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Effects of annealing treatment on microstructure and tensile behavior of the Mg-Zn-y-nd alloy

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Journal of Magnesium and Alloys 2020年第3期8卷 601-613页

作者： L.y.Sheng b.n.Du Z.y.Hu y.X.Qiao Z.P.Xiao b.J.Wang D.K.Xu y.F.Zheng T.F.Xi Shenzhen Institute Peking UniversityShenzhen 518057China Jiangsu University of Science and Technology Zhenjiang 212003China Institute of Metal Research Chinese Academy of SciencesShenyang 110016China dShenzhen yezhan Electronics Co. LtdShenzhen 518110China

In the present study,the Mg-4Zn-0.6y-0.5nd alloy was hot extruded and annealed at 200℃,225℃ and 250℃ for different time to optimize microstructure and mechanical *** results exhibit that the dual-size grain structure and linearly distributed secondary phase are the main feature of the as-extruded Mg-Zn-y-nd alloy,which can be described as the elongated grain is surrounded by the fine equiaxed ***,the as-extruded alloy shows strong{011^(-)0}fiber texture feature,especially for the large elongated *** annealing treatment results in static recrystallization,which increases fine equiaxed grains but decreases large elongated *** addition,the equiaxed grains formed during the annealing treatment demonstrate relative random orientations,which weaken the{011^(-)0}fiber texture of the ***,during the annealing at 225℃and 250℃,the extension twins begin to form in the alloy and weaken the{011^(-)0}fiber texture of the alloy *** annealing treatment has little influence on the linearly distributed secondary phase but promotes the coarsening of small precipitates at 250℃.The annealing treatment could increase the yield and ultimate strength,but the elongation decreases,especially at higher *** a variation can be ascribed to the evolution of texture,grain structure,twinning and precipitation during the annealing treatment.

关键词： Annealing treatment Mg-Zn-y-nd alloy Microstructure Tensile property

Characterization of planar photonic crystals using surface coupling techniques at large wavelengths

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Chinese Optics Letters 2007年第9期5卷 501-503页

作者： y.b.nachour n.Paraire C.n.R.S. UniversitéParis-Sud 11Institut d'Electronique FondamentaleBt.220-91405Orsay CedexFrance

We report a non-destructive characterization of planar two-dimensional （2D） photonic crystals （PhCs） made in silicon on insulator （SOI） wafers using ellipsometric or Fourier transformed infrared （FTIR） spectroscope. At large wavelengths, devices behave as homogeneous isotropic materials defined by an effective filling factor. The experimental results related to the PhC limited dimensions confirm this characterization.

关键词： Characterization of planar photonic crystals using surface coupling techniques at large wavelengths

Approximate solutions of Klein-Gordon equation with improved Manning-Rosen potential in D-dimensions using SUSyQM

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Chinese Physics b 2014年第12期23卷 38-43页

作者： A.n.Ikot H.Hassanabadi H.P.Obong y.E.Chad Umoren C.n.Isonguyo b.H.yazarloo Department of Physics University of Port HarcourtChoba P M B5323 Port Harcourt Nigeria Department of basic Sciences Shahrood Branch Islamic Azad UniversityShahrood Iran Theoretical Physics Group Department of Physics University of Uyo-NigeriaNigeria

In this paper, we present solutions of the Klein–Gordon equation for the improved Manning–Rosen potential for arbitrary l state in d-dimensions using the supersymmetric shape invariance method. We obtained the energy levels and the corresponding wave functions expressed in terms of Jacobi polynomial in a closed form for arbitrary l state. We also calculate the oscillator strength for the potential.

