| This thesis has studied the analytical methods for determination of trace amounts of calcium and copper in cobalt and nickel matrix by Flow injection-flame atomic absorption spectrometry. This presentation includes the following parts:Part 1: Review.A review of the analytical methods for determination of trace elements in cobalt and nickel matrix. The applications of spectrophotometry, Atomic absorption spectrometry, Inductively coupled plasmas atomic emission spectrometry, Inductively coupled plasmas mass spectrometry and other methods were presented. Important trends and potentials of future development were discussed.Part2: Flame Atomic Absorption Spectrometric Determination of Trace Calcium in Cobalt and Nickel Matrix Using a Flow Injection System with On-line Pre-concentration by Co-precipitation.A flow injection on-line coprecipitation system has been coupled with an atomic absorption spectrometric system for the determination of trace calcium in bulk of cobalt and nickel matrix. Calcium was coprecipitation with 0.2g L-1 lanthanide(III)- 20 g L ' sodium carbonate solution. The analyte element was preconcentrated and separated from the bulk of the matrix with the o-phenanthroline chelate complex and the influence of bulk sulfate ion was eliminated with ethyl alcohol solution in a on-line coprecipitation system. The precipitate was collected in a micro filter cone( 2.5cm-long, 0.2cm-max i.d.,100ul-volume) , the packing material was cotton. The precipitate was dissolved with 1.2mol L-1 hydrochloric acid and introduced directly into the nebulizer-burner system of an atomic absorption spectrometer. The effect of flow rate of sample, the length of mixing tube, concentration of eluent , elution time were studied and the analytical conditions were optimized. Enrichment factor of 10.3 and Sampling frequency of 38 h-1 were obtained for calcium using 30s precipitate collection time at sample flow-rate of 2.6ml min-1. A calibration following the equation A=0.0014+0.4812C (A, Absorbance; C, concentration/ mg l-1 ) and a correlation coefficient of r=0.9994. The detection limit(3o ) was 0.01mg l-1 for calcium and the precision was 1.3% for 0.5mg l-1 Ca(n=l 1). Recoveries of calcium in sample were 96-103%. The method was successfully applied to the determination of trace calcium in high purity cobalt, high purity nickel and their compounds, alloy, electrolysis solution et al.Part3: Flame Atomic Absorption Spectrometric Direct Determination of Trace Calcium in Bulk Cobalt and Nickel Matrix Using a Flow Injection Sample Introduction System.A sample and fast method has been investigated for the determination of calcium in bulk cobalt and nickel matrix. The interference of bulk cobalt(II), nickel(II) and sulfate ion was reduced using a flow injection sample introduce system. O-phenanthroline alcohol solution was added on-line and lanthanide(III) solution was added in sample in order to eliminate the interference of cobalt(II), nickel(II) and sulfate ion. Reagent concentrations and sampling time were optimized. Sampling frequency of 116 h-1 was obtained using a sample volume 217ul. A calibration following the equation A=0.0009+0.0241C (A, Absorbance; C, concentration/ mg l-1) and a correlation coefficient of r=0.9999. The detection limit(3 o ) was 0.09mg l-1 for calcium and the precision was 1.1% for 2.5mg l-1 Ca(n=11). Recoveries of calcium in sample were 95-105%. The method was successfully applied to the determination of calcium in electrolysis solution.Part4: Flame Atomic Absorption Spectrometric Determination of Trace Copper in Bulk Cobalt and Nickel Matrix Using a Flow Injection System with On-line Sorption Pre-concentrationCopper at ng to ug levels in bulk cobalt and nickel matrix was determined by flame atomic absorption spectrometry. The analyte element was on-line preconcentrated and separated from the bulk of the matrix with thiourea chelating resin at pH=5. Copper(I) was collected in a micro conical column of thiourea resin ( 3.5cm-long, 150ug-volume) and bulk matrixes, including cob...
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