Performance of NAA Methods in an International Interlaboratory Reference Material Characterization Campaign

An extensive database of analytical results from a recent biological matrix Reference Material Characterization Campaign permitted an intercomparison of the performances of various methods among each other and with "true" best estimate concentration values established for these materials. Six different variants of neutron activation analysis (NAA) methods were employed including: instrumental neutron activation analysis, instrumental neutron activation analysis with acid digestion, neutron activation analysis with radiochemical separation, neutron capture prompt gamma activation analysis, epithermal instrumental neutron activation analysis, and neutron activation analysis with preconcentration. The precision and accuracy performance of NAA-based analytical methods are compared with three other major techniques, atomic absorption spectrometry (AAS), atomic emission spectrometry (AES) and mass spectrometry (MS) for 28 elements in 10 natural matrix materials.     

Determination of vanadium in high grade carbons by radioanalytical methods

The present work deals with the determination of vanadium in high grade carbons by three radioanalytical methods, viz. thermal neutron activation analysis with an accelerator, thermal neutron activation analysis with a reactor and proton induced X-ray emission analysis with an accelerator. It is cleared from this study that thermal neutron activation with an accelerator is more convenient for the rapid and non-destructive analysis of ppm-level vanadium in bulk carbons than thermal neutron activation analysis with a reactor. Proton induced X-ray emission is less useful for the analysis of bulk samples.     

Instrumental multielement activation analysis of soil samples

Soil samples from a waste water cleaning facility in Berlin, Germany, have been analyzed using several activation analysis methods. 43 elements have been determined by instrumental high energy photon activation analysis (PAA), instrumental thermal neutron activation analysis (NAA) and 14 MeV neutron activation analysis (fNAA). Conventional gamma ray spectroscopy and low energy photon spectroscopy (LEPS) have been applied for product activity measurement. It has turned out that these methods in combination offer a wide spectrum of analytical information.     

Activation analysis: Present status in relation to other analytical techniques

Recent developments and trends in activation analysis are reviewed. Instrumental and radiochemical neutron activation analysis, as well as charged particle activation analysis are considered. The present status of activation analysis is summarised and compared to inductively coupled plasma mass spectrometry. Some examples of recent applications are given.     

The Status of Activation Analysis in Archaeology and Geochemistry

Many of the initial applications for activation analysis occurred in the fields of archaeology, geochemistry and cosmochemistry. In addition to the desire to investigate noteworthy problems of interest to these disciplines, the reasons for employing activation analysis were based on the advantages of sample preparation, sensitivity, multi-element capability, and non-destructiveness. Nearly fifty years later and despite the development of several new analytical methods, we find that many of these same advantages continue to attract interest in activation analysis from these same disciplines. This overview discusses the past, present and future role of activation analysis with regard to research questions in archaeology, geochemistry, and cosmochemistry.     

Determination of trace elements in various materials by activation analysis

Recent works on the trace analysis of various materials by activation analysis are summarized. INAA and IPAA are applied for the multielement determination of various standard reference materials and electronic materials. As an example, the analytical results of pepperbush and fluoride glass are shown. In activation analysis using chemical separation, the destructive neutron activation analysis coupled with isotope addition technique is presented and applied to the determination of trace impurities in indium phosphide. Selective substoichiometry and substoichiometric separagtions of some elements are also introduced.     

Methodological developments and applications of neutron activation analysis

The paper reviews the author’s experience acquired and achievements made in methodological developments of neutron activation analysis (NAA) of mostly biological materials. These involve epithermal neutron activation analysis, radiochemical neutron activation analysis using both single-and multi-element separation procedures, use of various counting modes, and the development and use of self-verification principle. The role of NAA in the detection of analytical errors is discussed and examples of applications of the procedures developed are given.     

Neutron activation analysis of the rare earth elements in rocks from the earth's upper mantle and deep crust

Three techniques for analyzing rare earth elements (REE) in geological materials are described, i.e. instrumental neutron activation analysis (INAA), neutron activation analysis with pre-irradiation chemical REE separation (PCS-NAA) and radiochemical neutron activation analysis (RNAA). The knowledge of REE concentrations in eclogites, peridotites and minerals from the earth's lower crust and upper mantle is very useful in constraining their petrogenetic history.     

Rapid analysis of biological reference materials by instrumental neutron activation

Summary Instrumental neutron activation analysis (INAA) was applied to the rapid determination of cadmium and other elements in the IAEA biological reference material horse-kidney (H-8). Nuclear reactor neutrons and epithermal neutrons were used as neutron sources. Cadmium, bromide, iodine and phosphorus were determined by epithermal neutron activation analysis. Aluminum was determined by reactor neutron activation analysis taking into account the contribution of phosphorus to the ²⁸Al activity.     

