Determination of isotope abundance and elemental concentration of lithium by thermal ionization mass spechometry
Description
An analytical method for the determination of the isotope abundance and elemental concentration of lithium by mass spectrometry has been developed. A study, envolving the optimization of the various experimental parameters aimed at reducing the isotope fractionation that occur during evaporation, has been made. The experimental parameters optimized are: type of filament arrangement, accelerating voltage of the ions, quantity and chemical form of the samples deposited and the temperature of ionization. The effect of isotope fractionation on the isotope ratio measurements has been studied and compared with the theoretical model of Kanno and correction has been applied based on the variation of the isotope ratio of lithium with the time of analysis. The concentration of lithium in a sample of uranyl nitrate and an U.S.G.S. rock standard has been determined by the mass spectrometric isotope dilution technique using a tracer enriched in lithium-6. (Author)
Availability note (English)
Available from IPEN, Brazil.Abstract (Portuguese)
Desenvolveu-se, neste trabalho, um metodo analitico de determinacao da composicao isotopica e de baixas concentracao de litio por espectrometria de massa. Um estudo foi realizado para a otimizacao dos parametros experimentais ligados ao espectrometro de massa, com o objetivo de minimizar o efeito de fracionamento isotopico, que afeta a precisao e exatidao das medidas da razao isotopica de litio. Os parametros experimentais otimizados, para determinar a razao isotopica de litio, foram: tipo de arranjo de filamento, aceleracao de voltagem de ions, quantidade e forma quimica de amostra depositada no filamento e temperatura de ionizacao. O efeito de fracionamento isotopico foi estudado, comparado com o modelo teorico de Kanno e corrigido, atraves da variacao da medida da razao isotopica do litio em funcao do tempo de analise. Determinou-se a concentracao e litio numa amostra de nitrato de uranila e numa amostra de rocha padrao da United States Geological Survey, pela tecnica de diluicao isotopica-espectrometria de massa, utilizando um tracador enriquecido no isotopo de litio-6. (Autor)Additional details
Additional titles
- Original title (Portuguese)
- Determinacao da abundancia isotopica e concentracao de litio por espectrometria de massa termoionica
Publishing Information
- Imprint Pagination
- 78 p.
INIS
- Country of Publication
- Brazil
- Country of Input or Organization
- Brazil
- INIS RN
- 16023570
- Subject category
- S37: INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY;
- Resource subtype / Literary indicator
- Thesis, Non-conventional Literature
- Descriptors DEI
- ISOTOPE RATIO; LITHIUM 6; MASS SPECTROSCOPY; URANYL NITRATES
- Descriptors DEC
- ACTINIDE COMPOUNDS; ISOTOPES; LIGHT NUCLEI; LITHIUM ISOTOPES; NITRATES; NITROGEN COMPOUNDS; NUCLEI; ODD-ODD NUCLEI; OXYGEN COMPOUNDS; SPECTROSCOPY; STABLE ISOTOPES; URANIUM COMPOUNDS; URANYL COMPOUNDS