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100 mg $sup 251$Cf activation analysis facility at the Savannah River Laboratory

Description: The $sup 252$Cf Activation Analysis Facility at the Savannah River Laboratory (SRL) is used routinely for multielement analyses of a wide variety of solid and liquid samples (e.g., metal alloys, fly ash and other airborne particles, rocks, and aqueous and nonaqueous solutions). An automated absolute activation analysis technique, developed to use neutron transport codes to calculate multienergy group neutron spectra and fluxes, converts counting data directly into elemental concentrations expressed in parts per million. The facility contains four sources of $sup 252$Cf totaling slightly over 100 mg. A pneumatic ''rabbit'' system permits automatic irradiation/decay/counting regimes to be performed unattended on up to 100 samples. Detection sensitivities of less than or equal to 400 ppb natural uranium and less than or equal to 0.5 nCi/g for $sup 239$Pu are observed. Detection limits for over 65 elements have been determined. Over 40 elements are detectable at the one part per million level or less. Overall accuracies of +- 10 percent are observed for most elements. (auth)
Date: January 1, 1975
Creator: MacMurdo, K.W. & Bowman, W.W.
Partner: UNT Libraries Government Documents Department

Data reduction in the 100 mg $sup 252$Cf activation analysis facility at the Savannah River Laboratory

Description: The automated absolute activation analysis technique developed at the Savannah River Laboratory is based on the ability to predict neutron capture reaction rates from tabulated cross sections and neutron spectra accurately calculated for the 100-mg $sup 252$Cf source. A series of computer programs comprises the data reduction system which: (1) reduces the gamma-ray spectra to lists of photopeak energies, areas, and statistical errors for all significant photopeaks, (2) assigns each gamma ray to the appropriate activation product by comparing experimental to tabulated gamma-ray energy, (3) converts each photopeak area into an elemental concentration using the experimental timing data, calculated reaction rates, detector efficiency, and activation product spectroscopic data in the absolute activation master equation. The data reduction system requires about one second of IBM 360-195 CPU time for the conversion of each 4096 channel spectrum into a qualitative and quantitative list of elemental composition. The accuracy of the algorithm is better than +- 15 percent for most elements. (auth)
Date: January 1, 1975
Creator: Bowman, W.W. & MacMurdo, K.W.
Partner: UNT Libraries Government Documents Department

Neutron activation analysis applied to energy and environment

Description: Neutron activation analysis was applied to a number of problems concerned with energy production and the environment. Burning of fossil fuel, the search for new sources of uranium, possible presence of toxic elements in food and water, and the relationship of trace elements to cardiovascular disease are some of the problems in which neutron activation was used. (auth)
Date: January 1, 1975
Creator: Lyon, W.S.
Partner: UNT Libraries Government Documents Department

Techniques for characterization of particulate matter: neutron activation analysis, x-ray photoelectron spectroscopy, scanning electron microscopy

Description: Three techniques for particulate matter analysis are discussed: (1) neutron activation, which is a method that samples the entire specimen, both surface and bulk; (2) electron spectroscopy for chemical analysis (ESCA), which samples particle surfaces only; and (3) scanning electron microscopy (SEM), which reveals particle size and morphology, and can be used to determine composition differences in individual particles. These three techniques can be combined to construct highly detailed characterizations of particulate matter specimens. It is shown that multielement analysis can be quickly done by neutron activation and that surface analysis and individual particle analysis obtained by ESCA and SEM, are very important supplementary information. (auth)
Date: January 1, 1975
Creator: Hulett, L.D.; Dale, J.M.; Emery, J.F.; Lyon, W.S. Jr. & Fulkerson, W.
Partner: UNT Libraries Government Documents Department

Elemental analysis of water and air solids by neutron activation analysis

Description: Instrumental neutron activation analysis was used to determine the elemental concentrations in water and air solids samples collected on Nucleopore and Whatman filters from the Walker Branch Watershed. The results from this study show that the trace element concentrations removed by water from the watershed vary seasonally, as well as geographically. The data point up the usefulness and versatility of absolute neutron activation analysis. The NBS Standard Orchard Leaves were assayed in a similar manner, and good agreement was obtained between results here and standard values. (auth)
Date: January 1, 1975
Creator: Bate, L.C.; Lindberg, S.E. & Andren, A.W.
Partner: UNT Libraries Government Documents Department

Provenance studies of Sgraffiato and Late Green Glazed wares from Siraf, Iran

Description: Results of neutron activation analyses of 23 elements in ceramic archaeological specimens are given. Various wares are divided into the following categories: early Sgraffiato, late Sgraffiato, late Green A, late Green B, and Samarra ware. Results are given on the following elements: Al, Ca, Dy, Mn, Na, K, U, Sm, La, Ti, Lu, Co, Sc, Fe, Cs, Cr, Ni, Eu, Ce, Hf, Ta, Th, and Yb. (JGB)
Date: March 1, 1975
Creator: Michel, H.V.; Asaro, F. & Frierman, J.D.
Partner: UNT Libraries Government Documents Department