| Resonance Rayleigh scattering(RRS)spectrum is a new,sensitive and simple spectral technique.It can be obtained by the synchronous scanning technique on a fluorescence spectrophotometer.It brings to extensive attention and interesting in recent years and has been applied to determination of some biomacromolecules,trace inorganic,organic substances and pharmaceutical analysis,and also to the field of environmental analysis.However,up to now it is seldom applied to the study of water treatment chemical,Cl2,ClO2 and its by-products.It is very important to establish a simple,rapid,sensitive,selective method for determination of trace Cl2, ClO2 and its by-products.Therefore,in the dissertation,the reaction of ClO2,Cl2 and ClO2- with I--rodamine dyes,sufactants and silver nanoparticles have been studied by resonance scattering spectra,fluorescence spectra,UV-Vis absorption spectra coupling with scanning electron microscope and laser scattering technology.Their spectral optimum reaction conditions, influencing factors and analytical applications have been examined.Furthermore,the reasons of RRS enhancement,the relationship between RRS spectra and absorption spectra are discussed. Some new,simple,convenient,rapid and sensitive RRS methods are proposed for the determination of ClO2,Cl2 and ClO2-.This is new development of the RRS technology used in the analytical application of the inorganics.In addition,the analytical methods of chlorine dioxide,chlorine and chlorite,the theory of resonance Rayleigh scattering and their applications were reviewed.The main contents and some conclusions of the dissertation are as follows:1.A Novel and Selective Resonance Scattering Spectral Method for the Determination of Trace ClO2 Using Rhodamine DyeIn HCl-NaAc buffer solutions,ClO2 oxidize I- to form I2 and then the excess I- reacts with I2 to form I3-.The I3- combine respectively with rhodamine dyes,including rhodamine B(RhB),butyl rhodamine B(b-RhB),rhodamine 6G(RhG)and rhodamine S(RhS)to form association particles which exhibit stronger resonance scattering effect at 420nm.The resonance scattering intensity for the system of RhB,bRhB,RhG and RhS at 420nm is proportional to chlorine dioxide concentrations in the range of 0.0056-0.787μg/mL,0.0034-0.396μg/mL,0.0057-0.795μg/mL and 0.0052- 0.313μg/mL,respectively.The detection limits of the systems were 0.0011μg/mL,0.006μg/mL, 0.0054μg/mL and 0.0023μg/mL ClO2,respectively.A novel resonance scattering spectral(RSS) method for determination of chlorine dioxide has been proposed,based on the formation of association complex particles of RhB-I3.This method has high sensitivity,good selectivity and precision,and has been used for the determination of ClO2 in drinking water with satisfactory results.2.Resonance Rayleigh scattering spectral study of Cl2 -KI- rodamine dyes and its analytical applicationsIn Na2HPO4-citric acid buffer solution,Cl2 can oxidize I- to form I2 and then it reacts with excess I- to form I3-.The I3- combines respectively with rhodamine dyes,including rhodamine B (RhB),butyl rhodamine B(b-RhB),rhodamine 6G(RhG)and rhodamine S(RhS),to form association particles which give stronger resonance scattering(RS)effect at 400 nm.The RS intensity of the RhB,b-RhB,RhG and RhS systems is proportional to chlorine concentrations in the range of 0.008-1.74,0.019-1.33,0.021-2.11 and 0.019-2.04μg/mL Cl2,respectively.The detection limits of the systems were 0.0020,0.0048,0.0063 and 0.0017μg/mL,respectively.In them,the RhB system has good stability and high sensitivity,and has been applied to the analysis of chlorine in drinking water,with satisfactory results which is in agreement with that of the methyl orange(MO)spectrophotometry.3.Resonance Rayleigh scattering spectrum of KI- ClO2- - rodamine dyes and its analytical applicationsIn acidic sodium acetate-HCl buffer solution containing KI,chlorite may oxidize I- to form I2,and then I2 reacts with excess I- to I3-,which combines with RhB,b-RhB,RhG and RhS, respectively,to form association particles,which give resonance scattering(RS)effect at 400 nm. The RS intensity at 400 nm of the RhB,b-RhB,RhG and RhS association particles systems is linear to chlorite concentration in the range of 0.00726-0.218μg/mL,0.0102-0.292μg/mL, 0.00726-0.145μg/mL and 0.0290-0.174μg/mL ClO2-.The detection limits of the systems were 0.00436μg /mL,0.00652μg /mL,0.0058μg /mL and 0.0145μg /mL ClO2-,respectively. Based on this,a new,simple and sensitive analysis method for the determination of chlorite in water was developed.In the four systems,the RhB system possess good stability and high sensitivity.The proposed method has been applied to the analysis of chlorite in water,with satisfactory results.4.Fluorescence analysis of trace ClO2- based on formation of rodanmine dyes association complex particlesIn acidic sodium acetate-HCl buffer solution containing KI,rhodamine B(RhB),butyl rhodamine B(BRhB),rhodamine 6G(RhG)and rhodamine S(RhS)has a fluorescence peak at 580 nm,580nm,550nm,550nm,respectively.When ClO2- exists fluorescence quenching occur. The fluorescence spectral characteristics,the influencing factors and the optimum conditions of these reactions have been investigated.For RhB,b-RhB,RhG and RhS systems,fluorescence quenching intensity is linear to the concentration of ClO2- in the range