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chemical potential of Vacancies in Metal Crystals

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材料科学与工程学报 2000年第Z1期20卷 109-111页

作者： SUN Jun State Key Laboratory for Mechanical Behavior of Materials School of Materials Science and Engineering Xi'an Jiaotong University Xi'an 710049 China Materials Technology Laboratory MTL/CANMET Ottawa Canada

In this paper, a concept, the chemical potential of vacancies in metal crystals, has been derived from the partial mole free energy of vacancies based on a model of an atom-vacancy binary *** a pure metal crystal containing the mole concentration of vacancies, Cv and it's value in thermal equilibrium,C0, at temperature T the chemical potential can be expressed respectively as: μ v(Cv)=RT[1+1n(C√Co)]and μ v (Co)=RT The second term in μ v(Cv) is the chemical potential of the vacancies referred to the standardstate concentration given by J. P. Hirth [1] and first term is the standard-state one presented in this paper.

关键词： chemical potential thermal equilibrium temperature T metal crystal free energy

Shear Viscosity of Hot QED at Finite chemical potential from Kubo Formula

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Communications in Theoretical Physics 2008年第8期50卷 429-436页

作者： LIU Hui HOU De-Fu LI Jia-Rong Department of Physics Jinan University Guangzhou 510632 China Institute of Particle Physics Central China Normal University Wuhan 430079 China

Within the framework of finite temperature field theory this paper discusses the shear viscosity of hot QED plasma through Kubo formula at one-loop skeleton diagram level with a finite chemical potential The effective widths (damping rates) are introduced to regulate the pinch singularities and then gives a reliable estimation of the shear viscous *** finite chemical potential contributes positively compared to the pure temperature case. The result agrees with that from the kinetics theory qualitatively.

关键词： shear viscosity QGP finite-temperature field theory chemical potential

Relationship between Oxygen chemical potential and Steel Cleanliness

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Journal of Iron and Steel Research International 2005年第5期12卷 28-33,62页

作者： Mansour Soltanieh Yousef Payandeh Iran University of Science and Technology Narmak Tehran 16844 IranIran University of Science and Technology Narmak Tehran 16844 Iran

To investigate inclusion formation in each step during steel making process, several samples were taken in different steps of the production of steel at Mobarakeh Steel Co of Esfahan to measure the oxygen chemical potential of the molten steel in each stage. The chemical compositions of the inclusions in samples were investigated by scanning electron microscope. The chemical composition of the slag was analyzed. With the use of thermodnamic calculations and chemical analysis of the melt, at the working temperature, the relationship between dissolved oxygen and other elements were determined. Finally, it was found that there is a close relationship between inclusions formed in each step with the oxygen partial pressure.

关键词： inclusion steel cleanliness oxygen chemical potential

Critical Number of Fermion Flavors at Finite chemical potential in QED3

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Communications in Theoretical Physics 2005年第6X期44卷 1055-1060页

作者： FENG Hong-Tao HE Xiang HOU Feng-Yao SUN Wei-Min ZONG Hong-Shi Department of Physics Nanjing University Nanjing 210093 China Joint Center for Particle Nuclear Physics and Cosmology Nanjing 210093 China CCAST (World Laboratory) P.O. Box 8730 Beijing 100080 China

We propose a new method for calculating the dressed fermion propagator at finite chemical potential in QED3 under the rainbow approximation of Dyson-Schwinger equation. In the above approximation, we show that the dressed fermion propagator at finite chemical potential # has the form S（p） = iγ.p^-A（p^-2）＋ B（ p^-2） with p^-μ= （p^-1p3 ＋ iμ）. Using this form of fermion propagator at nonzero chemical potential, we investigate the Dyson-Schwinger equation for the dressed fermion propagator at finite chemical potential and study the effects of the chemical potential on the critical number of the fermion flavors.

关键词： DS equation chemical potential critical number of the fermion flavors

Colour Conductivity of a Quark Plasma at Finite chemical potential

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Chinese Physics Letters 2002年第7期19卷 912-914页

作者：张超郑小平等 DepartmentofPhysics HuazhongNormalUniversityWuhan430079

We apply non-Abelian transport theory to a low-temperature case, and discuss the colour electric dynamics of cold-dense quark matter at large chemical potential. Finally, at leading logarithmic accuracy, the colour co... 详细信息

关键词： chemical potential

Influence of Finite chemical potential on Critical Boson Mass in QED3

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Communications in Theoretical Physics 2007年第3期47卷 525-528页

作者： ZHANG Yun-Qiang LI Zhen FENG Hong-Tao Department of Technology and Physics Zhengzhou University of Light Industry Zhengzhou 450002 China Zhengzhou Teacher＇s College Zhengzhou 450044 China Department of Physics Nanjing University Nanjing 2100931 China

