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Instrumental neutron activation analysis (INAA) is a non-destructive,
highly precise and accurate analytical technique capable of determining
up to 48 elements in almost all types of sample matrices. The
INAA procedure involves irradiating the samples and appropriate
standard reference materials with neutrons in the USGS TRIGA
reactor to produce unstable radioactive nuclides. Many of these
radionuclides emit gamma-rays with characteristic energies that
can be measured utilizing high-resolution semiconductor detectors.
The rate that the gamma-rays are emitted from an element in the
sample is directly proportional to its concentration. Samples
as small as 1mg can be quantitatively measured by INAA. Detection
limits are in the parts per million to parts per billion range
depending on the element and sample matrix.
- Al, Au, Ag, As, Ba, Br, Ca, Cd, Co, Cr, Cs, Cu, Fe, Hf, Hg,
Ir, K, Mg, Mo, Na,
- Ni, Rb, S, Sb, Sc, Se, Sn, Sr, Ta, Th, Ti, U, V, W, Zn, Zr,
La, Ce, Nd, Sm, Eu, Gd, Tb, Dy,
- Ho, Tm, Yb, Lu
- Rocks , Minerals, Soils, Sand, Gravel
- Meteorites
- Coal, Fly ash
- Fossils
- Water
- Carbonates, evaporites
- Breccias
- Humus
- Plastic
- Chemicals
- Colloids
- Metals, alloys
- Rubber
- Paper
- Insects
- Paint
- Varnish
- Dust and air-borne particles collected on filters
- Animal parts (shells, hair, organs, skin, teeth, bones, nails,
etc.)
- Bird parts (feathers, bills, claws, etc.)
- Fish parts (livers, muscles, fins, etc.)
- Vegetation (wheat, corn, bark, leaves, grasses, needles)
- Fertilizer
- Pesticides
- Coral
- Fuels (gas and oil)
- Lubricating oils (engines and machinery)
- Building materials (concrete, asphalt, cement, wood, steel,
glass)
- Forensic samples (blood, bullets, fibers, hair, cloth)
- Any (water, fuel and oil samples are evaporated to dryness)
- Varies, typically 1-5%
- Elemental characterization and correlation of deposits or
formations (geologic studies)
- Environmental monitoring (atmospheric, soil and water pollution
studies)
- Corrosion and frictional effects (industrial studies)
- Nutrient deficiencies (agricultural and medical studies)
- Contamination (chemical studies)
- Sample identification and correlation (forensic studies)
- Ge-Well detector for analyzing small (1 mg) samples. Pneumatic
transfer facility for rapid transport of samples following irradiation.
- $50-$100 depending on the precision of analysis required.
- All detectors except Ge-Well are equipped with automatic
sample changers.
- About 100mg is preferred, but samples as small as 1mg are
acceptable.
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