| In this paper the methods of ion chromatography and ion-pair reversed phase high performance liquid chromatography coupled with evaporative light scattering detector for quantitative analysis of fosetyl-aluminium in technical or formulated were estab-lished on the base of preparation and analysis of fosetyl-aluminium pure samples for instrument analysis. The residues of aluminium in cucumber and the leaf samples after applying fosetyl-aluminium on cucumber planting in plastic house in Changchun city were analyzed and evaluated. In addition, all ingredients of fosetyl-aluminium techni-cal were analyzed.Fosetyl-aluminium technical made in China was purificatied with the method of washing three times by redistilled water and vacuum filtration whose impurities are mostly phosphite, sulfate and the prepared pure sample of fosetyl-Al could satisfy the demand of ion chromatography analysis. The pure fosetyl-aluminium was determined by the method of iodimetry and ion chromatography, and its content was above 99.0 %. The influence of familiar anions and the concentration of eluent on the separation of fosetyl-Al were studied using DIONEX AS 14 and AS 9 analytical columns.The method of quantitative analysis of fosetyl-aluminium technical, fo-setyl-aluminium formulated and their impurities by ion chromatography with elec-tronic conductivity detector, AS 9 column, Na2CO3 solution as eluent was established. The samples dissolved in the water with ultrasonic oscillating for 30 minutes. The re-coveries of two fortification levels were 100.1 - 100.2 % with RSD of 0.31 %. The ac-curacy and the precision of the method satisfied the demand of macro analysis. The result of samples determined was satisfying. The method of ion chromatography is simple, accurate, rapid, and could determine a number of samples simultaneously compared with the method of iodimetry.In this paper, the quantitative analysis method of reversed phase high performance liquid chromatography with n-hexylamine as ion-pairing reagent was established for the first. Fosetyl-aluminium presented good linearity in the range of 50 - 800 mg﹒L-1. The LOD was 100 ng. The average recovery of the method was 100.3 - 100.6 % with RSD of 0.63 %. The method of ion-pair reversed phase high performance liquid chro-matography is more practical in the way of produce and quality test of technical or formulated on the base of application of evaporative light scattering detector increas-ingly.In this thesis, the method of wet digestion-graphite atomic absorption spectrome-try was established by which the background content and the final residues of alumin-ium in cucumber and the leaves after applying fosetyl-aluminium were determined. The linearity rang was 0 - 400μg﹒L-1, r was 0.991 3. The LOD of aluminium was 62.4 pg. The recovery of aluminium determined in cucumber was 92.1– 98.7 % with RSD of 4.8 - 5.1 % and the recovery of aluminium determined in the leaves was 89.0– 100.1 % with RSD of 13.9 - 17.6 %. The accuracy and the precision of the method sat-isfied the trace analysis requirements. The background content of aluminium in cu-cumber blank samples was 5.0 - 8.7 mg﹒kg-1, average content was 6.8 mg﹒kg-1, and in the leaf blank samples was 187.5 - 223.6 mg﹒kg-1, average content was 201.6 mg﹒kg-1. Fosetyl-aluminium 80 % WP (high dose 5 640 g﹒hm -2, active ingredients) was sprayed for 2 - 3 times in the leaves one week interval. The final residue of alu-minium in cucumber samples was 6.98 - 9.35 mg﹒kg-1. According to the relevant standard, the cucumber was safe for food. The highest final residues of aluminium in the leaves was 339.53 mg﹒kg-1. The results showed that the accumulation of alumin-ium from fosetyl-aluminium in the leaves was obvious compared with background content of aluminium in the leaf blank samples 187.5 - 223.6 mg﹒kg-1 which is con-cerned to the doses and times of pesticide application.The UV spectra, IR spectra, NMR spectrum and mass spectrum of fo-setyl-aluminium were obtained in the paper. These spectrograms further characterized the chemical structure of fosetyl-aluminium. All components of fosetyl-aluminium technical made in china were determined for quantitative analysis by ion chromatog-raphy. The impurities more than 0.1 % were phosphite ion, sulfate ion, ammonium ion in addition to the main ingredient and moisture that was 4.2 - 8.3 %, 2.7 - 3.7 % and 1.2 - 1.3 % respectively.
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