Papers by Keyword: Nano-Film

Abstract: In this paper, an effective, simple and universal method for cell immobilization was developed. A self-polymerization nanofilm of poly (dopamine) was used to fix yeast cells in microfluidic channels. The surface morphology of the poly (dopamine) film was characterized by scanning electron microscopy (SEM) and atomic force microscopy (AFM) techniques. Water contact angles (WCA) was also used to characterize the surface property of the poly (dopamine) nanofilm. The WCA on the PDMS substrates rapidly decreased from 105° to 59.8° with an increase in poly (dopamine) coating time. The interfacial process of dopamine self-polymerization and the cell immobilization were measured in a label-free and real-time mode by a surface plasmon resonance (SPR) instrument. Finally the immobilized yeast cells were observed by using a light microscope. From the experimental results, the yeast cells can be easily immobilized on the microfluidic channels modified with the nanofilm of poly (dopamine), which will hold great potential for the immobilization, detection and further analysis of other suspension cells, such as blood cells.

Abstract: A physical model of magnetron sputtering process was built, the distribution of film thickness on the substrate was deduced, and the data were analysised by using the Mathematica and Matlab. The results show that the distribution of the film thickness on the substrate is uneven and it is also influenced by the radius as well as the distance between the target and substrate. The results of experiment correspond fairly well with the theory. The relational expression provides a theoretical basis for evaluation and estimation of the film thickness.

Abstract: The growth of nano CVD diamond films on low index faces such as (111) face and (100) face under different proposed surface chemical reaction model was simulated by using Kinetic Monte Carlo (KMC) method from atomic scale. The results, for example the influence of deposition time t, substrate temperature T_s, and atomic hydrogen concentration [H] on the film deposition rate, surface roughness, and H embedded in the film under different processing conditions, were systematically analyzed and compared. And the adsorption of various species on {111}-oriented diamond cluster was preliminarily computed from electronic scale by Local Density Approximation (LDA) method to assist understanding the surface adsorption mechanism. It is indicated that the film morphology and quality obtained from atomic scale KMC simulation varies according to the chemical reaction models. And our initial electronic scale computation on {111}-oriented diamond cluster showed that single-carbon species can be adsorbed on the activated site more easily than double-carbon species and the former will result in a more stable state than the latter. In order to reveal the nano CVD diamond film growth mechanism, more work about various species adsorption on many different morphological CVD diamond surfaces is needed.

Abstract: Thermal conductivity of L-J potential solid argon nano-films is calculated by equilibrium molecular dynamics (EMD) and nonequilibrium molecular dynamics (NEMD) simulations in the temperature range from 30K to 80K. A LAMMPS computer program has been modified based on classical molecular dynamics. It can be directly used to calculate the thermal conductivity of nano-films in the direction perpendicular to the film plane. Thermal conductivity calculated from this program is compared with experimental data. It is found that this computer program is competent to calculate the thermal conductivity of solid nano-films. It is also found that thermal conductivity is dependent on the simulation temperature and film thickness.