Yajing YE
,
Litong ZHANG
,
Laifei CHENG
,
Yongdong XU
材料科学技术（英）
Molecular dynamics simulation using a universal force field has been employed to determine the diffusion coefficients of O2 and Na2SO4 vapor into B2O3 and SiC from 700 K to 1273 K, respectively. Einstein diffusion was observed in a 250～300 ps simulation. The diffusion coefficient for the O2 range from about 9.279×10-9 cm2/s for B2O3 to 2.275×10-10 cm2/s for SiC at a loading of 32 molecules per simulation box, that for the Na2SO4 vapor range from about 9.888×10-7 cm2/s for B2O3 to 1.837×10-10 cm2/s for SiC at a loading of 8 molecules per simulation box. Environment properties of C/SiC composite will be increased via the B2O3 preventing the diffusion of O2 and Na2SO4 vapor into the pyrolytic interphase and carbon fibers.
关键词:
Molecular dynamics
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null
,
null
,
null
Haijiang LIU
,
Shaoqing WANG
,
An DU
,
Caibei ZHANG
材料科学技术（英）
The results of molecular dynamics calculations on the interfacial energies and atomic structures of Ag/Ni and Cu/Ni interfaces are presented. Calculation on Ag/Ni interfaces with low-index planes shows that those containing the (111) plane have the lowest energies, which is in agreement with the experiments. Comparing surface energy with interfacial energy, it is found the order of the interfacial energies of Ag/Ni and Cu/Ni containing the planes fall in the same order as solid-vapor surface energies of Ag, Cu and Ni. In this MD simulation, the relaxed atomic structure and dislocation network of (110) Ag||(110) Ni interface are coincident to HREM observations.
关键词:
Molecular dynamics
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null
,
null
,
null
Lianquan GUO
,
Changxiang MA
,
Shuai WANG
,
He MA
,
Xin LI
材料科学技术（英）
The adsorption of hydrogen onto single-walled carbon nanotubes (SWCNTs) was studied by molecular dynamics (MD) simulation. It was found that the hydrogen molecules distribute regularly inside and outside of the tube. Density distribution was computed for H2 molecule. Theoretical analysis of the result showed the multilayer adsorption mechanism of SWCNTs. The storage of H2 in SWCNTs is computed, which provides essential theoretical reference for further study of hydrogen adsorption in SWCNTs.
关键词:
Single-walled carbon nanotubes
,
null
,
null
,
null
Xing ZHAO
,
Shaoqing WANG
,
Caibei ZHANG
材料科学技术（英）
The sintering process of nanometer size gold clusters is investigated by using molecular dynamics simulation in the frame of embedded atomistic method. Several molecular dynamics simulation techniques are used to observe and describe the evolution of the sintering process. The energy distribution for single cluster is examined and the snapshots of sintering process of two clusters are recorded. The evolution of sintering is also described by plotting the mass center changes with time for each cluster. The variations of kinetic and potential energy during the process of sintering are monitored and measured to analyze the dominant mechanisms of sintering from the energy point of view.
关键词:
Sintering
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null
,
null
