umberland,*** devices were recovered for analysis the following ***:Analysis of data for the six pairs which returned the following year showed that partners departed from the colony at different times after breeding and migrated independently to different Antarctic *** also departed from the Antarctic and turned to the breeding colony *** third of the pairs divorced on ***:for long-distance migrants reliant on unpredictable foraging opportunities,it may not be viable to remain as pairs away from the breeding *** in arrival times at the breeding colony may maximise the chance of retaining a familiar partner,but could be affected by environmental factors in wintering areas or along migration routes.

关键词： Arctic Tern Migration Pair-bond Partner association

Teleportation of unknown states of a qubit and a single-mode field in strong coupling regime without Bell-state measurement

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Communications in Theoretical Physics 2023年第2期75卷 73-79页

作者： f Jahanbakhsh M K Tavassoly Optics and Laser Group Faculty of PhysicsYazd UniversityYazd 89195-741Iran

In this paper,we develop the teleportation scheme in[Zheng in Phys Rev A 69,064302,2004],in the sense that,we work in the strong atom-field coupling regime wherein the rotating wave approximation(RWA)is no longer *** achieve the purpose,a scheme consisting of a qubit interacting with a single-mode quantized field is described via the Rabi model(counter rotation terms are taken into account).Our first aim is to teleport an unknown atomic state of a qubit(which interacts with the quantized field in a cavity)to a second qubit(exists in another distant cavity field),beyond the RWA and without the Bell-state measurement *** the continuation,in a similar way,we teleport an unknown state of a single-mode field *** fact,it is shown that,in this regime,after applying some particular conditions,containing the interaction time of atom-field in the cavities,adjusting the involved frequencies,as well as the atom-field coupling in the model,if a proper measurement is performed on the state of the first qubit(the related field in the cavity),the unknown states of the qubit(field)can be teleported from the first qubit(cavity field)to the second qubit(cavity field),*** show that in both considered cases,the teleportation protocol is successfully performed with the maximum possible fidelity,1,and the acceptable success probability,0.25.

关键词： strong atom-field coupling Rabi model quantum teleportation success probability fidelity

Enhanced Mechanical Properties of friction Stir Welded 5083Al-H19 Joints with Additional Water Cooling

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Journal of Materials Science & Technology 2017年第9期33卷 1009-1014页

作者： B.B.Wang f.f.Chen f.Liu W.G.Wang P.Xue Z.Y.Ma School of Mechanical Engineering Liaoning Shihua University Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of Sciences

3-mm-thick 5083Al-H19 rolled plates were friction stir welded(fSW) at tool rotation rates of 800 and200 rpm with and without additional water cooling. With decreasing the rotation rate and applying water cooling, softening in the fSW joint was significantly reduced. At a low rotation rate of 200 rpm with additional water cooling, almost no obvious softening was observed in the fSW joint, and therefore a fSW5083Al-H19 joint with nearly equal strength to the base material(BM) was obtained. furthermore, the grains in the nugget zone were considerably refined with reducing the heat input and ultrafine equiaxed grains of about 800 nm were obtained in the lowest heat input condition. This work provides an effective method to achieve high property fSW joints of precipitate-hardened and work-hardened Al alloys.

关键词： friction stir welding Aluminum alloy Water cooling Microstructure Mechanical property

High Strain Rate Superplasticity in a Micro-grained Al-Mg-Sc Alloy with Predominant High Angle Grain Boundaries

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Journal of Materials Science & Technology 2012年第11期28卷 1025-1030页

作者： f. C. Liu Z.Y. Ma f. C. Zhang Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of SciencesShenyang 110016 China State Key Laboratory of Metastable Materials Science and Technology Yanshan University Qinhuangdao 066004China

friction stir processing （fSP） was applied to extruded AI-Mg-Sc alloy to produce fine-grained microstructure with a grain size of 2.2μm. Electron backscatter diffraction （EBSD） result showed that the grain boundary misorientation distribution was very close to a random grain assembly for randomly oriented cubes. Super- plastic investigations in the temperature range of 425-500 ℃ and strain rate range of 1x100^-2-1x10 s^-1 showed that a maximum elongation of 1500% was achieved at 475 ℃ and a high strain rate of 1x100^-2-1x10 s^-1. The fSP AI-Mg-Sc exhibited enhanced superplastic deformation kinetics compared to that predicted by the constitutive relationship for superplasticity in fine-grained aluminum alloys. The origin for enhanced superplas- tic deformation kinetics in the fSP alloy can be attributed to its high fraction of high angle grain boundaries （HAGBs）. The analyses of the superplastic data and scanning electron microscopy （SEM） examinations on the surfaces of deformed specimens indicated that grain boundary sliding is the main superplastic deformation mechanism for the fSP AI-Mg-Sc alloy.

