Nano-Copper and Cu/UDD (ultradispersed diamond) nanocomposites were separately prepared by reduction of CuCl2 aqueous solution and that doped with 0.7%(weight percent) of ultra-dispersed diamond. The as prepared nano-...Nano-Copper and Cu/UDD (ultradispersed diamond) nanocomposites were separately prepared by reduction of CuCl2 aqueous solution and that doped with 0.7%(weight percent) of ultra-dispersed diamond. The as prepared nano-crystals were characterized by X-ray diffraction (XRD), transmission electron microscope (TEM), Fourier transform infrared spectroscopy (FTIR) and electron paramagnetic resonance techniques (EPR). It was found that homogeneous nucleation dominated the aqueous reduction reaction at high concentration and the diameter of nano-copper decreased as the reaction time shortened, yet at lower concentration heterogeneous nucleation predominated and the doped UDD functioned as heterogeneous nucleation. Otherwise large number of free-radicals existed in the nano-composites. Both of nano-copper and Cu/UDD nanocomposites were strong catalysts for AP decomposition, with Cu/UDD being a more effective one. The higher decomposition temperature for AP was 119 ℃ lower than that without catalyst. And the exothermic quantity of decomposition was from 590 J·g-1 to 1 400 J·g-1 by mix 2% of the Cu/UDD nanocomposites.展开更多
Nano-copper used as lubrication oil additive has good tribological property and active self-repairing effect for friction pairs. The reduction in liquid phase for preparing nano-additive is one of the most common meth...Nano-copper used as lubrication oil additive has good tribological property and active self-repairing effect for friction pairs. The reduction in liquid phase for preparing nano-additive is one of the most common method. Nano-copper was prepared by reduction in liquid phase. The different project and routine practice for preparing nano-copper were researched. The dispersion problem of nano-copper was investigated by surface treatment and high dispersion. The particles dimension, the dispersion stability and the purity of nano-copper were characterized by TEM and XRD. The conclusion indicates that the methods of the preparation and dispersion can obtain 20nm copper additive with good dispersion property in lubrication oil.展开更多
文摘Nano-Copper and Cu/UDD (ultradispersed diamond) nanocomposites were separately prepared by reduction of CuCl2 aqueous solution and that doped with 0.7%(weight percent) of ultra-dispersed diamond. The as prepared nano-crystals were characterized by X-ray diffraction (XRD), transmission electron microscope (TEM), Fourier transform infrared spectroscopy (FTIR) and electron paramagnetic resonance techniques (EPR). It was found that homogeneous nucleation dominated the aqueous reduction reaction at high concentration and the diameter of nano-copper decreased as the reaction time shortened, yet at lower concentration heterogeneous nucleation predominated and the doped UDD functioned as heterogeneous nucleation. Otherwise large number of free-radicals existed in the nano-composites. Both of nano-copper and Cu/UDD nanocomposites were strong catalysts for AP decomposition, with Cu/UDD being a more effective one. The higher decomposition temperature for AP was 119 ℃ lower than that without catalyst. And the exothermic quantity of decomposition was from 590 J·g-1 to 1 400 J·g-1 by mix 2% of the Cu/UDD nanocomposites.
文摘Nano-copper used as lubrication oil additive has good tribological property and active self-repairing effect for friction pairs. The reduction in liquid phase for preparing nano-additive is one of the most common method. Nano-copper was prepared by reduction in liquid phase. The different project and routine practice for preparing nano-copper were researched. The dispersion problem of nano-copper was investigated by surface treatment and high dispersion. The particles dimension, the dispersion stability and the purity of nano-copper were characterized by TEM and XRD. The conclusion indicates that the methods of the preparation and dispersion can obtain 20nm copper additive with good dispersion property in lubrication oil.
