PHASE DIAGRAMS OF THE BINARY SYSTEMS TbCl_3-MCl_n(M=Li,Mg,Ca,Pb;n=1 or 2)

The phase diagrams of the binary systems RECl3-MCln（M=Li,Mg,Ca,Pb;n=1 or 2）were investigated bymeans of DTA and X-ray diffraction analysis.It was found that they are of simple eutectic type with eutectic points50.1 Mol.-% TBCl3（445℃）,67.5Mol.-% TbCl3（589℃）,65.9Mol.-% TbCl563℃and 35.6 Mol.-%TbCl3（445℃）respectively.Unstable compounds,formed in the solid slate,are MgTbCl7,CaTb2Cl8,LiTb2Cl7 andPbTbCl5.Their decomposition temperatures are 388℃ with a phase transition at 352,500 and 521℃ with a phasetransition at 483 and 405℃ respectively.Some rules of the phase diagrams were explored.

TbCl_(3)对水中Fe^(3+)的检测

对TbCl_(3)溶液进行荧光测试,发现当Fe^(3+)存在时,Tb^(3+)会有一定的荧光猝灭,在一定范围内,Fe^(3+)的浓度与Tb^(3+)发光强度成线性关系,Tb^(3+)的发光会随着Fe^(3+)浓度的增加而减弱,由此建立了一种新的检测Fe^(3+)的方法。计算出用此方法检测Fe^(3+)的检测限为2.84×10^(-4)mol/L,且对Fe^(3+)的检测具有良好的特异性和选择性。