关键词： Klein–Gordon equation improved Manning–Rosen potential supersymmetric quantum mechanics(SUSyQM)

Superb Strengthening Effect of net-Like Distributed Amorphous Al_(2)O_(3)on Creep Resistance of(b_(4)C+Al_(2)O_(3))/Al neutron-Absorbing Materials

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Acta Metallurgica Sinica(English Letters) 2022年第12期35卷 2007-2013页

作者： y.n.Zan X.Lei J.F.Zhang D.Wang Q.Z.Wang b.L.Xiao Z.y.Ma Key Laboratory of nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Shi-Changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China nuclear Equipment Division Beijing Institute of Nuclear EngineeringChina Nuclear Power Engineering Co.LtdBejing 100840China

b4C reinforced Al composites are widely used as neutron absorbing materials(nAMs)due to excellent neutron absorbing efficiency,however,such nAMs exhibit poor high-temperature *** meet the requirement for structure-function integration,nAMs with enhanced high-temperature mechanical properties are *** this work,a novel(b4 C+Al_(2)O_(3))/Al nAM with netlike distribution of Al_(2)O_(3)was fabricated by powder metallurgy method and subjected to high-temperature tensile creep *** was shown that the creep resistance was enhanced by several orders of magnitude via the addition of only2.1 vol.%netlike-distributed Al_(2)O_(3).(b_(4)C+Al_(2)O_(3))/Al exhibited high apparent stress exponents ranging from 16 to 25 and high apparent activation energy of 364 kJ/*** creep behaviour could be rationalized using the substructure-invariant model and its rupture behaviour could be described by the Dobes-Milicka equation.

关键词： neutron absorber material Al matrix composite Tensile creep b_(4)C/Al

Synthesis,Crystal Structure and Conformational Analysis of (E)-5-Methoxy-2-((4-methoxyphenylimino)methyl)phenol

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Chinese Journal of Structural Chemistry 2010年第3期29卷 359-364页

作者： ■AHn Onura byKGnGR Orhana ALbAyRAK i■demb ODAbA■O■LU Mustafac Department of Physics Faculty of Arts and SciencesOndokuz Mayis University Department of Science Education Sinop University Chemistry Programme Pamukkale University

The title compound,（E）-5-methoxy-2-（（4-methoxyphenylimino）methyl）phenol（C15H15nO3）,crystallizes in monoclinic,space group P21/c with a=9.4361（6）,b=10.6212（5）,c=12.9338（9）,β=93.064（5）o,V=1294.41（14）3,Z=4,Dc=1.320 g/cm3,F（000）=544,Rint=0.116,T=296 K,μ=0.09 mm-1,the final R=0.051 and wR=0.148 for 1836 observed reflections with I2σ（I）.An extensive two-dimensional network of C–H…O hydrogen bonds and π-ring interactions are responsible for the crystal *** hydrogen bonds and C–H…π interactions produce R22（14）,R44（30） and R44（31） *** addition to the molecular geometry from X-ray experiment,the molecular geometry of the title compound in the ground state has been calculated using the semi-empirical（AM1 and PM3） and density functional theory method（DFT）（b3LyP） with 6-31G（d） basis *** determine the conformational flexibility,molecular energy profile of the title compound was obtained by semi-empirical（PM3 and AM1） and DFT/b3LyP calculations with respect to the selected degree of torsional freedom,which varied from –180° to ＋180° in a step of 10°.

关键词： crystal structure Schiff base PM3 AM1 DFT conformational analysis

Some Properties of Si,Ge,and α-Sn Using Pseudopotential Theory

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Communications in Theoretical Physics 2010年第9期54卷 573-577页

作者： P.S.Vyas b.y.Thakore P.n.Gajjar A.R.Jani Department of Physics Sardar Patel University Department of Physics University School of SciencesGujarat University

The pseudopotential theory beyond second order with our well established single parametric model potential is employed to compute total crystal energy, static bulk modulus, energy.b.nd gap at the point X on the Jones-zone face and pressure-volume relation （equation of state under pressure） of Si, Ge and α-Sn using nagy＇s static local field correction function. The results are compared with those obtained using few other local field correction functions. The present results of total energy are in good agreement with the experimental data. bulk modulus calculated by nagy＇s screening function is perfectly matching with the experimental results for Ge and α-Sn. Some deviation is found in the value of energy.b.nd gap.

关键词： pseudopotential total energy semiconductor bulk modulus

A new Method for Characterizing Single Parametric Model Potential

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Communications in Theoretical Physics 2008年第9期50卷 763-766页

作者： P.S.Vyas P.n.Gajjar b.y.Thakore A.R.Jani Department of Physics Sardar Patel UniversityVallabh Vidyanagar 388 120GujaratIndia Department of Physics University School of SciencesGujarat UniversityAhmedabad 380 009GujaratIndia

A novel approach of characterizing single parametric model potential is proposed by equating total pair wise force to zero. Our well-established single parametric model potential is characterized using the proposed idea and compared the obtained parameter with parameters computed by previously used approaches. Thus characterized pseudopotential is then tested to compute total energy of alkali metals. The results establish the reliability of proposed idea of making total pair wise force to zero in determining the parameter of the pseudopotential.

