الفهرس 
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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