Instrument neutron activation analysis

Atomic absorption spectroscopy of VPD solutions (VPD-AAS) and instrumental neutron activation analysis (INAA) offer similar detection limits for metallic impurities with silicon substrates. The main advantage of TXRF, compared to VPD-AAS, is its multielement capability AAS is a sequential technique that requires a specific lamp to detect each element. Furthermore, the problem of blank values is of little importance with TXRF because no handling of the analytical solution is involved. On the other hand, adequately sensitive detection of sodium is possible only by using VPD-AAS. INAA is basically a bulk analysis technique, while TXRF is sensitive only to the surface. In addition, TXRF is fast, with an typical analysis time of 1000 s turn-around times for INAA are on the order of weeks. Gallium arsenide surfaces can be analyzed neither by AAS nor by INAA. 

Neutron Activation Analysis Instrumental Neutron Activation Analysis... 

Kucera j, Soukal L (1988) Homogeneity tests and certification analyses of coal fly ash reference materials by instrumental neutron activation analysis. J Radioanal Nucl Chem Articles 121 245-259. 

Tu Shu-Db, Lieser KH (1984) Homogeneity test of Chinese biological standard reference materials by means of instrumental neutron activation analysis, f Radioanal Nucl Chem Articles 84 301-306. 

Although sophisticated methods may constitute the core methods for certification it is useful to include good, well executed routine methods. In order to further minimize systematic error, a conscious purposeful attempt should be made to get methods and procedures with wide-ranging and different sample preparation steps, including no decomposition as in instrumental neutron activation analysis and particle induced X-ray emission spectrometry. 

Kucera J, and Soukal L (1998) Low uncertainty determination of manganese and vanadium in environmental and biological reference materials by instrumental neutron activation analysis. Fresenius J Anal Chem 360 415-418. 

Wandless GA (1993) Instrumental neutron activation analysis of Devonian Ohio Shale SDO-i. 

The characteristics of radiochemical methods are well known [435]. An overview of the determination of elements by nuclear analytical methods has appeared [436]. Some selected reviews of nuclear methods of analysis are available charged particle activation analysis [437,438], instrumental neutron activation analysis [439-441] and ion-beam analysis [442]. 

Bishop, R. L. and M. J. Blackman (2002), Instrumental neutron activation analysis of archaeological ceramics Scale and interpretation, Acc. Chem. Research 35(8), 603-610. 

Williams-Thorpe, O., S. E. Warren, and J. G. Nandis (1997), Characterization of obsidian sources and artefacts from central and eastern Europe, using instrumental neutron activation analysis, in Korek, J. (ed.), Proc. Int. Conf. Lithic Raw Material Characterization, Budapest and Siimeg, 1996, Budapest. 

The chemistry of rare earth elements makes them particularly useful in studies of marine geochemistry [637]. But the determination of rare earths in seawater at ultratrace levels has always been a difficult task. Of the various methods applied, instrumental neutron activation analysis and isotope dilution mass spectrometry were the main techniques used for the determination of rare earths in seawater. However, sample preparation is tedious and large amounts of water are required in neutron activation analysis. In addition, the method can only offer relatively low sample throughputs and some rare earths cannot be determined. The main drawbacks of isotopic dilution mass spectrometry are that it is time-consuming and expensive, and monoisotopic elements cannot be determined as well. 

Karbe, L., C. Schnier, and H.O. Siewers. 1977. Trace elements in mussels (Mytilus edulis) from coastal areas of the North Sea and the Baltic. Multielement analysis using instrumental neutron activation analysis. Jour. Radioanal. Chem. 37 927-943. 

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

WVGES has not had analytical laboratory facilities since the 1970 s so contract geochemical analyses are a necessity. After considering a variety of sources for analytical work including both university and government laboratories, we decided to use a commercial lab, located in Ontario, which specializes in analyses for the mineral exploration industry (they have since expanded into the environmental field as well). For the sake of consistency, each sample is analyzed using the same set of techniques, a combination of Instrumental Neutron Activation Analysis (INAA) and Selective Extraction-Ignition Coupled Plasma spectroscopy that yield results for 49 elements - Au, Ag, As, Ba, Br, Ca, Co, Cr, Cs, Fe, Hf, Hg, Ir, Mo, Na, Ni, Rb, Sb, Sc, Se, Sn, Sr, Ta, Th, U, W, Zn, La, Ce, Nd, Sm, Eu, Tb, Yb, Lu, Cu, Pb, Mn, Cd,... 

