Construction and evaluation of a laser induced breakdown spectroscopy instrument: application in alloy samples / Construção e avaliação de um instrumento para espectroscopia de emissão em plasma induzido por laser (LIBS) : aplicação em ligas metalicas
AUTOR(ES)
Juliana Cortez
DATA DE PUBLICAÇÃO
2007
RESUMO
In this work a time resolved LIBS instrument (TRELIBS) was built and its performance evaluated in qualitative and quantitative analysis. Additionally, exploratory studies are presented on the influence of parameters that affect the LIBS analysis. The instrument was built employing optical systems and devices of modern technology: an ICCD device, an echelle polychromator and an Q-switched Nd:YAG laser. Three configurations of LIBS system were evaluated. In the last configuration, the laser pulse was reflected by a dicroic mirror at 45º to a lens of 25 cm focal distance that focused the laser pulse on the sample surface. The plasma emission was collected by a lens of short focal distance and sent to the echelle, through of an optical fiber, and later to the ICCD. In qualitative analysis, spectra of copper and zinc foils were evaluated and the spectral lines were found in agreement with literature, considering the echelle resolution. In quantitative analysis, manganese was determined in killed steel. The system presented signals at 293,30 nm whose intensities changes in function of manganese concentration and analytical curves were obtained. The laser pulse energy showed to be an important factor for the success of quantitative analysis. Others parameters such as width, delay time, MCP gain, accumulated laser pulses and distance sample-focusing lens also showed have influence in quantitative analysis. MEV images and surface scanner by EDS of the craters formed by laser were important tools to understanding laser-sample-atmosphere interaction processes
ASSUNTO(S)
determinação de manganes killed steel libs manganese determination
ACESSO AO ARTIGO
http://libdigi.unicamp.br/document/?code=vtls000413457Documentos Relacionados
- Estudo de uma metodologia para estimar a quantidade de carbono em amostras de solo utilizando espectroscopia de emissão óptica com plasma induzido por laser (LIBS)
- Aplicação da espectroscopia de emissão ótica com plasma induzido por laser (LIBS) na quantificação de carbono em amostras de solo intacto.
- LASER INDUCED-BREAKDOWN SPECTROSCOPY (LIBS): HISTÓRICO, FUNDAMENTOS, APLICAÇÕES E POTENCIALIDADES
- Combination of Multi-Energy Calibration (MEC) and Laser-Induced Breakdown Spectroscopy (LIBS) for Dietary Supplements Analysis and Determination of Ca, Mg and K
- Estratégias quimiométricas para análise de plantas por espectrometria de emissão óptica com plasma induzido por laser