【摘要】：激光誘導擊穿光譜(Laser-Induced Breakdown Spectroscopy,LIBS)技術作為一種成分分析技術已不斷被廣泛利用,利用該技術測試土壤中金屬含量在環(huán)境檢測、農(nóng)業(yè)發(fā)展方向都有重大意義。LIBS技術利用高能脈沖激光產(chǎn)生的等離子體燒蝕并激發(fā)樣品(通常為固體)中的物質(zhì),并通過高分辨率的光譜儀獲取等離子體激發(fā)的原子或分子所發(fā)射的光譜,以此來識別樣品中的元素組成和含量。LIBS可以分析任何狀態(tài)的物質(zhì),可以進行材料的識別、分類、定性以及定量分析。LIBS的分析依賴于脈沖激光器的能量和光譜儀、探測器的靈敏度和波長范圍,它的檢測限是脈沖激光器產(chǎn)生的等離子體溫度、收集窗口和元素的躍遷譜線強度的函數(shù)。本論文在分析了傳統(tǒng)的土壤重金屬檢測技術基礎上,提出了LIBS重金屬Pb和Mn快速檢測方法。對激光誘導等離子體理論進行了研究,主要研究了激光誘導等離子體光譜及其特性,包括等離子體發(fā)射光譜分析基本原理,LIBS實驗裝置及性能參數(shù)。研究分析了LIBS的定量分析方法,包括外標法、內(nèi)標法、免標法、多元素定標分析方法,以及PCA、PLS、ANN等多變量分析方法。論文還搭建了LIBS土壤重金屬快速測定實驗平臺,并對實驗參數(shù)進行了分析和初步優(yōu)化。通過檢測不同濃度的土壤重金屬Pb和Mn,獲得了土壤中Pb和Mn的LIBS光譜,并分析了Pb和Mn元素的分析譜線Pb(Ι)405.78nm和Mn(Ⅱ)257.61nm的可行性。論文在建立定標曲線的基礎上定量分析了Pb和Mn的含量。實驗表明激光誘導擊穿光譜技術能夠快速檢測土壤重金屬Pb和Mn,對于土壤中重金屬元素的快速分析具有重大意義,為土壤重金屬污染和土壤元素的快速檢測提供了新的思路途徑。
[Abstract]:Laser induced breakdown spectroscopy (Laser-Induced Breakdown Spectroscopy,LIBS) has been widely used as a component analysis technique. The development of agriculture is of great significance. LIBS technology uses plasma generated by high-energy pulsed lasers to ablate and excite substances in samples (usually solids). The spectra of atoms or molecules excited by plasma are obtained by high-resolution spectrometer to identify the composition and content of elements in the sample. LIBS can be used to analyze substances in any state and to identify and classify materials. Qualitative and quantitative analysis. The analysis of LIBS depends on the energy and spectrometer of the pulsed laser, the sensitivity and wavelength range of the detector, and its detection limit is the plasma temperature produced by the pulsed laser. A collection of window and element transition line strength functions. In this paper, based on the analysis of traditional soil heavy metal detection techniques, a rapid detection method of LIBS heavy metal Pb and Mn was proposed. The theory of laser-induced plasma is studied in this paper. The laser induced plasma spectrum and its characteristics are mainly studied, including the basic principle of plasma emission spectrum analysis, LIBS experimental device and performance parameters. The quantitative analysis methods of LIBS, including external standard method, internal standard method, non-standard method, multielement calibration analysis method and PCA,PLS,ANN multivariate analysis method, are studied and analyzed. The experimental platform for rapid determination of heavy metals in LIBS soil was also set up, and the experimental parameters were analyzed and preliminarily optimized. The LIBS spectra of Pb and Mn in soils with different concentrations of heavy metal Pb and Mn, were obtained, and the feasibility of Pb (I) 405.78nm and Mn (鈪，

本文編號：2309343