Using the coupled Dyson-Schwinger equation for the fermion propagator at finite chemical potential μ, we investigate the fermion chiral condensate when the gauge boson mass is nonzero in QED3. We show that the chiral... 详细信息

关键词： DSE chemical potential critical boson mass

A stepwise simulation approach to the chemical potential of fluids

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Chinese Journal of Chemistry 1994年第2期12卷 105-112页

作者： WU, Xiong-Wu SHI, JunDepartment of chemical Engineering, Nanjing Institute of chemical Technology, Nanjing, Jiangsu 210009, ChinaWANG, Wen-ChuanDepartment of chemical Engineering, Beijing Institute of chemical Technology, Beijing 100029, China Department of chemical Engineering Nanjing Institute of Chemical Technology Nanjing Jiangsu 210009 China Deportment of chemical Engineering Beijing Institute of Chemical Technology Beijing 1000S9 China

A new approach to the computation of the chemical potential of fluids is presented. In this method the particle-insertion operation in the conventional test particle method is replaced by the growth of a specific particle. Application of the new technique to hard sphere and Lennard-Jones fluids shows that it is capable of providing reliable estimates of the chemical potential, even at high density where the conventional test particle methods are difficult to apply.

关键词： chemical potential molecular simulation computation method hard sphere LennardJones fluids.

Unexpected Kirkendall effect in twinned icosahedral nanocrystals driven by strain gradient

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Nano Research 2020年第10期13卷 2641-2649页

作者： Jingbo Huang Yucong Yan Xiao Li Xurong Qiao Xingqiao Wu Junjie Li Rong Shen Deren Yang Hui Zhang State Key Laboratory of Silicon Materials School of Materials Science&EngineeringCyrus Tang Center for Sensor Materials and ApplicationsZhejiang UniversityHangzhou 310027China Advanced Technology Department SAIC Motor Corporation LimitedShanghai 201804China State Key Laboratory of Heary Oil Proessing School of Materials Science and EngineeringChina University of PetroleumQingdao 266580China

Nanoscale Kirkendall effect has been widely used for rationally fabricating high-quality hollow nanocrystals, but often requires the intrinsic diffusion coefficient of out-diffusion materials higher than that of in-diffusion components. Here we demonstrate an unexpected Kirkendall effect that occurs in diffusing intrinsically faster Cu atoms into Pd icosahedra, leading to the formation of PdCu alloyed hollow nanocrystals. The control experiment with Pd octahedra replacing icosahedra indicates the critical role of twin boundaries in facilitating such unexpected Kirkendall effect. In addition, geometric phase analysis and density functional theory calculation show that out-diffusion of Pd atoms in the icosahedra is faster than in-diffusion of Cu atoms, particularly through the twin boundaries, upon the strain gradient with an inward distribution from tensile to compressive strains. The unexpected Kirkendall effect is also found in the interdiffusion of Ag and Pd atoms in Pd icosahedra. Our finds break the limitation of the intrinsic diffusion coefficient for the synthesis of hollow nanocrystals through Kirkendall effect and are expected to enormously enrich the family of hollow nanocrystals which have shown great potential in broad areas, such as fine chemical production, energy storage and conversion, and environmental protection. This work also provides a deep understanding in the diffusion behavior of atoms upon the strain gradient.

关键词： Kirkendall effect diffusion coefficient interdiffusion chemical potential icosahedral nanocrystals strain gradient

Ion adsorption components in liquid/solid systems

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Journal of Environmental Sciences 2006年第6期18卷 1167-1175页

作者： WU Xiao-fu HU Yue-li ZHAO Fang HUANG Zhong-zi LEI Dian College of Resource and Environment Central South University of Forestry and Technology Changsha 410004 China

Experiments on Zn^2＋ and Cd^2＋ adsorptions on vermiculite in aqueous solutions were conducted to investigate the widely observed adsorbent concentration effect on the traditionally defined adsorption isotherm in the adsorbate range 25--500 mg/L and adsorbent range 10--150 g/L. The results showed that the equilibrium ion adsorption density did not correspond to a unique equilibrium ion concentration in liquid phase. Three adsorbate/adsorbent ratios, the equilibrium adsorption density, the ratio of equilibrium adsorbate concentration in liquid phase to adsorbent concentration, and the ratio of initial adsorbate concentration to adsorbent concentration, were found to be related with unique values in the tested range. Based on the assumption that the equilibrium state of a liquid/solid adsorption system is determined by four mutually related components： adsorbate in liquid phase, adsorbate in solid phase, uncovered adsorption site and covered adsorption site, and that the equilibrium chemical potentials of these components should be equalized, a new model was presented for describing ion adsorption isotherm in liquid/solid systems. The proposed model fit well the experimental data obtained from the examined samples.

关键词： adsorbent effect adsorbate/adsorbent ratio adsorption component chemical potential Zn^2+ Cd^2+ vermiculite