Papers by Author: Liang Fang

Abstract: The growth process and corrosion resistance of the phosphate coating on 25Cr2Ni4WA alloy steel fabricated by a high temperature manganese phosphating were investigated by XRD, SEM, EDS and electrochemical polarization method, respectively. It is found that the phosphate coating consists of lots of close packed lump crystallites and mainly composed of (Mn,Fe)₅H₂(PO₄)₄·4H₂O. The coating weight increased rapidly, and then the increase rate slowed down when phosphating process was carried for about 5 min. The corrosion potentials of the phosphated steel shifted positively about 250 mV than the bare steel, indicating that the phosphating can improve the corrosion resistance of the 25Cr2Ni4WA alloy steel.

Abstract: n-doped ZnO (ZnO:In) thin films with 0~9at.% In content have been prepared by RF high magnetron sputtering on glass substrate. All the films were annealed in N₂ at 473K for 1h. The effect of In doping concentration on the structure, surface morphology, electrical properties,Seebeck and magnetoresistive effect of the films were investigated. It was found that the crystal quality of the films degrades, and the surface gets rough with increasing In content. The lowest resistivity of the ZnO:In thin films 6.1×10^-4Ω.cm occurs at 5at.% in the target doping concentration. All the films show a striking Seebeck effect and the absolute value of the Seebeck coefficient decreases under magnetic field. Meanwhile, a positive magnetoresistance of the films was found. ZnO thin films with 1at.% In-doped is best for the thermoelectric material, which has the largest power factor of 2.1×10^-4W/K²m at room temperature.

Abstract: The density of Ni-Co-Al ternary alloys with a relative fixed mole ratio of Ni/Co(xNi:xCo≈86:14) and aluminum concentration change from 0 to 10% mass fraction in liquid states were measured by a modified pycnometric method(MPM). It was found that the density of the liquid Ni-Co-Al alloy decreases with increasing temperature, Al concentration and the ratio of Al concentration to Ni concentration in the alloy. The temperature coefficient of density changes with increasing the Al concentration or the ratio of Al concentration to Ni concentration in the ternary alloys. The measured densities by MPM were comparable with that by the modified sessile drop method, the maximum difference of density between them was about ±0.56%. The molar volume of liquid Ni-Co-Al alloy increases with increasing temperature and changed with increasing Al concentration. And the partial molar volume of aluminum in Ni-Co-Al alloy was calculated approximately. The molar volume of liquid Ni-Co-Al ternary alloy determined in the present work shows a negative deviation from the ideal linear molar volume.

Abstract: An angular velocity of flow sensor for liquids based on single-walled carbon nanotube thin films is presented. The carbon nanotubes in this study were fabricated on Si substrate by hot filament chemical vapor deposition (CVD). The experimental results showed that the flow-induced current on the surface of carbon nanotube thin films was closely depended upon the angular velocity, concentration, properties and temperature of the liquids. The current increased with increasing angular velocity, concentration and temperature of the liquids. In this study, the liquids such as water, NaCl solution and other electrolyte were flowing over the sensor. The results obtained were also discussed. The theoretical and experimental studies have shown that there was electronic friction and electron drag effect of carbon nanotubes in flowing liquids. This effect in carbon nanotubes can be used for a new flow sensor.