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The nonrelativistic oscillator strength of a hyperbolic-type potential

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Chinese Physics B 2013年第6期22卷 105-109页

作者： H.Hassanabadi s.Zarrinkamar B.H.Yazarloo Department of Basic sciences Shahrood BranchIslamic Azad UniversityShahroodIran Department of Basic sciences Garmsar BranchIslamic Azad UniversityGarmsarIran

We consider the D-dimensional schrsdinger equation under the hyperbolic potential V0（1 -coth（ar））＋ 171 （1 - coth（ar））2. Using a Pekeris-type approximation, the approximate analytical solutions of the problem are obtained via the supersymmetric quantum mechanics. The behaviors of energy eigenvalues versus dimension are discussed for various quantum numbers. Useful expectation values as well as the oscillator strength are obtained.

关键词： schroedinger equation D-dimensional space hyperbolic potential supersymmetry quantum me-chanics oscillator strength

Production of neutron-rich exotic nuclei in projectile fragmentation at Fermi energies

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Nuclear science and Techniques 2017年第2期28卷 18-23页

作者： R.Ogul N.Buyukcizmeci A.Ergun A.s.Botvina Department of Physics University of Selcuk ITP and Frankfurt Institute for Advanced studies J.W.Goethe University Institute for Nuclear Research Russian Academy of Sciences

Isotopic fragment yields of projectile fragmentation in peripheral collisions of^(86)Kr on^(124;112)sn and the mean neutron-to-proton ratios of the fragments are calculated, theoretically, within the ensemble approach of statistical multifragmentation model. Obtained data are compared to the experimental cross-section measurements for the projectile-like fragmentation in the reaction of 25 Me V/nucleon^(86)Kr+^(124;112)sn at Texas A&M *** show the enhancement in the production of neutronrich isotopes close to the projectile as observed in the experiments. We also demonstrate the universality of the limitation of the excitation energy induced in the projectile residues.

关键词： Projectile fragmentation Peripheral collisions Isotope productions Universality

A sufficient Condition for Kernel Perfectness of a Digraph in Terms of semikernels Modulo F

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Acta Mathematica sinica,English series 2012年第2期28卷 349-356页

作者： Camino BALBUENA Hortensia GALEANA-sNCHEZ Mucuy-kak GUEVARA Departament de Matematica Aplicada III Universitat Politècnica de Catalunya Instituto de Matemáticas Universidad Nacional Autónoma de México rea de la Investigación Científica Circuito Exterior Ciudad Universitaria Facultad de Ciencias Universidad Nacional Autónoma de México Universidad 3000 Circuito Exterior s/n Ciudad Universitaria

A kernel of a directed graph is a set of vertices which is both independent and absorbent. And a digraph is said to be kernel perfect if and only if any induced subdigraph has a kernel. Given a set of arcs F, a semikernel s modulo F is an independent set such that if some sz-arc is not in F, then there exists a zs-arc. A sufficient condition on the digraph is given in terms of semikernel modulo F in order to guarantee that a digraph is kernel perfect. To do that we give a characterization of kernel perfectness which is a generalization of a previous result given by Neumann-Lara [seminucleos de una digrafica. Anales del Instituto de Matematicas 2, Universidad Nacional Autsnoma de Mexico, 1971]. And moreover, we show by means of an example that our result is independent of previous known sufficient conditions.

关键词： Digraphs. kernel kernel-nerfect semikernel

Cracking susceptibility After Post-Weld Heat Treatment in Haynes 282 Nickel Based superalloy

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Acta Metallurgica sinica(English Letters) 2013年第6期26卷 747-753页

作者： L.O.Osoba A.K.Khan s.O.Adeosun Department of Metallurgical and Materials Engineering University of Lagos Department of Mechanical and Manufacturing Engineering University of Manitoba

This paper presents a study of the standard post-weld heat treatment （PWHT） behaviour of autogenous laser welded γ＇ age-hardenable precipitation strengthened nickel based superalloy Haynes 282 （HY 282）. The study involves a careful and detailed microstructural characterisation as well as an analysis of the weld cracking susceptibility during welding and Gleeble thermo-mechanical physical simulation. Various factors that could influence post-weld cracking in superalloys weld were experimentally examined. Our microstructural exami- nation of the as-solution heat treated （sHTed） material and the thermo-mechanically refined grain material shows that intergranular heat affected zone （HAZ） cracking is observable in only the as-welded sHTed material. There was no indication of post-weld heat treatment cracking in all welded materials. Our conclusion, in this study, is that the chemistry of superalloy HY 282 which aids the preclusion/formation of deleterious so- lidification microconstituents during welding as well as its relatively slow aging kinetics enhances its resistance to PWHT cracking.

关键词： Cracking Microstructure Analysis Nickel based superalloy

Composition, structure and diversity characterization of dry tropical forest of Chhattisgarh using satellite data

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Journal of Forestry Research 2014年第4期25卷 819-825页

作者： Tarun Thakur s.L. swamy Ajit singh Nain Department of Forestry Indira Gandhi Agricultural University (IGAU) Raipur Chhattisgarh India

