| Nowadays, in face of the world people increasing and the living level constantly enhancing, people are concerned about our environment protection. Only if we make a real time,quickspeed,accurate detection for pollutant species, reliable data can be supported for environment protection. So we studied the porous optics probe for mercury and the fast qualitative test paper for the familiar contamination nitrate,nitrite.The first part is the review of the literature. We summarized a variety of methods of measuring the concentration of mercury, particularly emphasizing on mercury sensor especially the research and development of optics and optics fiber sensor for mercury, in addition, we put forward the conceive of our research.The second part emphasized on studying the porous optics probe for mercury. We separately selected Methyl methylacryte(MMA) and the mixture of Methyl methylacryte(MMA),Methylacrylate as the monomer, Diethylene glycol dimethacrylate(DGDM) as cross-linking agent. The probe was prepared by a copolymerization technique. At the same time, we covalently rooted N-vinylcarbazole sensitive agent in the probe. We investigated the effects of mercury and pH on response character of the probe with different interpolymerization materials' proportion, different porosity and different amount of indictor. Under the condition of optimum compounding ration, the linear respond range of the probe were 2.0×10－4～1.0×10－3mol/L and 1.0×10－5～5.0×10－3mol/L, and the detection limit were 1.27×10－5mol/L'6.5×10－7mol/L. In addition, the stability,reversibility,responsive time of the probe and the interferent were also studied. In spite that these porous sensing probes could not meet the demand of the determination practically, our research would provide a new method for mercury fiber optical chemical sensor probes' design, provide a new clew in situ.,continuous,automatic,high sensitive environment detection.In the third part, a test paper method had been established for the determination nitrite and nitrate. The assay typically relied on the diazotization of sulfanilamide byacidized nitrite with the subsequent coupling reaction of N-(1-Naphthyl) ethylenediamine providing a highly coloured azo chromophore from which the concentration of nitrite can be assessed. The reaction can be used directly for the determination of nitrite, but nitrate required the incorporation of a reduction step prior to commencing the assay. We selected solid acid,aromatic amine and chromophoric agent and examined the effect of the reactive temperature and time. We confirmed the best proportion and sensitivity. The reactive temperature had no effect on the test paper reaction. As the temperature was higher, the drying time was shorter. Two minutes after showing color, the color attained the deepest and kept stabilization in fifty minutes. The test paper kept stabilization in the long time(more than five month). The detection limit of nitrite was 0.4ppm. The prospects for the test paper in nitrate and nitrite analysis were very promising because of its advantages, such as facility, convenience and rapidness. It would provide a convenient determination method for the food inspection department. |
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