| Popis: |
According to the commonly used method of analysis with ICP-AES in geochemistry, to study the influence factors of interference from the analysis results, standard soil substances were selected to be the calibration curve of work, and the same method of digestion with soil samples was used to balance and eliminate the matrix interference. The concentrations of major and minor elements in soil samples were measured; the relative deviation of the results was compared under conditions of soil matrix and non-soil matrix interference; the relations and laws were being analyzed. The relative deviation (RE%) of testing results under non-soil-matrix interference were found floating around zero, the ratios of positive deviation and negative deviation were almost the same. Excluding the factors of spectral interference, the method of matrix matching can effectively eliminate the effects of matrix interference on soil. It was found that the analysis results of major elements, such as Al, Ca, Fe, Mg, P, Ti and Ba, were influenced negatively greatly under the condition of soil matrix interference, The maximum deviation of Mg 279.5 nm was up to -14.49%. The degree of influence ranking showed as Ti, MgP, FeCa, BaAl. However, there is no obvious effect on other elements, including Na, Cr, Cu, V, Li, Mn, Ni and Sr. Contrary to the original ideas, the matrix interference effected greatly on the results of elements of high content, nevertheless, the effects on minor elements were not significant. As to the comprehensive matrix interference , the large proportion of interference from component self-content appeared of elements of Ca and Mg, because obvious linear correlation was found between component self-content and the relative deviation of the testing results of Ca and Mg. But no linear trend appeared between the self-contents of other elements and the results of matrix interference, indicating that the influence weight from self-content of other elements was very small. It was very important to select the right spectral lines, and remove the factors of interference to determinate the results of measurement. Factors and rules of interference effect has always been the research topic by all of scholars in the research field of ICP spectrum. On the guidance of above research results, the spectral lines will be selected and the accuracy judged reasonably, when soil samples being analyzed by ICP-AES. |
