Neutron activation analyses trace element studies

Salmon, L., Instrumental Neutron Activation Analysis in Environmental Studies of Trace Elements, AERE-R 7859, HMSO, 1975. 

Ehmann, W.D., Maerkesbery, W.R., Kasarskis, E.J., Vance, D.E., Khare, S.S., Hord, J.D. and Thompson, C.M. (1987) Applications of neutron activation analysis to the study of age-related neurological diseases. Biol. Trace Element Res., 13,19-33. 

Iieser et al. [628] studied the application of neutron activation analysis to the determination of trace elements in seawater. The rare earths included in this study were cerium and europium. The element concerned were adsorbed onto charcoal. Between 75% and 100% of the elements were adsorbed onto the charcoal which was then subjected to analysis by neutron activation analysis. Cerium (300 p,g/l) and europium (0.00082 pg/1) were found in North Sea water by this method. 

Study of chemical pathways in method development. Isotope dilution methods. Radioimmunoassay very important in biochemistry and medicine. Neutron activation analysis used for trace elements in geo-chemistry, semiconductor technology, pollution studies and forensic science. Relative precision of counting 1% if 104 counts are recorded. Assessment of pollution by radionuclides. 

Neutron activation analysis is an attractive method in many trace element problems, or where the total amount of sample is limited. Many geochemical studies of trace constituents and semi-conductor developments have used the technique, whilst in recent years pollution investigations have provided a new focus. In forensic science small flakes of paint, single hairs and a variety of other small samples have been analysed and identified by activation analysis. In recent years activation analysis has lost further ground to ICP-MS which provides more comprehensive information and is more readily operated. Sensitivity is also comparable in many cases. 

Studies of the inorganics in cotton dust have incorporated the use of a wide variety of techniques. These include X-ray fluorescence spectroscopy, atomic absorption spectroscopy, electron microscopy, energy dispersive analysis of X-rays, X-ray diffraction, atomic absorption spectroscopy, neutron activation analysis and petrographic microscopy. It is necessary to use a wide array of techniques since no single technique will permit the measurement of all trace elements. Steindard chemical techniques to determine the ash content of samples and of various extracts have also been used. In most of these studies the ash fraction has been considered to be a reasonably accurate measure of the inorganic content. 

Cluster analysis Is used to determine the particle types that occur in an aerosol. These types are used to classify the particles in samples collected from various locations and sampling periods. The results of the sample classifications, together with meteorological data and bulk analytical data from methods such as instrunental neutron activation analysis (INAA). are used to study emission patterns and to screen samples for further study. The classification results are used in factor analysis to characterize spatial and temporal structure and to aid in source attribution. The classification results are also used in mass balance comparisons between ASEM and bulk chemical analyses. Such comparisons allow the combined use of the detailed characterizations of the individual-particle analyses and the trace-element capability of bulk analytical methods. 

In most obsidian provenance studies, the ability to employ compositional differences to discriminate between sources depends, to a certain extent, on the number of elements measured. Because instrumental neutron activation analysis (INAA) is capable of measuring 25-30 elements in obsidian with excellent precision, numerous combinations of trace and major elements are available for comparing differences between sources. The main requirements for success are that all sources have been located and analyzed, and that the internal variation measured within the sources be smaller than the compositional differences measured between the sources (23). 

Trace element studies of ceramics have been undertaken for the purpose of locating source regions for archaeological materials since the 1960s. While a number of techniques have been used for this purpose, by far the most common and most effective has been instrumental neutron activation analysis (INAA), largely due to its excellent sensitivity, precision, accuracy and the large number of elements it can measure simultaneously. 

Tomza U, Janicki T, Kossman S. 1983. Instrumental neutron activation analysis of trace elements in hair A study of occupational exposure to a non-ferrous smelter. Radiochem and Radioanal Letters 58 209-220. 

Species distribution studies have shown that trace element (e.g. metals) concentrations in soils and sediments vary with physical location (e.g. depth below bed surface) and with particle size. In these speciation studies the total element content of each fraction was determined using a suitable trace element procedure, for example, solid sample analysis by X-ray emission spectroscopy or neutron activation analysis, or alternatively by dissolution of sample and analysis by ICPOES, AAS or ASV. The type of sample fraction analysed can vary, and a few... 

In many laboratories that have access to a nuclear reactor, neutron activation is used for the chemical analysis of rocks, minerals, petroleum, biological tissues, alloys, etc., and the technique is well suited for the determination of the concentrations of trace elements in polymers. Neutron activation analysis was used by Given et al. (1) in their studies of water tree growth in polymeric insulation and by Wu and Chen (2) in their studies of dopant-polymer interactions in MoCl5-dcped polyacetylene films. In this work the principles of the method are described and the possibilities are illustrated by means of measurements carried out on polyethylene. 

Many trace element studies of archaeological samples have used neutron activation analysis (NAA). Although this technique is not useful for all elements, it is very sensitive for many of those that have proved to be valuable indicators of geochemical processes (e.g., the rare earth elements). The precision of the actual measurements is usually high and easy to determine. Samples can be irradiated with little or no sample preparation, so there are few chances of contamination during the analysis. However, the limited number of nuclear reactors severely limits access to this type of analysis. When samples are sent to a distant laboratory for analysis, the critical interaction between archaeologist and analyst can be lost. 

To show that REE and other trace elements could be used to characterize soapstone formations, it was necessary to show that variations between geologic bodies were greater than those for soapstone samples found within the formation. For these studies instrumental neutron activation analysis (INAA) was used because of its sensitivity and preci-... 

Neutron Activation. In environmental and industrial process studies, neutron activation analysis (NAA) currently is being used widely because of its inherently high sensitivity and accuracy. In complex substances such as are found in solvent-refined coal and oil shale retorting processes, NAA is the method of choice for many trace element analyses because of its relative freedom from matrix effects. 

These techniques are normally adequate to answer most of the questions encountered on archaeological sites however, complex stratigraphy and unusual soil conditions can present a more difficult problem. In this chapter, we explore what additional information might be provided by a more comprehensive elemental analysis. Instrumental neutron activation analysis (INAA) was chosen because it provides concentration data for both the major elements usually obtained by conventional techniques and the trace elements used in many provenance studies. 

Plantin LO, Lying-Tunell U, Kristensson K. 1987. Trace elements in the human central nervous system studied with neutron activation analysis. Biol Trace Elem Res 13 69-75. 

Lagarde P, Delaunay R, Flank AM, Jupille J (1993) Site of sulfur impurities in silicate glasses and REFLEXAFS studies around the Si -edge. Jap J Appl Phys 32 619-621 Lee PA, Citrin PH, Eisenberger PM (1981) Extended X-ray absoption fine structure-its strength and limitations as a structural tool. Rev Mod Phys 53 769-806 Lee JM, Yoo H-H, Joo M (1999) Numerical determination of a true absorption spectrum from grazing-incidence fluorescence EXAFS data. J Synchrotron Rad 6 244-246 Lieser KH, Flakowski M, Hoffman P (1994) Determination of trace elements in small water samples by total reflection X-ray fluorescence (TXRF) and by neutron activation analysis (NAA). Fresenius J Anal Chem 350 135-138... 

---