Abstract��
This paper studies influence in the preparation of ultra-fines from chemical reduction precipitation, such as the reaction temperature, the density of recipitated slurry,the surfactant on aggregation of cupper ultra-fines. It is found that when the reaction temperature is higher, reaction rate of growing crystal nuclei is very fast and the quickly increasing of the crystal nuclei generation results in that quantity density of the crystal nuclei is too large, the great aggregates and cupper foil are made of crystal nuclei in the reactor.When density of precipitated slurry is too high, because of the collision among particles, big spindly aggregates which are made of ultra-fines are born in reactor at the action of surface energy.They are different aggregation behavior, the former is named ��aggregation of nuclei degree��, as the aggregation is caused by growing nuclei, and because the latter happen among growing granules, it is named ��aggregation of particle degree��.Spherical ultra-fines are produced in the suitable reaction condition.Surfactant is effective on preventing from aggregation of ultra-fines.
2005, Vol. 22 
