IAP 12IAP 12--091 Session 1, January 03,091 Session 1, January 03, 2005200511Trace Element AnalysisTrace Element Analysis of Geological, Biological &of Geological, Biological & Environmental MaterialsEnvironmental Materials By Neutron Activation Analysis:By Neutron Activation Analysis:An ExposureAn ExposureILA PILLALAMARRIILA PILLALAMARRIEarth Atmospheric & Planetary SciencesEarth Atmospheric & Planetary SciencesNeutron Activation Analysis LaboratoryNeutron Activation Analysis LaboratoryMassachusetts Institute of TechnologyMassachusetts Institute of Technology Cambridge, MA 02139Cambridge, MA 02139IAP 12.091 Credit Course January 3IAP 12.091 Credit Course January 3 --19, 200519, 2005IAP 12.091 SESSION 1 1SESSION 1 January 03, 2005 Introduction Neutron Activation Analysis Principles IAP 12-091 Session 1, January 03, 2005 2 IAP 12.091 SESSION 1 2INTRODUCTION The key words in the title of the course are: Biological, Environmental and Geological Materials Trace Element Analysis Neutron Activation Analysis Exposure IAP 12-091 Session 1, January 03, 2005 3 IAP 12.091 SESSION 1 3INTRODUCTION … Materials and Matrices What is the need to do Trace Element Analysis? What are the Trace Element Analytical Techniques ? IAP 12-091 Session 1, January 03, 2005 4 IAP 12.091 SESSION 1 4Materials and Matrices Biological Materials Environmental Materials Geological Materials IAP 12-091 Session 1, January 03, 2005 5 IAP 12.091 SESSION 1 5Materials and Matrices … Biological Materials Hair samples, Nails, Blood samples … Environmental Materials River, Lake, Beach sediments, Atmospheric Dust … Geological Materials Ocean floor cores, Volcanic lava rocks, Mountain Rocks, Lunar rocks, Mars soils… IAP 12-091 Session 1, January 03, 2005 6 IAP 12.091 SESSION 1 6Materials and Matrices … Matrix of a material Major Elements Minor Elements Trace Elements IAP 12-091 Session 1, January 03, 2005 7 IAP 12.091 SESSION 1 7Major, Minor & Trace Element Composition of Materials Conventionally: Major: Concentrations exceeding 1% by mass Minor: Concentrations in the range 0.1% to 1.0% by mass Trace : Concentrations less than 0.1% by mass Different trace levels ppm mg/g (micro gram/gram) 10-6 gm/gm ppb ng/g (nano gram/gram) 10-9 gm/gm ppt pg/g (pico gram/gram) 10-12 gm/gm ppf fg/g (femto gram/gram) 10-15 gm/gm ppa ag/g (atto gram/ gram) 10-18 gm/gm IAP 12-091 Session 1, January 03, 2005 8 Reference: Chapter 1: What a geochemical analysis means , p 1-3 by Robin Gill and Michael H Ramsey Modern Analytical Geochemistry An introduction to Quantitative Chemical Analysis Techniques for Earth, Environmental and Material Scientists. Ed: Robin Gill Addison Wesley Longman Ltd. 1997 IAP 12.091 SESSION 1 8What is the need to do Trace Element Analysis? Need for Environmental: Pollution studies, Monitoring statutory values … Biological: Nutrition studies, forensic analyses Geological: Trace element geochemistry of terrestrial and extra terrestrial matters ………… ………… IAP 12-091 Session 1, January 03, 2005 9 IAP 12.091 SESSION 1 9Trace Element Analysis – Needs Analysis means to determine the composition of a material. In the context of trace element analysis by neutron activation analysis – measurement of concentration (abundance) of certain elements in the material, orrelative amounts of two or more isotopes in a material. Trace element analyses are carried out on terrestrial andextra-terrestrial materials. Terrestrial materials – air, volcanic lavas, rocks, gas, water, atmospheric dust, soil or rock, or processedmaterials like sewage sludge or industrial effluent Extra-terrestrial materials – lunar rocks, martian soils,meteorites …. IAP 12-091 Session 1, January 03, 2005 10 Reference: Chapter 1: What a geochemical analysis means , p 1-3 by Robin Gill and Michael H Ramsey Modern Analytical Geochemistry An introduction to Quantitative Chemical Analysis Techniques for Earth, Environmental and Material Scientists. Ed: Robin Gill Addison Wesley Longman Ltd. 1997 IAP 12.091 SESSION 1 10Trace Element Analysis – Needs … Needs (or applications): Compositional characterization of a completelyunknown material. Quality control/Quality assurance of manufactured products monitroing/testing statutory or recommended limits in contaminated materials Geothermobarometric details of a sample’s composition to understand anthropogenic history IAP 12-091 Session 1, January 03, 2005 11 IAP 12.091 SESSION 1 11Trace Element Analysis – Needs … Temporal details of materials for archaeological and forensic applications Temporal compositional variation – industrial spills, power plant accident … Compositional spatial distribution mapping of elements to identify sources – of river pollution, location of exposed ore deposits in stream sediments, wells Efficiency monitoring to optimize the conditions of experiments or industrial processes. IAP 12-091 Session 1, January 03, 2005 12 Reference: Chapter 1: What a geochemical analysis means , p 1-3 by Robin Gill and Michael H Ramsey Modern Analytical Geochemistry An introduction to Quantitative Chemical Analysis Techniques for Earth, Environmental and Material Scientists. Ed: Robin Gill Addison Wesley Longman Ltd. 1997 IAP 12.091 SESSION 1 12Different types of Analyses - Concepts Qualitative & Quantitative analysis Major, Minor & Trace element analysis Bulk & Spatial analysis Isotopic composition analysis Speciation & Spectroscopic analysis (Cannot be done by Neutron Activation Analysis) IAP 12-091 Session 1, January 03, 2005 13 Reference: Chapter 1: What a geochemical analysis means , p 1-3 by Robin Gill and Michael H Ramsey Modern Analytical Geochemistry An introduction to Quantitative Chemical Analysis Techniques for Earth, Environmental and Material Scientists. Ed: Robin Gill Addison Wesley Longman Ltd. 1997 IAP 12.091 SESSION 1 13Different types of Analyses – Concepts … Qualitative & Quantitative analysis Qualitative means identification of an element at detectable level – preliminary investigations Quantitative means measurement of the values of concentrations Major, Minor & Trace element analysis Major: Concentrations exceeding 1% by mass Minor: Concentrations in the range 0.1% to 1.0% by mass Trace :Concentrations less than 0.1% by mass ppm mg/g (micro gram/gram) 10-6 gm/gm
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