本文選題：激光誘導(dǎo)擊穿光譜　切入點(diǎn)：定量分析　出處：《長(zhǎng)江大學(xué)》2015年碩士論文

【摘要】：激光誘導(dǎo)擊穿光譜技術(shù)(laser induced breakdown spectroscopy, LIBS)是激光應(yīng)用領(lǐng)域中的一種分析技術(shù)。LIBS使用脈沖激光蒸發(fā)少量的樣本生成等離子體,處于激發(fā)態(tài)的物質(zhì)(如原子、離子)發(fā)射出的光譜信息用于元素的定性與定量分析。原油及輸油管道污垢中微量元素會(huì)腐蝕反應(yīng)器和輸油管道,造成嚴(yán)重的后果。本文以LIBS的技術(shù)原理及實(shí)際應(yīng)用為基礎(chǔ),針對(duì)灰化后的原油樣品及輸油管道污垢中的元素開(kāi)展了以下研究。根據(jù)原油和輸油管道污垢中微量元素的危害及LIBS分析技術(shù)的特點(diǎn)來(lái)說(shuō)明課題的來(lái)源及研究意義,簡(jiǎn)述LIBS技術(shù)的發(fā)展歷程、優(yōu)缺點(diǎn)及工作原理。從應(yīng)用領(lǐng)域,檢測(cè)能力及設(shè)備開(kāi)發(fā)三個(gè)方面介紹LIBS技術(shù)在國(guó)內(nèi)外應(yīng)用方面的研究現(xiàn)狀。對(duì)課題研究時(shí)使用的儀器——-RT100-HP LIBS及其功能進(jìn)行簡(jiǎn)介。提出“散點(diǎn)圖”分析和處理異常數(shù)據(jù)的方法,并對(duì)處理的效果進(jìn)行分析說(shuō)明。引入相關(guān)系數(shù)R作為檢驗(yàn)回歸分析結(jié)果是否有意義的判斷依據(jù),再通過(guò)實(shí)驗(yàn)數(shù)據(jù)分析討論激光脈沖能量、照射光斑大小及探測(cè)延遲時(shí)間等儀器參數(shù)對(duì)光譜強(qiáng)度的影響。分析結(jié)果表明,在一定激光脈沖能量強(qiáng)度范圍內(nèi),光譜強(qiáng)度與激光脈沖能量成正比；激光脈沖能量等其它條件不變時(shí),隨著激光照射光斑直徑的增加,光譜強(qiáng)度逐漸減小；當(dāng)延遲時(shí)間大于1微秒時(shí),光譜強(qiáng)度隨延遲時(shí)間的增加而逐漸降低。詳細(xì)介紹LIBS的兩個(gè)應(yīng)用實(shí)例.在LIBS分析灰化后的原油一例中,以Na I588.995nm為主要分析對(duì)象。首先簡(jiǎn)單概述光譜背景的由來(lái)及處理方法。再利用降噪后的積分強(qiáng)度、峰值強(qiáng)度作定標(biāo)曲線對(duì)Na進(jìn)行定量分析；實(shí)驗(yàn)中選取Na I588.995nm、Mg Ⅰ 285.213nm、Al Ⅱ 308.215 nm、K Ⅰ 404.414nm、Ca Ⅰ 396.847nm、FeⅡ273.955nm作為分析線對(duì)原油樣品灼燒后的6種元素進(jìn)行分析,測(cè)得其含量分別為5.92%、0.32%、2.12%、0.19%、0.68%、16.86%,并得出了定標(biāo)曲線的線性相關(guān)系數(shù)及檢出限。結(jié)果表明,選用積分強(qiáng)度作定標(biāo)曲線效果更好；激光誘導(dǎo)擊穿光譜技術(shù)測(cè)量結(jié)果與X射線熒光光譜技術(shù)對(duì)Na的測(cè)量結(jié)果相對(duì)誤差為6.28%；激光誘導(dǎo)擊穿光譜技術(shù)可應(yīng)用于對(duì)灰化后原油金屬元素進(jìn)行定量分析。在LIBS分析輸油管道污垢一例中,以Mg為研究重點(diǎn),首先將譜線Mg I285.213nm降噪前、后的積分強(qiáng)度、峰值強(qiáng)度作定標(biāo)曲線的測(cè)量結(jié)果進(jìn)行分析對(duì)比。再講解重疊光譜的兩種分解方法—高斯線型擬合分峰和洛倫茲線型擬合分峰。最后對(duì)比Mg Ⅱ 279.553nm、Mg Ⅱ 280.270nm和Mg Ⅰ 285.213nm三條譜線作定標(biāo)曲線的分析效果。結(jié)果表明洛倫茲線型更適合對(duì)重疊光譜進(jìn)行擬合分峰,采用相對(duì)強(qiáng)度大且降噪后的譜線的積分強(qiáng)度作定標(biāo)曲線更適合對(duì)元素進(jìn)行定量分析。在文章的最后對(duì)全文做了總結(jié),并對(duì)后期的工作做了幾點(diǎn)計(jì)劃。
[Abstract]:Laser induced breakdown spectroscopy (Libs) is an analytical technique in the field of laser applications. Libs uses pulsed laser to vaporize a small amount of samples to form plasma, which is in an excited state, such as atoms.The emitted spectral information is used for qualitative and quantitative analysis of elements.Trace elements in crude oil and oil pipeline dirt will corrode reactors and pipelines, causing serious consequences.Based on the technical principle and practical application of LIBS, the following researches have been carried out on the ashes of crude oil samples and the elements in oil pipeline fouling.According to the harm of trace elements in the dirt of crude oil and oil pipeline and the characteristics of LIBS analysis technology, this paper explains the source of the subject and its research significance, and briefly describes the development course, advantages and disadvantages and working principle of LIBS technology.This paper introduces the application of LIBS technology in China and abroad from three aspects: application field, detection ability and equipment development.This paper introduces the instrument used in the research-RT100-HP LIBS and its functions.This paper puts forward the method of analyzing and dealing with abnormal data by "scatter plot", and analyzes and explains the effect of processing.The correlation coefficient R is introduced as the basis for judging whether the regression analysis results are meaningful or not. The influence of the parameters of laser pulse energy, spot size and detection delay time on the spectral intensity is discussed through the analysis of experimental data.The results show that the spectral intensity is proportional to the laser pulse energy in a certain range of laser pulse energy, and the spectral intensity decreases gradually with the increase of laser spot diameter when other conditions such as laser pulse energy are not changed.When the delay time is more than 1 microsecond, the spectral intensity decreases with the increase of delay time.Two application examples of LIBS are introduced in detail.In the case of LIBS analysis of crude oil after ashing, Na I588.995nm was used as the main analysis object.Firstly, the origin and processing method of spectral background are briefly summarized.The calculated integral intensity and peak intensity were used as calibration curves for quantitative analysis of Na, and mg 鈪，

本文編號(hào)：1724890