| 1 | THE MECHANISM FOR NANOMETER-SIZED TiC SYNTHESIZING BY MECHANICAL & THERMAL ACTIVATION PROCESSING显示文摘A novel process for synthesizing nano-ceramics powders, named mechanical & therm al activation processing, is discussed in the present paper. It is a processing based on thermal activation in liquid phase (molten salt) after mechanical activ ation. The nanometer-sized TiC particles (15-20nm) have been synthesized by the method, and analyzed by X-ray diffraction (XRD), transmission electron microscop e (TEM), scanning electron microscopy (SEM) and energy dispersion X-ray (EDX) sp ectroscopy. An interface interaction between liquid (molten salt) and solid (fin al product particles) phases plays a dominating role for the control of product particles size. The mechanism for the formation of nanometer-sized TiC particles has been discussed. | X.L.Cui L.S.Cui T.Sun M.Zhu | 2005 | Acta Metallurgica Sinica(English Letters)2005，18，3： | 1 |
| 2 | Investigation into rail corrugation in high-speed railway tracks from the viewpoint of the frictional self-excited vibration of a wheel–rail system显示文摘A finite element vibration model of a multiple wheel–rail system which consists of four wheels, one rail,and a series of sleepers is established to address the problem of rail corrugation in high-speed tracks. In the model, the creep forces between the wheels and rail are considered to be saturated and equal to the normal contact forces times the friction coefficient. The oscillation of the rail is coupled with that of wheels in the action of the saturated creep forces. When the coupling is strong, selfexcited oscillation of the wheel–rail system occurs. The self-excited vibration propensity of the model is analyzed using the complex eigenvalue method. Results show that there are strong propensities of unstable self-excited vibrations whose frequencies are less than 1,200 Hz under some conditions. Preventing wheels from slipping on rails is an effective method for suppressing rail corrugation in high-speed tracks. | G.X.Chen X.L.Cui W.J.Qian | 2016 | Journal of Modern Transportation2016，24，2： | 1 |
您所在的机构暂未开通此部分的功能，请联系管理员