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Study of the material and techniques used by some nineteenth century American oil painters by means of neutron activation autoradiography

Description: Neutron activation autoradiography and activation analysis were used to study techniques and material used by nineteenth century painters particularly Ralph A. Blakelock. These techniques can supply information on pigments as well as the way they are applied. (LK)
Date: January 1, 1973
Creator: Cotter, M.J.; Meyers, P.; van Zelst, L.; Olin, C.H. & Sayre, E.V.
Partner: UNT Libraries Government Documents Department

Analytical comparison of various Egyptian soils, clays, shales, and some ancient pottery by neutron activation

Description: as a basis for classiftcation of clays and for tracing the origin of the parent materials used in pottery manufacturing, Nine pottery specimens were analyzed as a very preliminary test of the potential of correlation between clay and pottery compositions. (LK)
Date: January 1, 1973
Creator: Tobia, S.K. & Sayre, E.V.
Partner: UNT Libraries Government Documents Department

Compositional groupings of some ancient Aegina and eastern Mediterranean pottery

Description: From international conference on application of nuclear data in the field of work of art; Rome-Venice, Italy (24 May 1973). A difficult but most important problem in archaelogy and art history is that of establishing the origins of the various artifacts under study. In the case of pottery, much work has been done in recent years using neutron activation analysis to establish trace element patterns which in optimum instances may be used to match pottexy with the clay source from which it was manufactured. This paper gives some results of research carried out at Brookhaven National Laboratory involving neutron activation analysis of samples of potiery and clays from sources in Cyprus, the Aegean area, Palestine, and elsewhere in the Eastern Mediterranean, and the formation of groups of pottery specimens on the basis of these analyses. Some applications of multivariate methods to the problem of grouping the analytical data and some of the archaeological inferences which can be drawn from the data are also discussed. (auth)
Date: January 1, 1973
Creator: Bieber, A.M. Jr.; Brooks, D.W.; Harbottle, G. & Sayre, E.V.
Partner: UNT Libraries Government Documents Department

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

Analytical studies of ancient Egyptian glass

Description: Neutron activation analysis and emission spectroscopy were used to analyze ancient Egyptian glass. The emission spectroscopic method for determining Li, Na, K, Rb, Mg, Ca, Sr, Ba, B, Al, P, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zr, Ag, Sn, Sb, Pb, and Bi is described in the appendix. Neutron activation was used to determine Na, K, Rb, Ba, Sc, La, Ce, Eu, Lu, Hf, Th, Ta, Cr, Fe, Co, and Sb by a method described by Tobia and Sayre at the conference. (DHM)
Date: January 1, 1973
Creator: Sayre, E.V. & Smith, R.W.
Partner: UNT Libraries Government Documents Department

Correlation of radial bone mineral content with total-body calcium in various metabolic disorders

Description: From international conference on bone mineral measurement; Chicago, Illinois, USA (12 Oct 1973). Loss of bone mineral content of the skeleton in osteoporosis and in other metabolic disorders can be measured directly by totalbody neutron activation analysis (TBNAA). The densitometric technique (using monochromatic photons from /sup 125/I) applied to the appendicular skeleton (radius) also reflects the loss of bone mineral in osteoporosis. In the present study the results of these two techniques are compared in 80 patients with various metabolic disorders and in 9 normal contrast subjects. It is apparent that there is good correlation between total body calcium (TBCa) and bone mineral content (BMC) in all groups studied. The correlation was highest in the normal contrast group (0.97) and alcoholics(0.98) and lowest in osteoporotic patients (0.83) and in renal patients on dialysis (0.84). In order to measure the relative deficit in TBCa in individual patients from the absolute calcium measurement, it is necessary to normalize the data for sex, age, and skeletal size. For this purpose an algorithm was used to predict the normal skeletal Ca in each subject bascd on weight, height, sex and age. In similar manner, BMC data were normalized using the same algorithm. These normalization procedures allow both the TBCa and BMC measurement of the radius to be used to compare the Ca deficit in individuals with different metabolic disorders. (auth)
Date: January 1, 1973
Creator: Cohn, S.H.; Ellis, K.J.; Zanzi, I.; Letteri, J.M. & Aloia, J.
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

Detection systems for the low-level radiochemical analysis of iodine-131, iodine-129, and natural iodine in environmental samples

Description: A procedure based on chemicsl separation techniques and activation anslysis was developed for the sequential analysis of low levels of /sup 131/I, / Sup 129/I, and natural iodine in environmental samples. The iodine is first separated from the samples by oxidation. The separated iodine is then counted by low-level, beta-gated gamma spectrometry for the measurement of /sup 131/I. The chemical yield for the separation is measured by means of /sup 125/I tracer. Activation analysis is used for measurement of the separated natural iodine (/sup 127/I) and /sup 129/I. The natural iodine is estimated from either the /sup 126/ I or /sup 128/I activity produced in the sample; the induced /sup 130/I is used to estimate the /sup 129/I concentration. The measurement of /sup 130/I at low levels requires specialized counting methods. Interfering activities that may be present in the irradiated sample include /sup 125/I, /sup 126/I, short-lived fission-product iodine activities produced by activation of uranium impurities, and /sup 82/Br from bromine impurities. Since /sup 130/I decays with several coincident gamma rays, multiple gamma coincidence counting techniques can be used to reduce background and discriminate against interfering activities. Severail three- and four-segmented NaI(Tl) detectors were used for these measurements and compared with other detector systems. The sensitivities for different coincidence counting modes were compared for several of the detector systems. Detection sensitivities achieved for /sup 131/I and /sup 129/I are 0.02 dpm and 10/sup -6/ dpm, respectively. Meaeurements have been made of iodine radioactivity in the environment at concentrations below the limits established for radiation protection purposes. (auth) Twelve papers were presented at the symposium and separate abstracts have been prepared for seven of them. Five of the papers were previously abstracted for NSA and appeared as 26: 25164,
Date: October 26, 1973
Creator: Brauer, F.P. & Kaye, J.H.
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