Vývoj spektrometrie laserem buzeného plazmatu s dálkovou detekcí pro analýzu předmětů archeologických objektů

Development of a Remote Laser-Induced Breakdown Spectroscopy Setup for Analysis of Archaeological Objects

abstrakt

en

LIBS has emerged as a very promising technique for the analysis and characterization of a broad variety of objects of cultural heritage including pottery, sculpture, metal and stone objects. One of the numerous modifications of LIBS is the so-called remote LIBS (rLIBS), which is applicable to stand-off analyses of solid, liquid, and gas samples. Using our rLIBS setup under development, we proved that remote LIBS has the analytical potential for analyses of calcified organic tissues in the open air over a range of several meters. The sensitivity on selected P, Mg, Na, Zn, and Sr emission lines is sufficient for quantification of these elements. The results show that the measured quantities of minor elements by Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS) and remote LIBS are comparable at a semiquantitative level. It was concluded that the designed rLIBS setup with a relatively large collecting mirror is capable of analysis at the level of units of mg kg-1. It was also shown that the combination of artificial neural networks (ANN) and rLIBS spectrometry can become a powerful tool for the identification of biominerals or brick samples. The combination of ANN + rLIBS can be used for fast semiquantitative analysis of different brick samples; the chemical, physical and mechanical properties of bricks can be monitored. Using rLIBS the different type, origin and degree and cause of the damage on the studied masonry may be classified. This can help e.g. in the selection of compatible materials for the replacement of original bricks that is crucial in order to avoid damage to the historical structure. Here we present the recent development of the rLIBS setup primarily constructed for analysis of archaeological objects. We will focus on the characterization of brick samples using the advanced version of this setup. The outcomes will be compared with the results obtained on the same samples in the laboratory of our Chinese partner.

Metoda LIBS se ukázala jako velice slibná pro analýzu a charakterizaci široké škály objektů kulturního dědictví jako jsou kovové a kamenné objekty, sochy, keramika a pod. Jedna z řady modifikací LIBS, tzv. remote LIBS (rLIBS) umožňuje dálkovou analýzu pevných, kapalných i plynných vzorků. S použitím námi vyvinutého dálkového LIBS systému byla ověřena možnost analýzy kalcifikovaných organických tkání na vzdálenost několika metrů. Citlivost byla dostatečná pro pro řadu prvků jako P,Mg, Na, Zn a Sr. Pro semikvantitativní analýzu těchto prvků je metoda dostatečně spolehlivá, což bylo ověřeno na základě porovnání s výsledky obdrženými pomocí metody laserové ablace ve spojení s hmotnostní spektrometrií indukčně vázaného plazmatu (LA-ICP-MS).

LIBS has emerged as a very promising technique for the analysis and characterization of a broad variety of objects of cultural heritage including pottery, sculpture, metal and stone objects. One of the numerous modifications of LIBS is the so-called remote LIBS (rLIBS), which is applicable to stand-off analyses of solid, liquid, and gas samples. Using our rLIBS setup under development, we proved that remote LIBS has the analytical potential for analyses of calcified organic tissues in the open air over a range of several meters. The sensitivity on selected P, Mg, Na, Zn, and Sr emission lines is sufficient for quantification of these elements. The results show that the measured quantities of minor elements by Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS) and remote LIBS are comparable at a semiquantitative level. It was concluded that the designed rLIBS setup with a relatively large collecting mirror is capable of analysis at the level of units of mg kg-1. It was also shown that the combination of artificial neural networks (ANN) and rLIBS spectrometry can become a powerful tool for the identification of biominerals or brick samples. The combination of ANN + rLIBS can be used for fast semiquantitative analysis of different brick samples; the chemical, physical and mechanical properties of bricks can be monitored. Using rLIBS the different type, origin and degree and cause of the damage on the studied masonry may be classified. This can help e.g. in the selection of compatible materials for the replacement of original bricks that is crucial in order to avoid damage to the historical structure. Here we present the recent development of the rLIBS setup primarily constructed for analysis of archaeological objects. We will focus on the characterization of brick samples using the advanced version of this setup. The outcomes will be compared with the results obtained on the same samples in the laboratory of our Chinese partner.

Remote detection; laser induced breakdown spectroscopy; LIBS

18.07.2011

100–101

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