Allen, R.O., Luckenbach, A.H. and Holland, C.G. (1975). The application of instrumental neutron activation analysis to a study of prehistoric steatite artifacts and source material. Archaeometry 17 69-83. 

Pavlish, L.A., Hancock, R.G.V. and Ross, B. (2004). Instrumental neutron activation analysis of copper-rich samples from the Bead Hill site, Ontario, Canada. Historical Metallurgy 38 106-112. 

Bakraji, E. H., Othman, I., Sarhil, A., and Al-Somel, N. (2002). Application of instrumental neutron activation analysis and multivariate statistical methods to archaeological Syrian ceramics. Journal of Trace and Microprobe Techniques 20 57-68. 

Descantes, C., Neff, H., Glascock, M. D., and Dickinson, W. R. (2001). Chemical characterization of Micronesian ceramics through instrumental neutron activation analysis a preliminary provenance study. Journal of Archaeological Science 28 1185-1190. 

Garcia-Heras, M., Blackman, M. J., Fernandez-Ruiz, R., and Bishop, R. L. (2001). Assessing ceramic compositional data a comparison of total reflection X-ray fluorescence and instrumental neutron activation analysis on Late Iron Age Spanish Celtiberian ceramics. Archaeometry 43 323-347. 

Kuleff, I. and Pernicka, E. (1995). Instrumental neutron activation analysis of native copper - some methodological considerations. Journal of Radioanalytical and Nuclear... 

Moreau, J.-F. and Hancock, R. G. V. (1996). Chrono-cultural technique based on the instrumental neutron activation analysis of copper-based artifacts from the contact period of northeastern North America. In Archaeological Chemistry organic, inorganic and biochemical analysis, ed. Orna, M. V., ACS Symposium Series 625, Washington, DC, American Chemical Society, pp. 64-82. 

Zheng, J., Goessler, W., Geiszinger, A., et al. (1997). Multi-element determination in earthworms with instrumental neutron activation analysis and inductively coupled plasma mass spectrometry a comparison. Journal of Radioanalytical and Nuclear Chemistry 223 149-155. 

Chemically pure reagents were used. Cadmium was added as its sulfate salt in concentrations of about 50 ppm. Lanthanides were added as nitrates. For the experiments with other metal ions so-called "black acid from a Nissan-H process was used. In this acid a large number of metal ions were present. To achieve calcium sulfate precipitation two solutions, one consisting of calcium phosphate in phosphoric acid and the other of a phosphoric acid/sulfuric acid mixture, were fed simultaneously in the 1 liter MSMPR crystallizer. The power input by the turbine stirrer was 1 kW/m. The solid content was about 10%. Each experiment was conducted for at least 8 residence times to obtain a steady state. During the experiments lic iid and solid samples were taken for analysis by ICP (Inductively Coupled Plasma spectrometry, based on atomic emission) and/or INAA (Instrumental Neutron Activation Analysis). The solid samples were washed with saturated gypsum solution (3x) and with acetone (3x), and subsequently dried at 30 C. The details of the continuous crystallization experiments are given in ref. [5]. 

