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The impact analysis of different environments on the fluorescence emission spectrum of pesticides is critical in detecting the concentration of pesticides. In this paper, three kinds of pesticides, carbendazim, carbaryl and fuberidazole, were selected as the research objects. Under different environment, such as different pH values and the presence of different common anion or cation, three-dimensional fluorescence spectral emission (EEM) characteristic of pesticides were analyzed. The experimental results showed that the primary fluorescence peaks for three kinds of pesticides were at λex/λem=280/300, 310/340 and 280/335 nm (respectively); Carbendazim and fuberidazole had a secondary peak at 245/305 nm (PeakB) and 250/340 nm (PeakB). We can come to the conclusion that with the change of pH value, the characteristic of fluorescence emission of carbendazim and fuberidazole is similar. We can find that the fluorescence intensities of carbendazim and fuberidazole were enhanced with the declining of the solution acidity or alkalinity and the fluorescence intensity of carbaryl had not changed with the declining of the solution acidity, but it increased with the declining of the solution alkalinity; the fluorescence emission spectra of the three kinds of pesticides had good fluorescence characteristics with the scope of the pH varying from 6.16 to 7.4. Twelve common ions in water (CO2-3，SO2-4，NO-3，Cl-，HPO2-4，HCO-3，Mg2+，Zn2+，NH+4，Na+，Ca2+，K+) had no significant effect on fluorescence emission characteristics of carbendazim and fuberidazole. The fluorescence intensities were seriously influenced by Fe3+ and Cu2+. The results showed that the pesticides fluorescence intensities were decreased with the ion concentration increasing. It was necessary to consider the quenching effects on pesticides of Fe3+ and Cu2+for the analytic results. The obtained results provided the basic research for improving the accuracy of the heterocyclic pesticides measurement in water.

Chlorophyll concentration and photosynthesis activity fluorescence parameters of Chlorella pyrenoidosa stressed by different concentrations of Cd2+ were measured based on algal growth inhibition tests and photosynthetic activity inhibition tests. The relationship between the algal photosynthetic activity inhibition rate and 96 h inhibition rate of specific growth rate at different Cd2+ stress times was studied by sigmoidal curve fitting and one-way ANOVA analysis. The result shows that S function relevance exists between the algal photosynthetic activity inhibition rates for 48 h, 53 h, 72 h, 77 h and 96 h respectively and 96 h inhibition rate of specific growth rate (R2 > 0.95). Consequently, EC10 (10% effective concentration) after 48 h and 53 h inhibition in photosynthetic activity inhibition tests could be used to represented EC50 (50% effective concentration) in 96 h algal growth inhibition tests for evaluating the Cd2+ toxicity. Dose-response relationships between the algal photosynthetic activity inhibition rates after 48 h and 53 h inhibition and Cd2+ toxic equivalency quantity were further analyzed. The method provided a rapid and viable new thought to monitoring single Cd2+ toxicity in lab and early warn integrated toxicity of pollution in water.

Three dimensional excitation-emission fluorescence spectra, chemical oxygen demanding (COD) and dissolved organic carbon (DOC) for water samples from Science Island, Chaohu Lake and Taihu Lake were determined. The COD values of the samples from Chaohu Lake were linearly correlated with the DOC values. Relationships of dissolved organic matter (DOM) concentrations determined by three dimensional excitation-emission fluorescence matrix (3DEEM), observed protein-like fluorescence intensity (Ipro-like) and humic-like fluorescence intensity (Ihum-like) to the chemical oxygen Demanding (COD) for all the samples from different sources were analyzed. Results indicated that DOM concentrations measured by 3DEEM and COD for the water samples from Science Island were well linearly related (r = 0.82172), and the linear relationships also existed between Ipro-like. and COD (r = 0.84651), as well as Ihum-like and COD (r = 0.83689). However, for the water samples from Chaohu Lake and Taihu Lake, no linear relationships existed. The cause of the above difference between the water samples from Science Island and those from Chaohu Lake and Taihu Lake, and the feasibility and the limits of the integrated organic pollution measurement using three dimensional excitation-emission fluorescence spectroscopy were further discussed.

A sort of analytical method of fast diagnosis of organic matter in water is discussed. The total luminescence spectra (TLS) of water samples in combination with laser induced fluorescence (LIF) measurements using 532 nm wavelength excitation source were measured in the laboratory. The spectra of dissolved organic matter (DOM) and chlorophyll a (Chl a) were pointed out and obtained with spectral fluorescence signature (SFS) technique. The spectrum of water Raman scattering and fluorescence of DOM and Chl a were separated from TLS with fiting Gaussian of the least squares method, and a high correlation coefficient excelling 0.996 4 was obtained. The results indicated the possibilities of water quality monitoring in real time and on line based upon SFS technique and fitting Gaussian of the least squares method.

In the experiment a frequency doubled radiation of Nd:YAG laser was used for excitation at 532 nm. The fluorescence spectra of dissolved organic matter (DOM) and chlorophyll a (Chl-a) in several types of water samples with laser-induced fluorescence (LIF) measurements using a 532 nm wavelength excitation source were measured in the laboratory, and the spectral characteristics of DOM and Chl-a were analysed. The characteristics of turbidity were investigated by measuring the amount of scattering light of suspended particles in the water volume. The curve of scattering intensity against corresponding turbidity of SiO2 is showed. The possibilities of water quality monitoring based upon the fluorescence spectral characteristics of contaminations and the turbidity by means of LIF method.

The fluorescence spectra of dissolved organic matter (DOM) in several types of water samples in combination with laser-induced fluorescence (LIF) measurements were measured in the laboratory, and the spectral characteristics of DOM were analysed. The curve of normalized fluorescence intensity against corresponding concentration of humic acid is showed. The results demonstrate the possibilities of water quality monitoring based upon fluorescence spectral characteristics of DOM by means of LIF method.