DBC—偶氮氯膦光度法测定地质样品中15种稀土元素的研究

Determination of Fifteen Rare Earth Elements in Geological Samples by Spectrophotometry with DBC-Chlorophosphnozo-Rare Earth Elements System

建立了DBC—偶氮氯膦—稀土元素显色体系 ,该体系的灵敏度高 ,摩尔吸光系数为 (1.3× 10 4 ～1.2× 10 5)L·mol- 1·cm- 1,体系稳定 ,重现性好 ,并将偏最小二乘计算法用于数据处理中 ,较准确地预测出地质样品中 15种稀土元素各自的含量 ,其标准偏差 (S)为 3.3× 10 - 4～ 9.1× 10 - 3,相对标准偏差为0 .81%～ 5.0 % ;其相对误差一般都小于 15% 。

This article established DBC-chlorphosphnozo-REE colour system.This system have high sensitivity. The molar absorptivity is (1.3×10 4～1.2×10 5) L·mol -1 ·cm -1 . This system have good stationbility and have good reproducibility . The least square method is used in data processing and accurately predicted the quantity of fifteen rare earth elements in geological sample. The results are satisfactory. Key words: rare earth elements; DBC-chlorophosphnozo; partial least square spectrophotometryi ② (① Dept. of Arch., Huaqiao Univ., 362011, Quanzhou; ② Gulangyu Scenic Spot Constr. & Devel. Co., 361000, Xiamen) Abstract From the angle of force balance,a physical and mathematical model of liquid outside the insert plate when the angle of solid liquid contact equals to zero is established; and the surface curve shape of liquid is derived and proved. And then, the general conditions during which the angle of solid liquid unequal to zero degree are derived and proved. By way of discussion, three meaningful conclusions are obtained: (1) For a certain liquid, the actual height of the rise of the liquid differs with the insert plates of different materials, however, all the highest points of solid liquid contact fall on the same curve. (2) The accuracy of the surface tension can be promoted by measuring line distance instead of angle of contact.(3) The relative errors for surface tension calculated by line distance are twofold of the relative errors for measuring line distance.