用超离心法研究铌胶体的形成。铌浓度大于7×10~(-8)mol/l后开始明显地形成胶体,大于1×10~(-5)mol/l时,形成胶体量剧增。铌形成胶体的趋势与硝酸浓度有关,在约3mol/l处有个(?)折点,低于3mol/lHNO_3,容易形成胶体,而且是多分散的;高于3mol/l HNO_3,形成胶体的倾向变弱,并趋于单分散。 Study on the Formation of Niobium Colloid by Ultracentrifugation. Colloids began to form obviously when the niobium concentration was more than 7 × 10 -8 mol / l. When the concentration of niobium was more than 1 × 10 -5 mol / l, the amount of colloidal colloid increased sharply. The tendency of niobium to form colloids is related to the concentration of nitric acid. There is a (?) Breakpoint at about 3 mol / l. Below 3 mol / l of HNO 3, colloids are easily formed and are more polydisperse. Above 3 mol / l HNO 3, colloidal Weak tendency, and tend to be monodisperse.