| With the rapid development of China’s economy, it is the severe shortage of water resources, continuous expansion of industrial parks, increasing pollutants that have exacerbated the problems of aquatic environmental pollution tremendously.According to statistics, Water pollution is severe in more than 90% of cities of the country and the water quality is below national or local standards in more than 50% of the main urban and downtown areas. The pollution has been spreading from the city to neighboring rural areas, infiltrated from the surface gradually to the underground. The nutrient enrichment has appeared in most rivers, lakes. At present, the common factors that influence water quality of aquatic environments are the index of ammonia nitrogen, total phosphorus, potassium permanganate and some trace elements(such as heavy metal ion) which accounts for the majority of those factors and includes a great many sorts. It is of great importance to determine the contents of trace elements in aquatic environments, because the higher or lower contents of these trace elements may impose vile impact on ecosystem and are related to human health issues directly or indirectly.Methods to determine the environmental pollutants in aquatic environment are colorimetry, chemiluminescence, atomic spectrometry, mass spectrometry, chemical and biological sensor method, catalytic kinetic spectrophotometry, neutron activation analysis, high performance liquid chromatography, fluorescence analysis. Whereas, due to the following merits: 1)high sensitivity, wide linear range; 2)easy-operated instruments, good reproducibility; 3) better selectivity, fluorescence analysis has been widely adopted in the determination of environmental pollutants both at home and abroad, especially in the determination of contents of heavy metal ions and other trace elements.The paper will deal with the method of fluorescence analysis to determine heavy metal ion of antimony, copper and environment pollutant-fluoride ion in the aquatic environments. The following are details:In B-R solution, the fluorescent intensity decreases by various dgrees when Sb(III) solution of different concentration is added to morin fluorescence solution and when the stimulating wavelength and emitting wavelength are 417 nm and 496 nm this phenomenon is most obvious, based on which a new method can be developed for the determination of trace Sb(III). When the concentration of trace Sb(III) is within 0.004-0.06μg/m L, it is proportional to ΔF-variable of morin fluorescence intensity, the detection limit is 9.80×10-4 μg/m L. Of 12 replicate measurements for 0.02μg/m L trace Sb(III) solution, the relative standard deviation is 0.31%. The method can achieve satisfactory results with the recovery rate between 98.4%~103.6% when it is used in different environmental water samples for determination of trace Sb(III).When Cu(II) solution of different concentration is added to morin fluorescent solution with sulfuric acid and sixteen-alkyl-three methyl bromide, the fluorescent intensity varies by different degrees and when the stimulating wavelength and emitting wavelength are 417 nm and 497 nm, this phenomenon is most obvious, based on which a new method to determine trace Cu(II) can be developed. It is found that the concentration of trace Cu(II) is proportional to ΔF variable of morin fluorescence intensity when it is within 0.004-0.02μg/m L, the detection limit is 3.9×10-4μg/m L. Of 12 replicate measurements for 0.012 μg/m L trace Cu(II) solution, the relative standard deviation is 0.76%. The method can achieve satisfactory results with recovery rate of 96.1%~102.9% when it is used in different environmental water samples for determination of trace Cu(II).In ammonia-ammonium chloride buffer solution, trace F- can enhance the intensity of fluorescence of morin obviously, based on which a new method has been developed for the determination of trace F-. When the stimulating wavelength and emitting wavelength are 464 nm and 554 nm, this phenomenon is most obvious. When the concentration of trace F- is within 0.04~0.36μg/m L, it is proportional to ΔF-variable of the morin fluorescence intensity, the detection limit is 0.02μg/m L. Of 12 replicate measurements for 0.12μg/m L trace F- solution, the relative standard deviation is 0.5%. The method can achieve satisfactory results with the recovery rate of 91.7%~108.3% when it is used in different environmental water samples for determination of trace F-. |
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