| As theworld economy was rapid developed and the population grew, the attention focused today on the environment. And the heavy metal pollution was a source of environmental contamination. The research on rapid, sensitive and accurate determination of heavy metal was very important for environment.Atomic fluorescence spectrometry (AFS) is famous for its high sensitivity, low detection limit and little memory effect, which is used for determination of As, Sb, Hg and so on. Trend for the development of modern AFS, the author studied the atomic fluorescence mercury analyzer and multi-elements analysis methods. The high sensitive atomic fluorescence mercury analyzer and solid sampling device have been designed and developed, dual chemical vapor generation system and atomic fluorescence multi-elements analysis methods have been studied.The dissertation includes the following seven chapters:1. IntroductionThis chapter presented the history of the development, basic principles, equipment and structure, and the application of atomic fluorescence techniques. The author reviewed the development tendency for AFS was also presented.2Research on high sensitive atomic fluorescence mercury analyzerBy fiber optic technology, self-designed darkroom atomic device and gold amalgamation enrichment devices, the author developed the atomic fluorescence mercury analyzer. The results indicated the instrument's main technical parameters had already reached the level of the congener domestic and foreign products, and some of technical parameters were better than them. And it has high sensitivity, low detection limit and simple sample pretreatment for direct analysis of liquid and solid samples. The author developed the fiber optic technology and the darkroom to the atomic fluorescence instrument for the first time, reduced effectively the loss of light propagation in air, descended the interference of the external light and made it compact in the design. With the application of enrichment devices, it effectively not only eliminated matrix interference, but also increased the sensitivity of determination.3. Determination of ultra trace mercury by atomic fluorescence mercury analyzer in waterBy the atomic fluorescence mercury analyzer, the author successfully determined ultra trace mercury in pure water, tap water and ground water. Linear range was0.005-1.000ng/mL, the Correlation coefficient(r) was more than0.999, detection limit is less than0.5x10-12ng/mL, and the recovery was from95%to98%. Thus, it was a rapid, accurate and high sensitive method of ultra trace mercury analysis in water.4. Direct determination of mercury in soil by atomic fluorescence mercury analyzerBy the fluorescence mercury analyzer, the author designed automatic injector for solid samples to achieve direct solid sampling, and successfully detected Hg in different soil samples (GBW07402,GBW07423,GBW07401,GBW07404,GBW07406,GBW07411, GBW07405and GBW07302). The Correlation coefficient (r) was more than0.998, the detection limit is less than0.003ng, the relative standard deviation (R.S.D.) was less than4.0%and the recovery was103%. The method increased the speed of sample analysis and reduced the cost of determination, which was very rapid, accurate for ultra trace mercury analysis in soil.5. Solid sampling-simultaneous determination of arsenic and antimony by AFSThe author first proposed the low-temperature heat release for solid samples for AFS. The solid sampling device was designed, and connected to multi-channel atomic fluorescence spectrometer successfully. The steps were online operated that release, absorption, chemical vapor generation, determination and purge. According to volatile characteristics of the elements halide of AFS measurement, the author added NH4Br into solid samples for reducing the heat release temperature, and achieved rapid and quantitative release target elements at low temperature. The author succeeded in direct solid sampling and simultaneous determination of trace As and Sb in soil and rock. The detection limit of As and Sb was respectively0.009and0.004μg/g, the least detection concentration was respectively0.028and0.013, and the Correlation coefficient (r) was all more than0.998.6. Simultaneous determination of arsenic, antimony, selenium and mercury by AFSThe author studied and optimized experimental conditions of simultaneous determination of As, Sb, Se and Hg by multi-channel atomic fluorescence spectrometer, including sample preparation, chemical vapor generation and atomic fluorescence detection. The author achieved to determinate simultaneously As, Sb, Se and Hg in traditional Chinese medicine by AFS. The detection limit of As, Sb, Se and Hg was respectively0.051,0.034,0.050and0.0058ng/mL, the Correlation coefficient (r) was all more than0.998, and the relative standard deviation (R.S.D.) was all less than1.5%.7. Simultaneous determination of lead, tin and cadmium by AFSThe author proposed dual chemical vapor generation system for the first time for AFS (The system1included Cd and part of the Sn chemical vapor generation, and the system2 included Pb and part of the Sn chemical vapor generation). The author achieved to determinate simultaneously Pb, Sn and Cd in biological samples by dual chemical vapor generation system chemical and multi-channel atomic fluorescence spectrometer. And the experimental conditions of simultaneous determination of Pb, Sn and Cd were studied and optimized. The method had high sensitivity and little memory effect. The Correlation coefficient (r) was all more than0.996, the relative standard deviation (R.S.D.) was all less than3.5%, and detection limit of Pb, Sn and Cd was respectively0.071,0.052and0.0002ng/mL.
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