光谱学与光谱分析
光譜學與光譜分析
광보학여광보분석
SPECTROSCOPY AND SPECTRAL ANALYSIS
2015年
2期
309-314
,共6页
王寅%赵南京%刘文清%余洋%方丽%孟德硕%胡丽%张大海%马明俊%肖雪%王煜%刘建国
王寅%趙南京%劉文清%餘洋%方麗%孟德碩%鬍麗%張大海%馬明俊%肖雪%王煜%劉建國
왕인%조남경%류문청%여양%방려%맹덕석%호려%장대해%마명준%초설%왕욱%류건국
激光诱导击穿光谱%阻尼最小二乘法%特征光谱分离提取
激光誘導擊穿光譜%阻尼最小二乘法%特徵光譜分離提取
격광유도격천광보%조니최소이승법%특정광보분리제취
LIBS%DLS%Characteristic spectral lines separation and extraction
近年来，激光诱导击穿广谱技术发展迅速。作为一种用于物质成分探测的新技术，它具有简单、快速、无需复杂样品制备、多种元素同时检测等优点，可实现待测样品物质成分现场、在线的检测，在很多领域都极具应用前景。激光诱导击穿光谱特征谱线的分离拟合提取是光谱特征识别与后续元素浓度定量反演研究的基础。为实现激光诱导击穿光谱重叠特征谱线的有效分离拟合提取，采用阻尼最小二乘法，分析并确定了迭代前的初始拟合参数值，实现了在重叠特征谱线情况下对某火力发电厂粉煤灰中的铬元素特征谱线的分离提取。阻尼最小二乘法基于高斯－牛顿迭代，在迭代步长中引入阻尼因子，在迭代的过程中根据每一步迭代后所反馈的信息动态的调整迭代步长，从而有效防止了迭代的发散，保证了迭代的快速收敛，最终使得元素特征谱线拟合提取的效果更佳、所得到的特征谱线强度值更准确。分别采用阻尼最小二乘法和最小二乘法对不同浓度的样品中铬元素特征谱线进行分离拟合提取并给出特征谱线的强度值，作出特征谱线强度值关于元素浓度的定标曲线并对比两种方法所得结果的线性相关性。结果表明，阻尼最小二乘法所得结果的线性相关性更高，该方法稳定、可靠，适用于激光诱导击穿光谱重叠特征谱线的分离拟合提取。
近年來，激光誘導擊穿廣譜技術髮展迅速。作為一種用于物質成分探測的新技術，它具有簡單、快速、無需複雜樣品製備、多種元素同時檢測等優點，可實現待測樣品物質成分現場、在線的檢測，在很多領域都極具應用前景。激光誘導擊穿光譜特徵譜線的分離擬閤提取是光譜特徵識彆與後續元素濃度定量反縯研究的基礎。為實現激光誘導擊穿光譜重疊特徵譜線的有效分離擬閤提取，採用阻尼最小二乘法，分析併確定瞭迭代前的初始擬閤參數值，實現瞭在重疊特徵譜線情況下對某火力髮電廠粉煤灰中的鉻元素特徵譜線的分離提取。阻尼最小二乘法基于高斯－牛頓迭代，在迭代步長中引入阻尼因子，在迭代的過程中根據每一步迭代後所反饋的信息動態的調整迭代步長，從而有效防止瞭迭代的髮散，保證瞭迭代的快速收斂，最終使得元素特徵譜線擬閤提取的效果更佳、所得到的特徵譜線彊度值更準確。分彆採用阻尼最小二乘法和最小二乘法對不同濃度的樣品中鉻元素特徵譜線進行分離擬閤提取併給齣特徵譜線的彊度值，作齣特徵譜線彊度值關于元素濃度的定標麯線併對比兩種方法所得結果的線性相關性。結果錶明，阻尼最小二乘法所得結果的線性相關性更高，該方法穩定、可靠，適用于激光誘導擊穿光譜重疊特徵譜線的分離擬閤提取。
근년래，격광유도격천엄보기술발전신속。작위일충용우물질성분탐측적신기술，타구유간단、쾌속、무수복잡양품제비、다충원소동시검측등우점，가실현대측양품물질성분현장、재선적검측，재흔다영역도겁구응용전경。격광유도격천광보특정보선적분리의합제취시광보특정식별여후속원소농도정량반연연구적기출。위실현격광유도격천광보중첩특정보선적유효분리의합제취，채용조니최소이승법，분석병학정료질대전적초시의합삼수치，실현료재중첩특정보선정황하대모화력발전엄분매회중적락원소특정보선적분리제취。조니최소이승법기우고사－우돈질대，재질대보장중인입조니인자，재질대적과정중근거매일보질대후소반궤적신식동태적조정질대보장，종이유효방지료질대적발산，보증료질대적쾌속수렴，최종사득원소특정보선의합제취적효과경가、소득도적특정보선강도치경준학。분별채용조니최소이승법화최소이승법대불동농도적양품중락원소특정보선진행분리의합제취병급출특정보선적강도치，작출특정보선강도치관우원소농도적정표곡선병대비량충방법소득결과적선성상관성。결과표명，조니최소이승법소득결과적선성상관성경고，해방법은정、가고，괄용우격광유도격천광보중첩특정보선적분리의합제취。
In recent years,the technology of laser induced breakdown spectroscopy has been developed rapidly.As one kind of new material composition detection technology,laser induced breakdown spectroscopy can simultaneously detect multi elements fast and simply without any complex sample preparation and realize field,in-situ material composition detection of the sample to be tested.This kind of technology is very promising in many fields.It is very important to separate,fit and extract spectral fea-ture lines in laser induced breakdown spectroscopy,which is the cornerstone of spectral feature recognition and subsequent ele-ments concentrations inversion research.In order to realize effective separation,fitting and extraction of spectral feature lines in laser induced breakdown spectroscopy,the original parameters for spectral lines fitting before iteration were analyzed and deter-mined.The spectral feature line of chromium (CrⅠ:427. 480 nm)in fly ash gathered from a coal-fired power station,which was overlapped with another line(FeⅠ:427. 176 nm),was separated from the other one and extracted by using damped least squares method.Based on Gauss-Newton iteration,damped least squares method adds damping factor to step and adjust step length dynamically according to the feedback information after each iteration,in order to prevent the iteration from diverging and make sure that the iteration could converge fast.Damped least squares method helps to obtain better results of separating,fitting and extracting spectral feature lines and give more accurate intensity values of these spectral feature lines.The spectral feature lines of chromium in samples which contain different concentrations of chromium were separated and extracted.And then,the intensity values of corresponding spectral lines were given by using damped least squares method and least squares method sepa-rately.The calibration curves were plotted,which showed the relationship between spectral line intensity values and chromium concentrations in different samples.And then their respective linear correlations were compared.The experimental results showed that the linear correlation of the intensity values of spectral feature lines and the concentrations of chromium in different samples,which was obtained by damped least squares method,was better than that one obtained by least squares method.And therefore,damped least squares method was stable,reliable and suitable for separating,fitting and extracting spectral feature lines in laser induced breakdown spectroscopy.
