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Atomic relaxation,stability and electronic properties of Mg2Sn(100)surfaces from ab-initio calculations

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Journal of Magnesium and Alloys 2016年第1期4卷 62-67页

作者： Hui Ren Wen-Cheng Hu De-Jiang Li Xiao-Qin Zeng Xue Yang Xiao-Shu Zeng Xiang-Jie Yang Bolong Huang Yong Liu Key Laboratory of Near Net Forming of Jiangxi Province Nanchang UniversityNanchang 330031China National Engineering Research Center of Light Alloys Net Forming Shanghai Jiao Tong UniversityShanghai 200240China State Key Laboratories of Metal Matrix Composite Shanghai Jiao Tong UniversityShanghai 200240China Department of Physics and Materials Science City University of Hong KongKowloonHong Kong

Mg2Sn(100)surfaces were investigated using ab-initio method based on density functional theory in order to explore the surface *** is found that both the eleven-layers for Mg-termination surfaces and the nine-layers for Sn-termination surfaces are all converged very *** effects of relaxation mainly occurred within the three outermost atomic layers for both Mg and Sn terminations during the surface ***-termination surfaces are more stable than Sn-termination surfaces according to the analysis of surface *** density of states reveals the metallic property of both Mg-termination and Sn-termination *** bonding exists in Mg2Sn(100)surfaces according to the analysis of partial density of states.

关键词： Magnesium alloy ab-initio calculation Surface energy Surface stability Electronic properties

calculation of electron structure by density function theory and electrochemical process of surface (100) of FeS_2

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Journal of Central South University of Technology 2007年第5期14卷 618-622页

作者：黎全覃文庆孙伟邱冠周 School of Resources Processing and Bioengineering Central South University

The electron structure of FeS2 surface （100） was computed by DFT （density function theory） and the process of electron transfer in sulfide flotation was simulated through ab-initio calculation. The results show that the interaction between xanthate and FeS2 is controlled by the energy of valence band. The products and degree of the reaction depend on the density of state of valence band and concentration election structure on the surface of of positive hole in valence band. Interaction between xanthate and pyrite can be changed by modifying the of the surface of pyrite. Xanthate is adsorbed on the surface of intrinsic pyrite. But the amount of xanthate adsorbed the pyrite with sulfur vacancy is more than that on the surface of the intrinsic pyrite due to the higher electron and vacancy density. Xanthate is not adsorbed on the surface of pyrite with Fe vacancy because of its high Fermi energy

关键词： pyrite electrochemiscal process flotation ab-initio calculation

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Journal of Rare Earths 2018年第10期36卷 1106-1111页

作者： Sardar Ahmad M.Shafiq Rashid Ahmad S.Jalali-Asadabadi Iftikhar Ahmad Department of Chemistry University of Malakand Center for Computational Materials Science University of Malakand Department of Physics Abbottabad University of Science and Technology Department of Physics Faculty of SciencesUniversity of Isfahan

In this paper, we explored the structural, elastic and mechanical properties of the strongly correlated electron systems, intermetallic Ln-Au（Ln = Ce, Pr, Nd, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu） in cubic structure,using PF-LAPW method within the density functional theory. Structural properties of these intermetallics were investigated by treating the exchange-correlation potential with the GGA-PBE, GGA-PBEsol and GGA ＋ U. The effectiveness of the U for the structural properties as compared to other methods confirms the strong correlated nature of these compounds and the calculated lattice constants endorse the divalency of Yb. The results demonstrate the stable cubic CsCl structure of these compounds. Bulk modulus, Young＇s modulus, shear modulus, B/G ratio, Cauchy pressure, Poisson＇s ratio, anisotropic ratio,Kleinman parameters and Lame＇s coefficients were studied using the PBEsol to evaluate their importance in various types of engineering applications. The most prominent features of these compounds are their ductility, very high melting points, resistance to corrosion, and anisotropic nature.

关键词： Strongly correlated electron systems Rare-earth monoaurides Mechanical properties ab-initio calculation

First-Principles calculations on Structure,Elastic and Thermodynamic Properties of Al_2X (X=Sc,Y) under Pressure

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Journal of Materials Science & Technology 2012年第2期28卷 155-163页

作者： Yasemin ztekin iftci Kemal olakoglu Engin Deligz lku Bayhan Department of Physics Gazi University Department of Physics Aksaray University Department of Physics Mehmet Akif Ersoy University

To understand deeply the structural, elastic and thermodynamic characteristics of AI2X （X= Sc, Y） compounds in C15 type （space number 227） Cu2Mg structure, we have performed ab-initio density functional theory within the local density approximation （LDA） and the generalized gradient approximation （GGA）. The thermodynamic properties of the considered structures are obtained through the quasi-harmonic Debye model. We have presented the results on the basic physical parameters, such as the lattice constant, bulk modu- lus, pressure derivative of bulk modulus, second-order elastic constants, Zener anisotropy factor, Poissongs ratio, Youngts modulus, and isotropic shear modulus. In order to gain further information, the pressure- and temperature-dependent behaviour of the volume, bulk modulus, thermal expansion coefficient, heat capacity, entropy, Debye temperature and Griineisen parameter were also evaluated over a pressure range of 0-20 GPa for Al2Sc and 0-17 GPa for Al2Y compound and a wide temperature range of 0-2000 K for both compounds. The obtained results were compared with the other reported values.

关键词： Inter metallic compounds ab-initio calculation Elastic properties Thermodynamic properties

Insights into in-situ TiB/dual-phase Ti alloy interface and its high load-bearing capacity

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Journal of Materials Science & Technology 2022年第24期119卷 156-166页

作者： Qi An Lujun Huang Qi Qian Yong Jiang Shuai Wang Rui Zhang Lin Geng Liqin Wang School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China School of Materials Science and Engineering Central South UniversityChangsha 410083China School of Mechatronics Engineering Harbin Institute of TechnologyHarbin 150001China

To better understand the strengthening mechanism of in-situ formed TiB reinforcements in dual-phase Ti6 Al4 V alloy,the interface characters and properties ofα-Ti/β-Ti/TiB system were thoroughly investigated with the combined use of high-resolution transmission electron microscopy(HRTEM),abinitio calculations,and indentation *** ab-initio calculations suggest that the highly coherent(100)_(TiB)/(121)_(β-Ti)phase boundary(PB)has fairly low interface energy of 0.082 J/m^(2)with an exceptionally high adhesion strength of 6.04 J/m^(2),owing to the formation of strong interfacial Ti–B ionic *** semi-coherent(201)_(TiB)/(0001)_(α-Ti)interface shows a relatively higher interface energy of 1.442 J/m^(2)but still with a fairly high adhesion strength of 4.95 J/m^(2).With the obtained interfacial energetics,thermodynamics analyses were further carried out to explore the nucleation mechanism ofα-Ti in TiB reinforced Ti6Al4V *** to the heterogeneous nucleation at TiB/β-Ti interface,the homogeneous nucleation ofα-Ti within theβ-Ti phase can be more energy-preferred,due to its lower nucleation energy barrier and critical *** indentation tests under various loads of different modes confirmed a remarkably enhanced load-bearing capacity of dual-phase Ti6Al4V alloys,under the critical significance of the strong interfacial bonding achieved by reinforcements of in-situ formed TiB.

关键词： Dual-phase Ti6Al4V alloy In-situ TiB Interface ab-initio calculation Indentation test

ab-initio investigation on bulk and single-layer V2O5 as cathode materials for Li, Na, K, and Mg ion battery

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Ab-initio investigation on bulk and single-layer V2O5 as cat...