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Abstract This thesis is comprised of three chapters as follows: The first Chapter is concerned with some of marine pollutants. Firstly, polycyclic aromatic hydrocarbons PAHs, secondly phenols and thirdly, heavy metals with focus on their sources and toxicities. This chapter also includes a general recent survey on analytical methods used for assessment and detection of these three categories of marine pollutants. The second chapter illustrates the experimental work, the chemicals used, the instruments, methods of preparation for solutions and working procedures more over calculations which are used in the study. The third chapter includes the results and discussion of the obtained work in the thesis, this chapter is divided into three parts: Part (III.A.) Detection of PAHs, phenols and heavy metal ions by using Eu(III), Tb(III)-coumarin-3-carboxylic acid (CCA) complexes The UV absorption spectra for Eu(III)-CCA and Tb(III)- CCA binary complexes in comparison with the free ligand CCA are carried out in different solvents: water, methanol and ethanol for free ligand while water, methanol, ethanol, isopropyl alcohol and ethyl acetate for both complexes. The fluorescence spectra for the complexes are also studied in the same solvents in addition diethyl ether, DMSO, hexane, 1,4-dioxane, acetonitrile for Eu(III)-CCA complex and Tb(III)-CCA except diethyl ether for Tbcomplex. The obtained data reveals that for Eu(III)-CCA complex, it is Summary Page 403 centrosymmetric in aqueous medium and in isopropyl alcohol, while the complex is not centrosymmetric in methanol, ethanol, ethyl acetate, diethyl ether, DMSO, hexane, 1,4-dioxane and acetonitrile. Such observation is obtained through the ratio I616/ I593 for Eu(III) complex in each solvent. The hypersensitive emission peak for Eu(III) at = 616 nm follows the order: DMSO> methanol > diethyl ether > ethanol > hexane > ethyl acetate > 1,4-dioxane > acetonitrile > isopropyl alcohol > water. The hypersensitive emission peak for Tb(III) at = 544 nm follows the order: methanol > isopropyl alcohol > DMSO > water > acetonitrile > 1,4-dioxane > hexane > ethyl acetate > ethanol. These results indicate that the maximum emissions for Eu(III)-CCA and Tb(III)-CCA complexes were observed in methanol. Moreover the best stoichiometry for both complexes was 1:2. Interaction with PAHs The interactions of different concentrations of four PAHs (acenaphthene, anthracene, naphthalene, fluorene) with Eu(III)-(CCA)2 complex were accompanied by decrease of the characteristic emission peak intensity for Eu(III) at = 615/616 nm, i.e. PAH acted as a quencher, where the Stern-Volmer quenching constants (KSV) were (1.14, 4.69, 7.37, 21.8 ) x104 mol-1 L for acenaphthene, anthracene, naphthalene and fluorene respectively. While the limits of detection (LOD) varied from the lowest 0.45 μmol L-1 for fluorene then 1.34 μmol L-1 for naphthalene and 1.81 μmol L-1 for acenaphthene and the highest for anthracene 4.26 μmol L-1 . It was found that the binding constants of studied PAHs with Eu(III)-(CCA)2 probe followed the order: anthracene > naphthalene > fluorene > Summary Page 404 acenaphthene. Moreover, the number of binding sites was 1 site except for anthracene was 2 sites. The quenching mechanism based on the Stern-Volmer quenching constant (KSV) was determined for anthracene, naphthalene and fluorene. It was noted that the dynamic collision model was the quenching mechanism for their interaction with Eu(III)-(CCA)2 probe. The binding modes observed were attributed to the van der Waals force or hydrogen bond formation being the leading contributor to the binding occurred between anthracene and naphthalene with Eu-complex. Otherwise for fluorene the hydrophobic interaction was the leading contributor to the binding. On the other hand, the observed fluorescence response of Tb(III)- (CCA)2 probe to interact with 4 PAHs (acenaphthene, anthracene, naphthalene, fluorene) were carried out in methanol, the probe exhibited a quenching in luminescence intensity for hypersensitive peak for Tb(III) at = 544 nm by1.6-fold with addition of anthracene while acenaphthene, naphthalenean and fluorene caused less responses upon their addition to Tb(III)-(CCA)2 complex. The limit of detection of anthracene was 6.49 μmol L-1, moreover the binding constant was 3.24 x103 mol-1 L and the number of binding sites was one site. The quenching mechanism was dynamic collision moreover the binding mode was van der Waals force or hydrogen bond formation being the leading contributor to the binding occurred between anthracene with Tb(III)-(CCA)2 probe. Summary Page 405 Interaction with phenols The interactions of different concentrations of (2,4-dichlorophenol (2,4- DCP) and phenol ) with Eu(III)-(CCA)2 complex were accompanied by decrease of the characteristic emission peak intensity for Eu(III) at = 616 nm, i.e. phenols acted as a quencher, where the Stern-Volmer quenching constants (KSV) equal (1.13 x107 and 6.2 x104) mol-1 L for 2,4- dichlorophenol and phenol respectively. While the limits of detection (LOD) were 2.65 x10-8 mol L-1 for 2,4-dichlorophenol while 2.24 μmol L-1 for phenol. It was found that the bind |