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Abstract  

Exploration and modification of data for k 0-PGAA (prompt γ-ray activation analysis) values used as standards for k 0 standardization are needed. An integrated system has been installed and calibrated in Hot Laboratories Center for PGAA, using 252Cf isotopic neutron source with neutron flux of 6.16E8 n/cms. The prompt k 0-factors of about 12 elements were determined versus the 1951.1 keV γ-ray of the 35Cl, as well as analyzing crude oil and oil product samples. The concentrations of the elements in crude oil H, B, Mg, Al, Na, Si, P, S, Cl, V and Cd were 1.18E5, 0.084, 5.48E2, 8.45E2 4.88E2, 1.62E2, 3.72E2, 8.2, 144.3, 393 and 209.2 ppm while in oil product samples were 1.32E5, 5.87, 4.56E2, 4.22E2, 7.16E3, 699, 157, 8.74, 492.3, 61 and 198.2 ppm. Validation of the k 0-PGAA was applied in analyzing standard IAEA reference material (soil-7) which give good agreement with the literature data. The 252Cf neutron beam in radiation position was characterized by the cadmium-ratio method, and found that the cadmium ratio (f), was 160.

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Abstract  

A prompt gamma neutron activation analysis facility has been designed, built, and characterized at the Oregon State University TRIGA® reactor. This facility was designed for versatile multi-elemental analyses. The facility utilizes the leakage neutrons originating from beam port #4 of the Oregon State University TRIGA® reactor. The neutrons are collimated through a series of lead and Boral® collimators, and filtered through both a bismuth filter and single-crystal sapphire. Samples are irradiated in a sample chamber outside the biological shielding of the reactor, and the resulting gamma radiation produced from neutron interactions within the sample is monitored using a high-purity germanium detector (HPGe). The thermal and epithermal neutron fluxes were measured using gold-foil irradiations and found to be 2.81 × 107 and 1.70 × 104 cm−2 s−1, respectively. The resulting cadmium ratio was 106. Measured detection limits for boron, chlorine, and potassium in a NIST SRM 1571 orchard leaf were 5.6 × 10−4 mg/g, 8.2 × 10−2 mg/g, and 1.0 mg/g, respectively. Detection limits for additional elements and samples are presented.

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patina and corrosion products. 3 Since sampling and sample preparation were prohibited in this study, prompt-gamma activation analysis (PGAA) technique 4 and Time-of-Flight Neutron Diffraction (TOF-ND) 5 were used to determine the composition, and for

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Abstract  

Since 1996 several applications of prompt gamma activation analysis have been performed at the new Budapest PGAA facility. This paper deals with the investigation of metal objects. We report the results of nondestructive detection of H in amorphous metals, multielement analysis of Roman bronze brooches and measurement of silver concentration in Hungarian coins.

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Abstract  

Recommended k0-factors and related nuclear data for use in (n, ) activation analysis are given for 72 isotopes. In addition the basic nuclear constants and experimental parameters needed in the k0 standardization method are reviewed. For convenient data reduction, computer programs were developed.

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Abstract  

The prompt -activation analysis (PGAA) facility at Budapest Research Reactor offers a unique possibility to perform in-beam measurements. Several k 0 factors for decay -lines of short-lived nuclides have been determined accurately by means of in-beam activation. The present values compare well with literature data. New k 0 factors are proposed for 24mNa and 60mCo.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: T. Belgya, Z. Kis, L. Szentmiklósi, Zs. Kasztovszky, G. Festa, L. Andreanelli, M. De Pascale, A. Pietropaolo, P. Kudejova, R. Schulze, and T. Materna

Abstract  

Prompt gamma activation analysis (PGAA) is a well known tool for non-destructive bulk elemental analysis of objects. The measured concentrations are only representative of the whole sample if it is homogenous; otherwise it provides only a sort of average composition of the irradiated part. In this latter case one has to scan the sample to obtain the spatial distribution of the elements. To test this idea we have constructed a prompt gamma activation imaging — neutron tomograph (PGAI-NT) setup at the NIPS station of the Budapest Research Reactor, consisting of a high-resolution neutron tomograph and a germanium gamma-spectrometer. The samples are positioned relative to the intersection of the collimated neutron beam and the projection of the gamma-collimator (isocenter) by using an xyzω-moving table.

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Abstract  

Nuclear Analytical Chemistry at Texas A&M University is based in large part on the facilities of the Center for Chemical Characterization and Analysis and the Nuclear Science Center. This paper describes the capabilities of these two centers for instrumental and fast neutron activation analysis, neutron depth profiling, prompt gamma activation analysis, neutron radiography and the unique features of the large volume irradiation cell and reactor pulsing operation.

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Abstract  

The concept of the effective resonance energy
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $$\bar E_r$$ \end{document}
, formerly introduced as a parameter in the absolute (e.g. k0-) standardization methodology of (n, ) activation analysis, is elucidated with respect to dimensioning, accuracy and usefulness.
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Abstract  

Prompt-gamma activation analysis (PGAA) differs from conventional neutron activation analysis in the set of elements measured, the irradiation conditions, and the nature of the gamma-ray spectra. Each of these affects the conduct of the measurements and interpretation of the data. In its recent development, the k 0 standardization framework provides a solution to many of the problems of this analytical method, and may provide a bridge to greater certainty of analysis.

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