Studies And Application Of Indirect Atomic Absorption Spectrometric Analysis

This paper consists of six chapters. In chapter 1, the application and progress of indirect atomic absorption spectrometry (AAS) is reviewed, including analysis principles, application of FJA-AAS indirect method and application of indirect AAS in analysis. 160 references are cited. In chapter 2, a method was described for the indirect determination of phosphorus and the direct determination of magnesium in vegetables by flame atomic absorption spectrometry (FAAS). After the precipitation of magnesium arnmonium phosphate was obtained with the reaction of magnesia reagent and phosphate in ammoniacal solution, the precipitation was dissolved in I-1N03 and magnesium content in solution was determined by FAAS. The phosphorus content was calculated with the content of magnesium. The contents of magnesium and phosphors in different parts of vegetables were successfully determined using the proposed method with satisfactory results. In chapter 3, a novel method was developed for the indirect determination of iodide by FAAS. Precipitation (GuI) obtained with the reaction of Cu~ with 1 was dissolved in Na2S2O3. Copper content in the solution was determined by FAAS and the iodide content was calculated using the content of copper. The proposed method was applied to determination of iodide in iodized table salt, tablet cydiodini and noir. In chapter 4, an indirect FAAS method for the determination of glutamic acid in condiment was investigated. After adding copper phosphate suspension into sample solution to react with glutamic acid, the unreacted reagent was subsided using centrifuge and copper is detected in solution by FAAS. The proposed method applied to determination of glutamic acid in condiment with satisfactory results, which gave a recovery range of 96.6%A02.1% with a relative standard deviation of 0.8%. ?? In chapter 5, on the basis of exchange reaction of 8042 with BaCrO4 in the water-ethanol-ammonia medium, an indirect method for the determination of sulfate in table salts and water by flame atomic absorption spectrometry (FAAS) has been developed. Various conditions affecting the quantitative determination of S042 were investigated and optimized. The results obtained by this method are consistent with those obtained by ion-chromatography (IC). In chapter 6, a method was developed for the determination of vitamin B12 by FAAS. The experimental conditions affecting separation and determination of cobalt and vitamin B12 were investigated and optimized. The separation of vitamin B12 and inorganic cobalt was carried out using filtration chromatography on a cation exchange column. The proposed method was applied to determination of vitamin B12 in pharmaceutical dosages and injections with satisfactory results.