关键词： pseudopotential alkali metals interatomic force bulk modulus

Quality vs. quantity of publications in nanotechnology field from the People’s Republic of China

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Chinese Science bulletin 2008年第8期53卷 1272-1280页

作者： Ronald n. KOSTOFF Ryan b. bARTH Clifford G. y. LAU Office of naval Research 875 N. Randolph St. Arlington 22217 VA USA DDL-OMnI Engineering LLC 8260 Greensboro Drive Suite 600 McLean VA USA Institute for Defense Analyses 4850 Mark Center Drive Alexandria VA USA

This study evaluates trends in quality of nanotechnology and nanoscience papers produced by au- thors from the People’s Republic of China (PRC). The metric used to gauge quality is ratio of highly cited nanotechnology papers to total nanotechnology papers produced in sequential time frames. The USA is both the most prolific nanotechnology publishing country and most represented country on highly cited nanotechnology papers (both in absolute numbers of highly cited papers and highly cited papers relative to total publications) over the 1998―2003 time frame, based on the SCI/SSCI databases. Some of the smaller hi-tech countries have relatively high ratios (~2) of highly cited papers to total publications (e.g. Denmark, netherlands, Switzerland). Countries that have exhibited rapid growth in SCI/SSCI nanotechnology paper production in recent years (e.g. PRC, South Korea) had ratios an order of magnitude less than that of the USA for 1998, but by 2003 had increased to about 20% that of the USA (~2.5). PRC and South Korea have climbed in the publications rankings from 6th and 9th in 1998, re- spectively, to 2nd and 6th in 2005, respectively. PRC’s ratio monotonically increased from 0.16 to 0.45 over the 1998―2003 period, and South Korea’s ratio increased from 0.11 to about 0.6 over that same period, indicating their papers are getting more and more citations proportionately. Thus, under rapid growth conditions, PRC and South Korea have been able to increase their share of participation in highly cited papers. As of 2003, PRC and South Korea have ratios comparable to nations like Japan, France, Italy, and Australia but not yet approaching those of the highly cited countries. none of the top ten publications producing institutions are from the USA, while all of the top ten highly cited publica- tions producers are from the USA. Over the 1998―2003 time period, the top six total publications pro- ducing institutions (globally) remained the same, with Chinese Academy of Scien

关键词：纳米技术纳米科学引用分析中国

Magnetically propelled Carreau fluid flow over penetrable sensor surface influenced by thermal radiation,Joule heating and heat generation

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Communications in Theoretical Physics 2022年第2期74卷 9-18页

作者： b J Gireesha b nagaraja n Srikantha n G Rudraswamy A Felicita Department of Studies and Research in Mathematics Kuvempu UniversityShankaraghattaShivamoggaKarnatakaIndia Department of Mathematics MS Ramaiah Institute of TechnologyBangaloreIndia Department of Mathematics P.C.Jabin Science College(Autonomous)HubballiIndia

This examination emphasizes the analysis of thermal transmission of Carreau fluid flow on a permeable sensor surface equipped with radiation,Joule heating,an internal heat source,and a magnetic *** the above effects and assumptions,the equations that administer the flow are formulated.A configured system of equations is productively reduced to a system of ordinary differential *** reduced system is then dealt with using the Runge–Kutta-Fehlberg fourth–fifth order tool equipped by the shooting *** numerical solutions are utilized to plot graphs and *** conclusion of the study outlines some important findings such as the power law index,the thermal radiation parameter and the heat source parameter enhance the thermal panel whereas the Weissenberg number deescalates the *** power law index and permeable velocity decrease the velocity panel *** representation of streamlines of the flow has been given to strengthen the study.A detailed description has been produced about the results obtained in the study.

关键词： sensor surface Carreau fluid squeezed flow thermal radiation heat generation