关键词： Superplasticity friction stir processing Aluminum Microstructure friction stir welding

Beam steering in planar photonic crystal based on its anomalous dispersive properties

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第1期7卷 45-54页

作者： WU Li-jun MAZILU M GALLETJ．f． KRAUSST．f． The Ultrafast Photonics Collaboration School of Physics ＆ Astronomy University of St Andrews St. Andrews. Fife KY16 9SS. Scotland UK Department of Physics. Hong Kong University of Science and Technology. Hong Kong China

We utilize the anomalous dispersion of planar photonic crystals near the dielectric band edge to control the wavelength-dependent propagation of light. We typically observe an angular swing of up to 10°as the input wavelength is changed from 1290 nm to 1310 rim, which signifies an angular dispersion of 0.5°/am （＂Superprism＂ phenomenon）. Such a strong angular dispersion is of the order required for WDM systems. By tuning the incident angle, light beams with up to 20° divergence were collimated over a 25 nm （1285 nm to 1310 nm） bandwidth using a triangular lattice （＂Supercollimator＂ phenomenon）. The wavelength collimating range can be extended from 25 nm to 40 nm by changing the lattice from triangular to square. These two devices can be realized in the same configuration, simply by tuning the wavelength. Sources of loss are discussed.

关键词： Planar photonic crystals Superprism Supercollimator Anomalous dispersive properties

fAB MS of Permethylated L-β-Aspartamido-Carbohydrates

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Chemical Research in Chinese Universities 1998年第2期14卷 52-54,56-58页

作者： WANG Tsong-hui CHEN T.f. Barofsky D.f. Department of Instrumental Analysis Institute of Forensic ScienceBeijing100038 Department of Agricultural Chemistry Oregon State UniversityCorvallisOregon 97331USA

Native glycopeptides are suitable to fAB mass spectrometric analysis due to their high polarity, low volatility and large molecular size. The deficiency in the fAB spectra of glycopeptides is the limited number of peaks and the low abundances of fragments. In order to obtain the information of carbohydrate sequence the permethylation of carbohydrate, a well known method, is recommended here. The L β aspartamido carbohydrate from chicken egg albumin was chosen as the model compound of glycopeptides. Our experiments showed obvious carbohydrate sequence in the spectra of permethylated aspartamido carbohydrates. The key conditions to perform the method are the methylation reagent and purification process for the permethylated derivatives.

关键词： Glycopeptide Ovalbumin Permethylation fABMS

IN SITU PROCESSING Of Al_(2)O_(3) WHISKERS REINfORCED Ti-Al INTERMETALLIC COMPOSITES

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Acta Metallurgica Sinica(English Letters) 2006年第6期19卷 432-440页

作者： f.Wang Z.K.fan J.f.Zhu School of Materials Science and Engineering Xi’an University of TechnologyXi’an 710048China School of Materials Science and Engineering Shaanxi University of Science and TechnologyXianyang 712081China

In situ Al2O3 whiskers reinforced Ti-Al intermetallic composites were fabricated at ~1200℃ by reaction sintering of cold-consolidated fillets consisting mainly of Ti, Al, and different additives. The phases and microstructures of the sintered composites were characterized using X-ray diffraction (XRD) and scanning electron microscopy (SEM) coupled with energy dispersive spectroscopy (EDS). The process of synthesis was investigated using differential thermal analysis (DTA). The effects of processing parameters and additives on the microstructures of the composites and the development of whisker were examined. It is found that the morphology of the whisker is strongly influenced by the additives, the exothermal reaction process, and the processing parameters.

关键词： in situ Al2O3 whisker Ti-Al intermetallic composite additive reaction process