The purpose of this study was to characterize the land use, vegetation structure, and diversity in the Barnowpara sanctuary, Raipur district, Chhattisgarh, India through the use of satellite remote sensing and GIs. Land cover and vegetation were spatially analyzed by digitally classifying IRs 1D LIss III satellite data using a maximum likelihood algorithm. Later, the variations in structure and diversity in different forest types and classes were quantified by adopting quadratic sampling proce- dures. Nine land-cover types were delineated： teak forest, dense mixed forest, degraded mixed forest, sal mixed forest, open mixed forest, young teak plantation, grasslands, agriculture, habitation, and water bodies. The classification accuracy for different land-use classes ranged from 71.23% to 100%. The highest accuracy was observed in water bodies and grass- land, followed by habitation and agriculture, teak forest, degraded mixed forest, and dense mixed forest. The accuracy was lower in open mixed forest, and sal mixed forest. Results revealed that density of different forest types varied from 324 to 733 trees ha-l, basal area from 8.13 to 28.87 ***-1 and number of species from 20 to 40. similarly, the diversity ranged from 1.36 to 2.98, concentration of dominance from 0.06 to 0.49, species richness from 3.88 to 6.86, and beta diversity from 1.29 to 2.21. The sal mixed forest type recorded the highest basal area, diversity was highest in the dense mixed forest, and the teak forest recorded maximum density, which was poor in degraded mixed forests. The study also showed that Normalized Difference Vegetation Index （NDVI） was strongly cor- related to with the shannon Index and species richness.

关键词： forest shannon Index species richness Rs and GIs landuse NDVI

Effects of Milling and Heat Treatment on the synthesis of NiTi Powders

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Journal of Wuhan University of Technology(Materials science) 2017年第5期32卷 1156-1162页

作者： A R sadeghi H Mostajabodaveh A Babakhani M s Abravi A salehi Materials Research Group Iranian Academic Center for EducationCulture and Research(ACECR)Mashhad BranchP.O.Box 91779-49367MashhadIran Faculty of Metallurgical and Materials Engineering Semnan UniversityP.O.Box 35131-19111SemnanIran Department of Materials and Metallurgical Engineering School of EngineeringFerdowsi University of MashhadP.O.Box 91775-1111MashhadIran

This work reports on the production of Ni-50 at% Ti powders by a planetary ball mill in various times（0.5, 1, 2, 6, 20, 36, 54 and 120 h） and subsequent heat treatment in Ar atmosphere at 820 °C. study of powders structure after milling and heat treatment was carried out by scanning electron microscopy and X-ray diffractometry. According to the results, after milling for 6 hours NiTi phase formed, and by the milling evolution up to 54 h, it became the dominant phase. It was found that by the milling development, a layer structure in powder particles was formed, also by increasing the milling time a more homogeneous structure was obtained. Amorphous Ni Ti transformed into ordered Ni Ti, Ni_3Ti, NiTi_2 and minor TiO_2 and TiO after heat treatment at 820 °C for 1 h.

关键词： NiTi milling amorphous heat treatment

Electrochemical process of titanium extraction

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中国有色金属学会会刊：英文版 2007年第2期17卷 429-433页

作者： CH. RVs. NAGEsH C. s. RAMACHANDRAN Defence Metallurgical Research Laboratory HyderabadA.P. India-500058

A wide variety of processes are being pursued by researchers for cost effective extraction of titanium metal. Electrochemical processes are promising due to simplicity and being less capital intensive. some of the promising electrochemical processes of titanium extraction were reviewed and the results of laboratory scale experiments on electrochemical reduction of TiO2 granules were brought out. some of the kinetic parameters of the reduction process were discussed while presenting the quality improvements achieved in the experimentation.

关键词：钛萃取电化学还原过程动力学参数

Electrical characterization of the organic semiconductor Ag/CuPc/Au schottky diode

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Journal of semiconductors 2011年第4期32卷 52-56页

作者： Mutabar shah M.H.sayyad Kh.s.Karimov Ghulam Ishaq Khan Institute of Engineering sciences and Technology physical Technical Institute of Academy of sciences

This paper reports on the fabrication and investigation of a surface-type organic semiconductor copper phthalocyanine（CuPc） based diode.A thin film of CuPc of thickness 100 nm was thermally sublimed onto a glass substrate with preliminary deposited metallic electrodes to form a surface-type Ag/CuPc/Au schottky *** current-voltage characteristics were measured at room temperature under dark *** barrier height was calculated as 1.05 *** values of mobility and conductivity was found to be 1.74×10;cm;/（V·s） and 5.5×10;Ω;·cm;,*** low voltages the device showed ohmic conduction and the space charge limited current conduction mechanisms were dominated at higher voltages.

关键词： schottky diode copper phthalocyanine thin film organic semiconductor mobility

JOINT INVEsTIGATION OF ROTATING FLOW WITH VORTEX BREAKDOWN UsING CFD, VIsUALIZATION AND LDV

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Journal of Hydrodynamics 2005年第4期17卷 455-458页

作者： LIU Ying-zheng CHEN Han-ping KOYAMA Hide s. school of Mechanical and Power Engineering Shanghai Jiaotong University Shanghai 200030 China Department of Mechanical Engineering Tokyo Denki University Tokyo Japan

Vortex breakdown of the steady axisymmetic rotating flow in a confined cylindrical container with a rotating endwall was numerically and experimentally studied. High-quality precision-controlled turntable facilities were established at shanghai Jiaotong University and Tokyo Denki University independently. Collaborative investigations of vortex breakdown were carried out using CFD, Laser Doppler Velocimetry （LDV） and streakline visualization, respectively. The characteristics of vortex breakdown were delineated in terms of comparative investigation using numerical and experimental results. sIMPLEC scheme and FMG multigrid was applied to numerical simulation. Numerical simulation was extensively compared with streakline visualization and LDV measurements, showing qualitative and quantitative agreements.

关键词： vortex breakdown CFD visualization Laser Doppler Velocimetry (LDV)