| Resonance Rayleigh Scattering (RRS) and Resonance Nonlinear Scattering (RNLS) such as frequency doubling scattering and second-order scattering has become known for its sensitivity and simplicity as a new analytical technique developed in 1990s. It provides new information concerning molecular structure, size, shape, charge distribution, state of combination and so on. This method has been applied successfully to the study of aggregation of biological macromolecules and the quantitative analysis of biological macromolecules. Moreover, it has been used to the study and determination of trace amounts of inorganic ions and cationic surfactants by means of ion association reactions with some dyes. In addition, this method has been applied to the determination of β-cyclodextrin inclusion constant and the critical micelle concentration (CMC) of surfactants. However, up to now, there is seldom report about the use of this method to study the reaction of lead( Ⅱ) with dyes and its analytical application. Morover there is no report about this technology used to study on the effects of CMC by adding β-CD or dyes in the system of surfactants. Therefore, this thesis has studied the determination of trace amount of lead( Ⅱ) and the effects of β-CD or dyes on the CMC of some surfactants, such as SDS, CTAB and CPB, by using RRS and RNLS.The main contents and some conclusions of the thesis are as follows:1. Resonance Rayleigh scattering study of interaction of Lead( Ⅱ ) and1-(2-pyridylazo)-2-naphthol and its analytical applicationThe RRS spectral characteristics of the interaction of lead( Ⅱ) and PAN and their analytical application have been studied. The results show that in neutral solution in the presence of Triton X-100, lead(Ⅱ) can react with 1-(2-pyridylazo)-2-naphthol (PAN) to form a chelating complex, resulting in a significant enhancement of RRS intensity. The characteristics of RRS spectrum of the chelating complex, the influencing factors and the optimum conditions of the reaction have been investigated. The relationship of the lead( Ⅱ) concentration and the RRS intensity has been studied, with a detection limit for lead(Ⅱ) of 2.5 X 10-5 ug/mL. The method exhibits high sensitivity and has been successfully applied to the determination of trace amounts of lead( Ⅱ) in the tap water.2. Resonance Rayleigh scattering of lead( II )-iodide - methyl violet system and itsanalytical applicationIn dilute phosphoric acid solution, lead(II) reacts with excess of I~ to form [PbI4]2~ anionic complex, which reacts further with methyl violet (MV) to form an ion-association complex. This results in a significant enhancement of RRS intensity and the maximum RRS peak is at 327 nm. The characteristics of RRS spectrum of the ion-association complex, the influencing factors and the optimum conditions of the reaction have been investigated. The intensity of RRS is directly proportional to the concentration of lead(II) from 2.0 X10"3 ug/mL~3.0X 10~2 (ig/mL. The method exhibits high sensitivities and the detection limit is 0.6 ng/mL. The method can be applied to the direct determination of trace amounts of lead in tap water samples.3. Resonance Rayleigh scattering of lead(II)- iodide - rhodamine 6G system and its analytical applicationIn a dilute phosphoric acid medium, lead (II ) can react with excessive I~ to form a complex anion, [PblJ2", which further interacts with Rh6G to form anion-association complex. This can result in a significant enhancement of RRS and the maximum RRS wavelength appears at 315 nm. The characteristics of RRS spectra of the ion-association complex, the influencing factors, and the optimum conditions of the reaction have been investigated. The RRS intensity is directly proportional to the concentration of lead (II) in the range of 4.0 X10~5 ug/mL to 2.0 X1 (T4 ug/mL. The method exhibits high sensitivity, and the detection limit for lead is 3.5 X l(T5ug/mL. The method can be applied to the direct determination of trace amounts of lead ( II) in tap water samples.4. Study on the critical micelle concentration of surfactants in the presence of cyclodextrins by resonance Rayleigh scattering and resonance nonlinear scattering technologyCombined with the electrical conductivity, the technique of RRS and RNLS has been used to study on the effects of CMC by adding P-CD or CM-p-CD in some differents of surfactants, including anion surfactants such as SDS and CPB; cation surfactant such as CTAB. The results show that the CMC of the surfactant is increased by increasing the concentration of p-CD or CM-P-CD, and it can be found that the conclusions agree well with those of electrical conductivity. The methods are very convenient, rapid and accurate and can be used as a new technology for the study of the influence factors on CMC values of surfactants. The application of RRS and RNLS technology has been developed.5. Study on the critical micelle concentration of surfactants in the presence of dyes by resonance Rayleigh scattering and resonance nonlinear scattering technologyThe technique of RRS and RNLS combined with the electrical conductivity, UV-VIS absorption spectrophotometry and fluorescence spectrophotometry has been used to study three kinds of surfactant-dye systems about the the effects of dyes on the CMC of surfactants, including the anion surfactant SDS-methylene blue system,...
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