Abstract
Methodology for determining trace thorium levels in a variety of sample types was further developed. Thorium in filtered water samples is concentrated by ferric hydroxide precipitation followed by dissolution and co-precipitation with lanthanum fluoride. Aerosols on glass fibre, cellulose ester, or teflon filters and solid soil and sediment samples are acid digested. Subsequently thorium is concentrated by lanthanum fluoride co-precipitation. Chemical separation and measurement is then done on a Technicon AA11-C autoanalyzer, using solvent extraction into thenoyltrifuoroacetone in kerosene followed by back extraction into 2 N{sub H}NO{sub 3}, and colourometric measurement of the thorium arsenazo III complex. Chemical yields are determined by the addition of thorium-234 tracer using gamma-ray spectrometry. The sensitivities of the methods for water, aerosol and solid samples are approximately 1.0 {mu}g/L, 0.5 {mu}g/g and 1.0 {mu}g/g respectively. At thorium levels about ten times the detection limit, accuracy is estimated to be {+-} 10% for liquids and aerosols and {+-} 15% for solid samples, and precision {+-} 5% for all samples.
Citation Formats
Stuart, J E, and Robertson, R.
Development of an automated method for determination of thorium in soil samples and aerosols.
Canada: N. p.,
1986.
Web.
Stuart, J E, & Robertson, R.
Development of an automated method for determination of thorium in soil samples and aerosols.
Canada.
Stuart, J E, and Robertson, R.
1986.
"Development of an automated method for determination of thorium in soil samples and aerosols."
Canada.
@misc{etde_10140424,
title = {Development of an automated method for determination of thorium in soil samples and aerosols}
author = {Stuart, J E, and Robertson, R}
abstractNote = {Methodology for determining trace thorium levels in a variety of sample types was further developed. Thorium in filtered water samples is concentrated by ferric hydroxide precipitation followed by dissolution and co-precipitation with lanthanum fluoride. Aerosols on glass fibre, cellulose ester, or teflon filters and solid soil and sediment samples are acid digested. Subsequently thorium is concentrated by lanthanum fluoride co-precipitation. Chemical separation and measurement is then done on a Technicon AA11-C autoanalyzer, using solvent extraction into thenoyltrifuoroacetone in kerosene followed by back extraction into 2 N{sub H}NO{sub 3}, and colourometric measurement of the thorium arsenazo III complex. Chemical yields are determined by the addition of thorium-234 tracer using gamma-ray spectrometry. The sensitivities of the methods for water, aerosol and solid samples are approximately 1.0 {mu}g/L, 0.5 {mu}g/g and 1.0 {mu}g/g respectively. At thorium levels about ten times the detection limit, accuracy is estimated to be {+-} 10% for liquids and aerosols and {+-} 15% for solid samples, and precision {+-} 5% for all samples.}
place = {Canada}
year = {1986}
month = {Sep}
}
title = {Development of an automated method for determination of thorium in soil samples and aerosols}
author = {Stuart, J E, and Robertson, R}
abstractNote = {Methodology for determining trace thorium levels in a variety of sample types was further developed. Thorium in filtered water samples is concentrated by ferric hydroxide precipitation followed by dissolution and co-precipitation with lanthanum fluoride. Aerosols on glass fibre, cellulose ester, or teflon filters and solid soil and sediment samples are acid digested. Subsequently thorium is concentrated by lanthanum fluoride co-precipitation. Chemical separation and measurement is then done on a Technicon AA11-C autoanalyzer, using solvent extraction into thenoyltrifuoroacetone in kerosene followed by back extraction into 2 N{sub H}NO{sub 3}, and colourometric measurement of the thorium arsenazo III complex. Chemical yields are determined by the addition of thorium-234 tracer using gamma-ray spectrometry. The sensitivities of the methods for water, aerosol and solid samples are approximately 1.0 {mu}g/L, 0.5 {mu}g/g and 1.0 {mu}g/g respectively. At thorium levels about ten times the detection limit, accuracy is estimated to be {+-} 10% for liquids and aerosols and {+-} 15% for solid samples, and precision {+-} 5% for all samples.}
place = {Canada}
year = {1986}
month = {Sep}
}