Papers by Author: Song Ji

Abstract: By means of mechanical properties test and structure observation， the relationship among electric field strength, polar molecule type, content on the Ni/TiO₂ group electrorheological fluid properties have been analyzed. It is found that with increasing electric field strength，the properties of electrorheological fluid increased for same composition ER fluid. Different type polar molecules have distinct effect. For same particle，with increasing polar molecule content，the property is increased, but there is a critical value . Polar molecule make particles chain of electrorheological fluid become strong，coarse and interweaved each other.

Abstract: By means of structure analysis, mechanical properties test and microstructure observation，structure of Ni and Ni/TiO₂ group particles have been obtained, the relationship among partic_{Subscript textSubscript text}le diameter，electric field strength and shear ratio of the properties of Ni/TiO₂ group core-shell particles ER fluid have been researched. It has been found that with increasing particle diameter，the shear stress of ER fluid decreased, and with increasing shear ratio，the shear stress of ER fluid increased for same diameter particle and composition ER fluid. At same time, the smaller of particle diameter, the higher of ER properties such as shear stress, but there is a critical value for shear ratio, when shear ratio is larger than critical value, the properties of ER is nearly a value for same composition ER fluid. Particles chain of ER fluid under certain electric field is different with diversity Ni group Particles.

Abstract: By means of mechanical properties test，the relationship among shear ratio, concentration and electric field, magnetic field ,electromagnetic field on the Ni/TiO2 group electrorheological fluid properties have been analyzed. It is found that with increasing shear ratio，the property of electrorheological fluid increased for same composition ER, but there is a critical value. With increasing concentration，the property of electrorheological fluid increased for same shear ratio. Coupling electromagnetic field makes the properties improve.

Abstract: The preparation and characterization of silver powders with spheric shape and different sizes by chemical reduction of silver ions in the presence of ethanol amine using hydrochinone (C6H6O2) as the reducing agent are described. The size distribution, microstructure, and the phase composition of the obtained Ag Powders were characterized by the Laser Particle Size Analyzer, Scanning Electron Microscope (SEM), Transmission Electron Microscope (TEM) and the X-ray diffraction (XRD). The Ag powder was in face-centered cubic crystal structure with spheric morphology. The average tap density of silver powders is up to 4.0g/cm3. It was also found that the size of the Ag particles can be adjusted conveniently to a certain degree by varying the silver ions content, the addition amount of dispersing agent, the aging time, the temperature of the reaction, and the concentration ratio of hydrochinone to Ag+.