Application of an atomic-emission spectroscopy method for estimating stoichiometric relations of elements in high-temperature superconducting materials based on Bi-Sr-Ca-Cu-O

An application of the method of atomic-emission spectroscopy for the estimation of stoichiometric ratio of elements in high temperature superconductive materials based on Bi-Sr-Ca-Cu-O is described. Possibilities for realization of optimal conditions of registration of emission spectrum to get minimal error of determination of stoichiometric ratio of elements in HTSC-systems with the method of atomic emission spectroscopy on an example of Bi-Sr-Ca-Cu-O are investigated. The investigations have been conducted on the installation with the arc of alternative current and spectrograph DFC-13. 10 mg of probe admixture with the coal powder (1:1) was placed into thin wall electrode with the external diameter 4 mm. The value of the current in the arc was 15 A for the distance between electrodes 3 mm. The most appropriate for the analysis of considered HTSC system were the following spectral lines: Bi I 307.67 nm; Sr I 333.00 nm; Ca II 318.13 nm; Cu I 306.34 nm. The minimum error of the elemental content determination is observed for the registration of spectrum in the interval of time exposition 15-45 s. The method of atomic emission spectral determination of stoichiometric coefficients of elements in the HTSC system Bi-Sr-Ca-Cu-O with relative standard deviation of the results of analysis not more than 0.07 for all coefficients determined. 9 refs., 2 figs., 3 tabs