| The investigation on the powerful laser induced micro-plasma by the radiation focused on a solid surface plays an important role in super-conduct films, nanometer materials, laser isotope separations, medicine, biology, and other industrial applications. Elemental analysis based on the emission from plasma generated by focusing a powerful laser beam on a solid sample surface is known as laser-induced breakdown spectroscopy (LIBS). When the power density of laser on the sample surface is high enough, the sample is vaporized, and the neutral and ionic species are formed in excited states. The spectral lines emitted from these species can be used to determine the sample composition. The wavelengths observed are characteristic of the individual elements present in the sample, and their intensities are related to the concentration of the corresponding species in the sample. LIBS has power potential to be used to detect trace elements in the sample matrix that include gases, aerosols, and liquids. The high sensitivity of the technique, the minimal sample preparation that it requires, and its suitability to remote measurements are generally concerned by scientific researchers. The focus of this paper will be on solid sample.In chapter 1, the basic feature and temporal characteristics of laser induced plasma and LIBS are introduced. The basic principle of LIBS as a quantitative analysis method is also presented.In chapter 2, the property of LIBS in Cu-Pb alloy and the determination of the optimum experimental condition in elemental quantitative analysis are investigated. The main contents are as follows: (1) some characteristic emission lines of neutral atoms in excited states are identified. (2) The effect of rotary target and fixed one on LIBS' intensity is studied. It is shown that the spectra intensity is stable when the rotary target is used. But in the case of fixed target the spectra intensity become weak with the target long exposed to the laser radiation. (3) Influence of laser power density on atomic emission intensity is investigated. At the fixed laser energy, the results show that the line intensity and stability can be enhanced if the focus of lens is set into the sample. (4) Time resolution property of LIBS is studied. At the 4us delay, the signal-to-background ratio is more proper. (5) The intensity and S/B of LIBS areinvestigated in detail at the different buffer gas, gas pressure, and laser power. The results show that under the 120 mJ laser energy, for Ar the best S/B is at 200 Torr pressure, but for Air at 100 Torr and He at 300 Torr. Duration of atomic spectra in Ar is longer than that in Air. Finally, parts of the mentioned results are discussed.On the basis of the results given in Chapter 2, in chapter 3, the calibration curves for the impurity elements such as Bi, Ni and Fe are obtained in 4 kinds of the buffer gases under the optimized experimental conditions and parameters. The main contents are as followings: (1) the rules of choosing characteristic lines of Fe and Ni elements in the Cu-Pb alloy are investigated; (2) the characteristic line of the impurity element and that of the reference element makes up a line pair. The intensity ratio of the line pair measured as an Y-axis and the corresponding concentration ratio as X-axis, Calibration curves for composition analysis is fitted at the 4 kinds of buffer gases. The discussion of the calibration curves concludes that the Calibration curves with the Ar buffer gas are more accurate than those with the others; (3) the curve characteristics are discussed and concluded.
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