of 0.0218-0.51, 0.0218-0.304,0.0728-1.092 and 0.051-0.51μg/ml,respectively.The new,simple,sentisive fluorescence method has been applied to the determination of ClO2- in water,with satisfactory results.5.Fluorescence spectral study of rodamine dyes association particles and their application to respective determination of trace ClO2 and ClO2-A fluorescence quenching method has been proposed for respective determination of chlorine dioxide and chlorite by using rhodamine dyes.In HCl-NaAc or NH3-NH4Cl buffer solution,rhodamine S(RhS),rhodamine 6G(RhG),rhodamine B(RhB)and butyl rhodanmine B(b-RhB)respectively exhibit a maximal fluorescence peak at 550nm,550nm,576nm and 576nm.Chlorine dioxide oxidizes rhodamine dyes in acidic or alkaline solution and chlorite oxidize them only in acidic solution,which results in the decolorization of rhodamine dyes and the quenching of fluorescence peak.Under alkaline condition,concentration of ClO2 can be selectively determined by measuring the fluorescence quenching intensity.Concentration of ClO2- can be obtained by measuring the fluorescence quenching intensity that is produced by the reaction of chlorine dioxide and chlorite and by differential method.For RhS,RhG,RhB and b-RhB systems,the linear range for chlorine dioxide is 0.00840-0.53μg/mL,0.0930-3.15μg/mL, 0.215-2.610μg/mL and 0.0825-1.096μg/mL,respectively;the linear range for chlorite is 0.00950-0.711μg/mL,0.0940-2.36μg/mL,0.473-4.73μg/mL and 0.473-2.36μg/mL, respectively.In the four systems,the RhS system have good stability and high sensitivity and was chosen to determine chlorine dioxide and chlorite.It has been applied to the analysis of chlorine dioxide and chlorite in water,with satisfactory results.6.Resonance Rayleigh scattering spectral determination of trace ClO2 and ClO2- with cationic sursfactsClO2 and ClO2- oxidize I- to form I2 and it reacts with the excess I- to form I3-,which combine with a cationic surfactant such as tetrdecyldimethyl benzylammonium chloride(TDMBA),tetradecane pyridinium bromide(TPB),cetyltrimethylammonium bromide(CTMAB),tetrabutyl-ammonium iodie(TBAI)to form association particles in acidic sodium acetate-HCl buffer solution,which exhibit stronger resonance scattering effect at 320 nm,467 nm,480nm,530nm.The laser scattering indicates that the average diameter of (TDMBA-I3)n association particles was about 347 nm.The resonance scattering intensity at 467nm for TDMBA,TPB,CTMAB and TBAI systems is proportional to chlorine dioxide concentrations in the range of 0.00992-0.546μg/mL,0.0102-1.024μg/mL,0.0269-0.538μg/mL and 0.0178-1.095μg/mL,respectively.The detection limits of the systems were 0.00593μg /mL,0.00600μg/mL,0.0198μg/mL and 0.0645μg /mL ClO2,respectively.The RS intensity at 467 nm for the TDMBA,TPB,CTMAB and TBAI association particles systems is linear to chlorite concentration over the range of 0.00948-0.664μg/mL,0.0170-1.706μg/mL, 0.0474-0.855μg/mL and 0.0237-1.138μg/mL ClO2-,respectively,with detection limits of 0.00610μg /mL,0.00819μg /mL,0.0378μg/mL and 0.00949μg /mL ClO2-,respectively. Among the systems,the stability and sensitivity of TDMBA system is the best and has been used for the determination of ClO2 and ClO2- in sample.Novel resonance scattering spectral(RSS) methods for determination of chlorine dioxide and chlorite have been respectively proposed with TDMBA and the application field of the RS technology has been developed.The relationship between stability of systems and molecular structure has been primarily discussed.7.Plasmon resonance light scattering of silver nanoparticles and its analytical application to trace ClO2A plasmon resonance light scattering(PRLS)detection method of chlorine dioxide is reported based on the oxidization of silver nanoparticles(NPs)by it,in pH 9.1 ammonia-ammonium chloride buffer solutions.Silver NPs exhibit strong PRLS signals characterized at 470 nm,and can be oxidized by ClO2,which results in PRLS quenching at 470 nm.It was found that the PRLS quenching intensity is proportional to the concentration of chlorine dioxide over the range of 0.0011-0.185μg/mL,with the corresponding detection limit(3σ)of 0.00050μg/mL and the correlation coefficient of 0.9995.The method is was applied to the determination of chlorine dioxide in drinking water,with satisfactory results.The laser scattering,TEM,AAS and colored reagents were used to Characterize silver NPs and the reaction of it with ClO2.The reason of PRLS signal quenching is explained,and the relationship between UV-Vis absorption spectra and PRLS spectra is dicussed.The method is simple,convenient,cost effective,rapid and sensitive and is a innovation that RS technology is applied to the analysis of inorganics with metal nanoparticls.8.Fluorescence quenching method for the determination of trace ClO2 in water by silver nanoparticlsIn pH=9.1 NH4Cl-NH3·H2O buffuer solutions,there is a fluorescence peak at 470nm for silver nanoparticles.A fluorescence quenching take places when it was oxidized by ClO2.The intensity of fluorescence quenching is linear to the concentration of ClO2 in the range of 0.0011-0.185μg/mL.The detection limit is 0.0047μg/mL ClO2.A new fluorescence method has been proposed for the determination of ClO2 in water samples,with satisfactory results...
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