الفهرس 
Chemistry of lanthanidesOnly 14 pages are availabe for public view
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Abstract
The thesis comprises three chapters : 1) Chapter I comprises an introduction on the chemistry of lanthanides including a literature survey on coordination chemistry of lanthanide ions, formation constants of complex species, potentiometric determination of the formation constants of lanthanide complexes and spectrophotometric determination of lanthanide ions. A literature survey is also given on J-acid, J-acid azo dyes and their applications and chemistry of azo dyes. 2) Chapter I1 includes the materials and reagents used as well as the experimental techques. It comprises details concerning the preparation of some J-acid azo dyes, solutions, instruments used, working procedures and methods of calculations. 3) Chapter I11 includes the results and discussions. a) In solution, the conditions favouring the formation of the complexes of trivalent Sc, Y, La, Ce, Pr, Sm, Eu, Gd, Tb, Dy, Ho and Yb ions with 5- (p-nitropheny1azo)-6-amino-1-hydroxynaphthalene -3- sulphonic acid and trivalent Pr, Sm, Eu, Gd, Tb, Dy, Ho, Yb and hexavalent U02 ions complexes with 5-(p-arsono-phenylazo) -6-amino- 1 -hydroxynaphthalene -3- sulphonic acid were studied. The stoichiometries of the formed complexes were investigated using different methods, e.g. molar ratio and continuous variation methods. The results indicate that all ligands form 1:l 1:2 and 1:3 (M:L) complexes. b) Studies on the influence of pH, time, sequence of addition, foreign ions and spectrophotometric titration with EDTA were given. c) Beer’s law obeyence for the above mentioned metal ions was reported. The Ringbom range was also calculated. d) The ionization constants (pKd of ligands If and I1 were determined spectrophotometrically using the half - hight and limiting absorbance methods. e) The stability constants of the above mentioned metal chelates were calculated using absorbance - pH relation and Harvey-Manning technique. 0 The ionization constants (pK3 of ligands Ib, I,, I,, If, Ih, Ii, Ij, Ik, 11 and I, were determined potentiometrically using Sarin and Munshi titration technique. g) The stability constants of trivalent Sc, Y, La, Ce, Pr, Sm, Eu, Gd, To, Dy, Ho, Yb and haxavalent UO2 ions with Ib-Io were determined potentiometrical~y, log B values were calculated using interpolation at half ii values, correction term, successive approximation and mid-point methods. Correlation between the basicity of the ligands and stability of complexes was also interpretted. h) Conductimetric titrations were carried out to give further insight to the stoichiometric composition of the chelates formed in solutions. i) Infrared spectra of the investigated ligands were scamed as KBr discs and the characteristic bands were assigned to their vibrational modes. The thesis ends with summary and list of references which were of great help in this study.