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Automatic Assignment of Emission Lines in LIBS Spectra of Steels and Soilsтезисы доклада
- Авторы: Zaytsev S., Popov A.M., Dzhedzheya G., Labutin T., Zorov N.
- Сборник: Book of Abstracts EMSLIBS 2013 Bari (Italy) September 16-20, 2013
- Серия: Euro-Mediterranean Symposium on Laser Induced Breakdown Spectroscopy
- Том: 7
- Тезисы
- Год издания: 2013
- Место издания: University of Bari Bari, Italy
- Первая страница: 208
- Последняя страница: 208
- Аннотация: The identification of emission lines in the laser-induced breakdown spectroscopy is a very difficult and time-consuming task for the experimenter. Different species can be excited to different states under various conditions (temperature and electron density) in laser-induced plasma. These conditions mainly depend on a sample matrix, wavelength of the laser beam, external pressure, and others. Manual identification of emission lines using atomic spectra databases (e.g., “NIST”, “Kurucz”) can lead to incorrect results, especially for weak spectral lines. For example, we cannot clearly to assign the weak emission line in a spectrum of high-alloy stainless steels with the line of minor (or non-certified trace) component or with the weak line of matrix elements (such as Fe, Cr, Ni, which have an enormous amount of known transitions). Even more challenging task is the identification of lines in spectra of environmental objects, such as soils or rocks. In fact, almost all existing chemical elements can present in soils, and each one can produce specific emission spectrum under certain conditions. The strong superposition of emission lines in UV-VIS spectral range is often observed. The problem is to reveal each of the peaks with specific emission line of a certain element. A possibility of automatic identification approach based on the correlation of model spectrum with experimental one for LIBS analysis of high-alloy steels was previously shown in Ref. [1] by us. More than 40 emission lines in small spectral region 393-413 nm were identified successfully. In this work, we have applied this strategy for both soils and steels. The purposes of the present investigation were the widening of recognized spectral region, the verification of existence of LTE in plasma and the comparison of the identification procedure implemented for different excitation conditions in plasma. For identification of lines in the spectra of soils, we have sufficiently expanded set of used lines by including the spectral information of the matrix and minor elements of soils to our calculations. We tried different weighting procedures for attribution of the peak with the certain line, involving the values of transition probabilities and closeness to the center of observed peak. Suggested approaches provide a fast and accurate identification of the emission lines in laser-induced plasma of the objects of different origin (such as soils and steels). [1] Labutin T. A., Zaytsev S. M., Popov A. M., Anal. Chem. (2013) Vol. 85, P.1985–1990.
- Добавил в систему: Лабутин Тимур Александрович