With analytical methods such as x-ray fluorescence (XRF), proton-induced x-ray emission (PIXE), and instrumental neutron activation analysis (INAA), many metals can be simultaneously analyzed without destroying the sample matrix. Of these, XRF and PEXE have good sensitivity and are frequently used to analyze nickel in environmental samples containing low levels of nickel such as rain, snow, and air (Hansson et al. 1988 Landsberger et al. 1983 Schroeder et al. 1987 Wiersema et al. 1984). The Texas Air Control Board, which uses XRF in its network of air monitors, reported a mean minimum detectable value of 6 ng nickel/m (Wiersema et al. 1984). A detection limit of 30 ng/L was obtained using PIXE with a nonselective preconcentration step (Hansson et al. 1988). In these techniques, the sample (e.g., air particulates collected on a filter) is irradiated with a source of x-ray photons or protons. The excited atoms emit their own characteristic energy spectrum, which is detected with an x-ray detector and multichannel analyzer. INAA and neutron activation analysis (NAA) with prior nickel separation and concentration have poor sensitivity and are rarely used (Schroeder et al. 1987 Stoeppler 1984). 

Landsberger S, Jervis RE, Kajrys G, et al. 1983. Characterization of trace elemental pollutants in urban snow using proton induced x-ray emission and instrumental neutron activation analysis. Int J Environ Anal Chem 16 95-130. 

T.P. Cheng, H.D. Anderson, D.S. Mills, V.L. Spate, C.K. Baskett, J.S. Morris, Determination of the fluoride distribution in rabbit bone using instrumental neutron activation analysis, J. Radioanal. Nucl. Chem. 217 (1997) 171-174. 

First, we analyzed samples for a large number of elements to Identify any elements, regardless of toxicity or typical concentration, that would provide signals for the presence of material from certain types of sources. Both ambient samples and particles from sources were analyzed by Instrumental neutron activation analysis (INAA), by which one can often measure about 35 elements In Individual samples (17), As the Important elements Pb, N1 and Cd are not consistently, If ever, observed by INAA, they were often measured by other methods. As INAA Is sensitive to very small amounts of obscure elements, we have obtained reliable data for elements such as Ga, Hf, Sc, In, W and many rare earths which pose no known health hazard at present levels and contribute Insignificant amounts of mass to TSP. However, as discussed below, many trace elements have already been shown to be Important In receptor... 

Improved control devices now frequently installed on conventional coal-utility boilers drastically affect the quantity, chemical composition, and physical characteristics of fine-particles emitted to the atmosphere from these sources. We recently sampled fly-ash aerosols upstream and downstream from a modern lime-slurry, spray-tower system installed on a 430-Mw(e) coal utility boiler. Particulate samples were collected in situ on membrane filters and in University of Washington MKIII and MKV cascade impactors. The MKV impactor, operated at reduced pressure and with a cyclone preseparator, provided 13 discrete particle-size fractions with median diameters ranging from 0,07 to 20 pm with up to 6 of the fractions in the highly respirable submicron particle range. The concentrations of up to 35 elements and estimates of the size distributions of particles in each of the fly-ash fractions were determined by instrumental neutron activation analysis and by electron microscopy, respectively. Mechanisms of fine-particle formation and chemical enrichment in the flue-gas desulfurization system are discussed. 

In this work, we use a University of Washington low pressure impactor (LPI) and instrumental neutron activation analysis (INAA) to determine the elemental composition of aerosols from a two 430 MWe coal-utility boilers, ranging in diameter from less than 0.07 to about 10 )Jm, and to investigate the modification of the aerosol by a modern flue-gas desulfurization system. A preliminary account of the work is presented here. 

All impactor and filter samples were analyzed for up to 45 elements by instrumental neutron activation analysis (INAA) as described by Heft ( ). Samples were irradiated simultaneously with standard flux monitors in the 3-MW Livermore pool reactor. The x-ray spectra of the radioactive species were taken with large-volume, high-resolution Ge(Li) spectrometer systems. The spectral data were transferred to a GDC 7600 computer and analyzed with the GAMANAL code (1 ), which incorporates a background-smoothing routine and fits the peaks with Gaussian and exponential functions. 

We have operated the University of Washington MKV impactor as a low-pressure impactor to provide for chemical analysis, four discretely sized fly-ash fractions in the sub-half-micrometer- diameter aerosol accumulation region. Instrumental neutron activation analysis provided the sensitivity to determine accurately the concentrations of 28 major, minor, and trace elements with sufficient precision to reveal fine structure in the elemental distributions that might be missed by techniques of lesser accuracy and precision. 

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