【摘要】 目的　研究镧 (Ⅲ ) [La(Ⅲ ) ]、钕 (Ⅲ ) [Nd(Ⅲ ) ]、钐 (Ⅲ ) [Sm(Ⅲ ) ]与L—苏糖酸配合物的稳定性。方法　以pH电位滴定法于I=0 .10mol·dm-3 KNO3 ,维持温度为 2 5± 0 .1℃测定配合物的形成常数。结果　La(Ⅲ )、Nd(Ⅲ )、Sm(Ⅲ )与L—苏糖酸配合物的生成常数分别为 :La(Ⅲ ) 2 .6 2 (110 )、5 .2 3(12 0 )和 -4.93(11- 1) ;Nd(Ⅲ ) 2 .88(110 )、5 .47(12 0 )和 - 3.94(11- 1) ;Sm(Ⅲ ) 3.2 4(110 )、5 .71(12 0 )和 - 3.5 7(11- 1)。结论　La(Ⅲ )、Nd(Ⅲ )、Sm(Ⅲ )苏糖酸配合物的稳定性随离子半径的减小而增大 ,与三离子的离子势的大小顺序一致。更多还原

【Abstract】 Objective To study the stability of complex of L-threonic acid with lanthanum(Ⅲ)[La(Ⅲ)]、neodymium(Ⅲ)[Nd(Ⅲ)] and Samarium(Ⅲ)[Sm(Ⅲ)]. Method The complex formation of L-threonic acid with La(Ⅲ),Nd(Ⅲ) and Sm(Ⅲ) were determined with the way of pH potential titration at I=0.1mol·L -1 ,25±0.1℃. Results The complex formation constant of L-threonic acid with La(Ⅲ),Nd(Ⅲ)and Sm(Ⅲ) were La(Ⅲ)2.62(110),5.23(120)and-4.93(11-1);the formation constant were of Nd(Ⅲ) were2.88(110),5.47(120)and-3.94(11-1);the formation constant were of Sm(Ⅲ) were 3.24(110),5.71(120)and-3.57(11-1).Conclusion The stability of complex of L-threonicacid with La(Ⅲ),Nd(Ⅲ)and Sm(Ⅲ) increased with the increase of Z/r.更多还原