Laser-induced breakdown spectroscopy(LIBS) is a versatile tool for both qualitative and quantitative analysis.In this paper,LIBS combined with principal component analysis(PCA) and support vector machine(SVM) is applied to rock analysis.Fourteen emission lines including Fe,Mg,Ca,Al,Si,and Ti are selected as analysis lines.A good accuracy(91.38% for the real rock) is achieved by using SVM to analyze the spectroscopic peak area data which are processed by PCA.It can not only reduce the noise and dimensionality which contributes to improving the efficiency of the program,but also solve the problem of linear inseparability by combining PCA and SVM.By this method,the ability of LIBS to classify rock is validated.
Laser-Induced Breakdown Spectroscopy(LIBS) has been demonstrated to be an effective method for slag analysis.In order to better clarify the nature of the plasma generated from a slag sample,an Nd:YAG pulse laser at 1064 nm wavelength was used to ablate the slag sample in air.The temporal and spatial evolutions of plasma parameters,including emission intensity,electronic density and plasma temperature,have been studied.It is shown that the electron density and plasma temperature drop off rapidly with the delay time as a result of plasma expansion and cooling.It has been found that the electron density of the whole plasma is close to that of the center regions in the plasma.The results of the spatial distributions on the two-dimensional plane have shown that there is a big region with lower electron density values caused by the recombination process in the center of the plasma.The maximum of the plasma temperature takes place at the regions close to the target,and the border of the plasma front-head has higher plasma temperatures than that of the center part.
为了减少导致激光的故障光谱学(解放) 的影响，到炉渣部件，使用血浆图象的不可分的紧张被建议的一个正规化方法和有炉渣样品的一系列实验的定量分析的试验性的参数变化被执行。Mg II 279.55 nm， Ca II 396.85 和 Ca 我 422.67 nm 作为参考团部分的分析的线，和分析曲线被选择对光谱线紧张被建立。与为血浆图象的边抽取的集合阀值的增长，决心系数和分析曲线的相对标准差逐渐地被改进并且当阀值等于时，到达了最佳值 10 000。没有正规化，与结果作比较并且由整个系列区域使正常化，相关性在之间光谱在由血浆图象的不可分的紧张使正常化以后，线紧张和集体部分能高效地被提高。有 Ti 合金样品的确认实验进一步证实了上面提及的结论。