Quantitative evaluation of interference reactions in photon activation analysis

Interferences of different types (competing reactions, overlapping photons emission energies etc.) occur more frequently during activation analysis with high energy exciting radiation that in conventional thermal neutron activation. Three main types of interference in high energy photon activation analysis (PAA) have been determined quantitatively, using experimentally obtained data exclusively. Based on the results presented, it is possible in many critical cases to improve significantly the accuracy of analysis results obtained by PAA.     

Application of the single comparator method to instrumental photon activation analysis

Journal of Radioanalytical and Nuclear Chemistry - Instrumental photon activation analysis (IPAA) is nondestructive and multi-elemental analysis method like instrumental neutron activation...     

A cyclic neutron activation system using an isotopic neutron source for the measurement of short-lived isotopes

The design and construction of an activation analysis system using an isotopic neutron source which allows the measurement of prompt and delay gamma-rays, in conventional activation and cyclic activation modes, is briefly described with emphasis laid on its flexibility, transportability and low cost. Photon spectra obtained from the irrdiation of large samples under prompt, delay and cyclic conditions using both NaI(Tl) and Ge(Li) detectors are presented and described with respect to ‘in-vivo’ neutron activation analysis and the measurement of N, O, Na, P, Cl and Cd. It is pointed out that, despite the attractive possiblity of measuring Se in liver, ‘in-vivo’, by cyclic activation analysis, the system may potentially prove a very useful tool for industrial and other non-medical applications.     

Application of short time activation analysis in the sciences

Short time activation analysis was applied to the analysis of reactor emergency poisoning solutions, to the analysis of doping elements in small organic semiconductor specimens, for the analysis of high temperature superconductors, and the determination of fluorine in various materials including biopsy samples. All the halogens in waste water were analyzed by a single 20s activation followed by two successive counting periods of 20 and 200s.     

Proton, Photon and Neutron Activation Analysis for the Determination of Stable Isotopes of Gadolinium in Human Blood Plasma

The biokinetics of radioactive substances can be studied using stable tracers. For the highly radiotoxic actinides, for which no stable isotopes are available as tracers, the use of stable isotopes of lanthanides as chemically related surrogates has been suggested. In this work, the possibility of using activation analysis with protons, photons, or thermal neutrons for the determination of single stable isotopes of gadolinium in biological samples has been tested. All the techniques show very good linearity response, and may be considered as complementary. Whereas activation analysis with protons is recommendable for the simultaneous determination of two different isotopes, neutron and photon (gamma) activation analysis should be chosen whenever a better sensitivity or simplicity of the analysis is required.     

Simultane instrumentelle Multielementbestimmung in antiker Keramik (Terra Sigillata) durch Aktivierungsanalyse mit hochenergetischen Photonen

A large number of fragments of ancient roman pottery has been analyzed for main constituents, minor and trace-elements using high-energetic photon activation analysis followed by high resolution gamma spectroscopy. Especially the environmental influence on the concentrations of the minor constituents and trace elements during deposition of the sherds in the soil has been examined. Finally, a comparison has been made between analysis data of ancient pottery obtained by photon activation analysis, X-ray fluorescence analysis and 14 MeV-neutron activation analysis.      

The use of a high efficiency mass separator in activation analysis

The application of high yield mass separators to problems in activation analysis is discussed. The identification of separation parameters including separator yields, memory, resolution and overlap, and sputtering are considered. The use of the mass separator in determining lead by photon activation analysis is described.     

Comparison of Three Techniques for Rapid Determination of Strontium in Soils and Vegetation

Abstract

Instrumental epithermal neutron activation analysis, atomic absorption spectrophotometry, and instrumental thermal neutron activation analysis were compared to determine which technique produced best Sr data in the most expeditious fashion. Irradiation with epithermal neutrons was found to be the best method.     

Methods and equipment of industrial activation analysis

Expanding application of activation analysis in industry resulted in exposure of features related to higher requirements to productivity, reliability, automation level, metrological support of analytical methods and equipment. Based on the application of neutron generators, radioisotope neutron sources, nuclear reactors, electron accelerators as activating radiation sources, high-productivity activation analytical systems used directly in analytical laboratories and plants were constructed. Level of development of the above works makes it possible to conclude that industrial activation analysis has formed as an independent trend of nuclear analytics and has considerable prospects.