Papers by Author: Xian Ming Zhang

Abstract: Many factors affect the determination of moisture content in oil by Karl Fischer Method; there are objective factors such as water, samples and temperature environment, respectively 46# turbine oil and 25# transformer oil for example, from a gross error, correlation coefficient, and other subjective perspective, the causes of error are analyzed; correlation coefficient very close to 1 and most of the relative error in ( -0.15,0.00) are discussed, which shows that high measuring accuracy and precision of this method.

Abstract: Tribological study on a 12.7 mm diameter steel ball bearing specimen has been carried out in a four-ball machine. The synthesis of 3-(N-n-octadecylammonium) quinazolin-4-ones was described. The 3-(N-n-octadecylammonium) quinazolin-4-ones has been found to be quite effective as a potential ashless additive without phosphorus and sulphur in liquid paraffin according to the experimental results. Employing scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS), the film formed when the the additive interreacted with the metal was investigated.

Abstract: In the development of new large megawatt size wind turbines, aerodynamic and structural reserch is interesting and important for study wind turbine performace and boost the development of wind power. In this paper, the aerodynamic and aeroelastic characteristic of blades is investigated and presented based on Blade Element Momentum and Hamilton theory. Then the flexible characteristics of balde is researched with the aerodynamic and aeroelastic model of the rotor. The flapwise and edgewise displacements, velocities and accelerations of blade tip are simulated and plotted to validate the model which is presented in this paper. The results have very important significance to investigate the vibration and fatigue lifetime of the wind turbine blades.

Abstract: A heterocyclic derivative of 3-(N-di-n-butylaminomethyl) quinazolin-4-ones was synthesized and its tribological behavior as an ashless additve without phosphorus and sulphur in liquid paraffin was evaluated using a four-ball tester. On the basis of the experimental results, the novel additive has been found to be quite effective as a potential additive in liquid paraffin. The nature of the film on the rubbed surface was investigated by scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS).