The effect of an external charge on water transportation through T-shaped carbon nanotubes is tested by molecular dynamics simulations.The simulation results show that a relatively small charge reduces the water flux ...The effect of an external charge on water transportation through T-shaped carbon nanotubes is tested by molecular dynamics simulations.The simulation results show that a relatively small charge reduces the water flux through the canbon nanotubes,but a large enough charge prompts the water transportation.This finding may be helpful to biological amplifiers and nanodevices researches.展开更多
In humid environment,a particles can be picked up from the substrate by the capillary force,such as in the colloidal probe of atomic force microscopy technique.In this paper,a model of the capillary bridge between sph...In humid environment,a particles can be picked up from the substrate by the capillary force,such as in the colloidal probe of atomic force microscopy technique.In this paper,a model of the capillary bridge between spherical particles is used to study effect of the friction force in nanoparticles manipulation.Based on the Young-Laplace equation,Newtonian equation and adopted the constant volume boundary condition to calculate the particle motion,the friction force effects on nanoparticles manipulation are analyzed.The results show that the friction force has little effect on the particle motion,and the particle velocity decreases slightly in presence of the friction force.The friction force is opposed to the motion of the nanoparticle.As the tip velocity increases,there is a critical velocity beyond that the particle cannot be picked up from the substrate,and the critical velocity decreases in presence of the friction force.These provide a better understanding of the nanoparticle mechanical properties in humid environment.展开更多
Using molecular dynamics simulations, we show that free diffusion of a nanoscale particle (molecule) with asymmetric structure critically depends on the orientation in a finite timescale of picoseconds to nanoseconds....Using molecular dynamics simulations, we show that free diffusion of a nanoscale particle (molecule) with asymmetric structure critically depends on the orientation in a finite timescale of picoseconds to nanoseconds. In a timescale of ~100 ps, there are ~10% more possibilities for the particle moving along the initial orientation than moving opposite to the orientation; and the diffusion distances of the particle reach ~1 nm. We find that the key to this observation is the orientation-dependence of the damping force to the moving of the nanoscale particle and a finite time is required to regulate the particle orientation. This finding extends the work of Einstein to nano-world beyond random Brownian motion, thus will have a critical role in the understanding of the nanoscale world.展开更多
基金supported by the National Science Foundation of China under grant No.10825520Shanghai Supercomputer Center of China
文摘The effect of an external charge on water transportation through T-shaped carbon nanotubes is tested by molecular dynamics simulations.The simulation results show that a relatively small charge reduces the water flux through the canbon nanotubes,but a large enough charge prompts the water transportation.This finding may be helpful to biological amplifiers and nanodevices researches.
文摘In humid environment,a particles can be picked up from the substrate by the capillary force,such as in the colloidal probe of atomic force microscopy technique.In this paper,a model of the capillary bridge between spherical particles is used to study effect of the friction force in nanoparticles manipulation.Based on the Young-Laplace equation,Newtonian equation and adopted the constant volume boundary condition to calculate the particle motion,the friction force effects on nanoparticles manipulation are analyzed.The results show that the friction force has little effect on the particle motion,and the particle velocity decreases slightly in presence of the friction force.The friction force is opposed to the motion of the nanoparticle.As the tip velocity increases,there is a critical velocity beyond that the particle cannot be picked up from the substrate,and the critical velocity decreases in presence of the friction force.These provide a better understanding of the nanoparticle mechanical properties in humid environment.
基金supported by the National Natural Science Foundation of China(Grant Nos. 10825520,11105088,11175230 and 11290164)Shanghai Supercomputer Center and Supercomputing Center of Chinese Academy of Sciences
文摘Using molecular dynamics simulations, we show that free diffusion of a nanoscale particle (molecule) with asymmetric structure critically depends on the orientation in a finite timescale of picoseconds to nanoseconds. In a timescale of ~100 ps, there are ~10% more possibilities for the particle moving along the initial orientation than moving opposite to the orientation; and the diffusion distances of the particle reach ~1 nm. We find that the key to this observation is the orientation-dependence of the damping force to the moving of the nanoscale particle and a finite time is required to regulate the particle orientation. This finding extends the work of Einstein to nano-world beyond random Brownian motion, thus will have a critical role in the understanding of the nanoscale world.