Neutron activation and

Three common quantitative applications of radiochemical methods of analysis are considered in this section the direct analysis of radioactive isotopes by measuring their rate of disintegration, neutron activation, and the use of radioactive isotopes as tracers in isotope dilution. 

Several radiochemical studies have been reported, such as the analysis of phosphorus and chlorine by fast neutron activation and synthesis by radiochemical methods. ... 

Given these requirements, it emerges that a suitable analytical technique for studying provenance should provide relatively rapid results and preferably be nondestructive, enabling determination of each element, and differentiation among a large number of elements in relatively short periods of time. Techniques that fulfill these conditions for studying the provenance of pottery include several spectroscopic techniques, neutron activation and X-rays fluorescence (see Textbox 10). 

Hughes, M.J., Cowell, M.R. and Hook, D.R. (1991a). Neutron Activation and Plasma Emission Spectrometric Analysis in Archaeology. British Museum Occasional Paper 82, London. 

Calcium may be analyzed by several instrumental techniques such as atomic absorption and emission spectrophotometry, ICP—MS, neutron activation, and x-ray fluorescence and diffraction methods. For all these techniques,... 

Lutetium occurs in nature in small amounts in yttrium-containing minerals. It is found in xenotime, precambrian granites, and North American shales. It also exists at 0.001% in monazite, from which the metal is produced commercially. Lutetium has very httle commercial apphcation. The metal emits beta particles after thermal neutron activation, and is used to catalyze organic reactions. 

Molybdenum may be identified at trace concentrations by flame atomic absorption spectrometry using nitrous oxide-acetylene flame. The metal is digested with nitric acid, diluted and analyzed. Aqueous solution of its compounds alternatively may be chelated with 8—hydroxyquinobne, extracted with methyl isobutyl ketone, and analyzed as above. The metal in solution may also be analyzed by ICP/AES at wavelengths 202.03 or 203.84 nm. Other instrumental techniques to measure molybdenum at trace concentrations include x-ray fluorescence, x-ray diffraction, neutron activation, and ICP-mass spectrometry, this last being most sensitive. 

Carbon and hydrogen were determined by a microcombustion method and nitrogen by a micro-Kjeldahl method. The oxygen in the total samples was determined by neutron activation and that in the fractions by... 

Normal values of aluminum in whole blood have been reported to range from 0.14 to 6.24 mg/L (ppm), and in plasma from 0.13 to 0.16 mg/L (ppm) (Sorenson et al. 1974). Normal values in serum have been reported at 1.46 and 0.24 mg/L (ppm), using neutron activation and atomic absorption analysis, respectively (Berlyne et al. 1970). A normal value of 0.037 mg/L (ppm) for serum using flameless atomic absorption analysis has also been reported (Fuchs et al. 1974). Drablos et al. (1992) analyzed aluminum serum levels in 230 nonexposed workers (controls) and reported a mean aluminum serum level of 0.005 0.002 mg/L (ppm). Research has shown that the levels of aluminum in the serum in the general population do not exceed 0.01 mg/L (ppm) (Cornells 1982). Nieboer et al. (1995) reviewed 34 studies on aluminum levels in serum or plasma, and also reported that aluminum serum levels in the general population were typically <0.01 mg/L (ppm). 

The latexes were ion-exchanged with Dowex 50W(H+) resin and the Dowex 50W(H+)-Dowex 1 (0H ) mixed resin in combination with the Dowex 50W(Na" ")-Dowex 1 (0H ) resin, and the ion-exchanged samples were titrated conductometrically. The samples treated were the latex, the aqueous serum, the latex particles separated from the serum, and the latex particles swollen or dissolved in 80 20 dioxane-water mixture. The total oxygen content was determined by neutron activation and the total sulfur content by X-ray fluorescence. Material balances of acrylic or methacrylic acid found in the serum, on the particle surface, and inside the particle agreed with the amount added to within 5-10%. 

Fujii et al. 7 8> have developed a rapid method for the determination of praseodymium, using 14 MeV neutron activation and gamma-gamma coincidence counting. 

Rancitelli, L. A., J. A. Cooper, and R, W. Perkins The Multielement Analysis of Biological Material by Neutron Activation and Direct Instrumental Techniques. The 1968 International Conference Modern Trends in Activation Analysis Gaithersburg, Maryland, October 7—11, 1968, Paper 136. 

Neutron activation and petrographic analysis of late medieval Spanish pottery from the major Spanish production centers of Seville, Granada, Patema-Manises, Barcelona, and Talavera-Puente allowed progress to be made in uniquely characterizing these production centers (5-7). Efforts to identify different Mexican majolica productions petrographically have been unsuccessful, and an attempt at chemical characterization by directly coupled plasma-optical emission spectroscopy was later determined to have been flawed by problems encountered with the dissolution of the ceramic samples... 

Techniques for analysis and sample preparation have been developed for using spark source mass spectrometry (SSMS) to study archaeological samples. Comparative studies of neutron activation and SSMS on identical samples have been made. The technique is used to determine the ores of origin of two series of early Peruvian artifacts. 

In selecting the materials ( W), major emphasis is given to neutron activation and radiation damage effects in materials close to the plasma and further considerations are given to other factors such as corrosion, long-term creep strength, fabrication technology, and cost. 

Variations of Elements in the Lithologic Sequence. The results of the neutron activation and x-ray fluorescence analysis for the stratigraphic sequence are listed in Table IV. 

APDC = ammonium pyrroiidine dithiocarbamate Bq = Bequerei and 1 pCi = 0.37 Bq dpm = disintegration per minute and 1 pCi = 2.22 dpm EDTA = ethyienediaminetetraacetic acid Fi = fiow injection HPLC=high performance liquid chromatography ICP = inductively coupled plasma spectrometry INAA = instrumental neutron activation and analysis MS = mass spectrometry NAA = neutron activation analysis nM = nanomole or 10 of a mol... 

In addition to the human labor problems created by chemical separation and ultra-clean environments, both neutron activation and thermal Ionization mass spectrometry require unique equipment that Is not available to most research groups. Because of these factors progress In trace metal analysis has been slow and practical data acquisition from large populations Is essentially non-existent ... 

Table VIII. Estimated l-o- Precision of Trace Element Analyses by Neutron Activation and X-Ray Fluorescence...

Analytical methods characterized by good precision and sensitivity are necessary so that analytical errors will not add to other errors in diflBcult sampling situations, and so that the true magnitude of differences caused by process and feedstock variables can be measured. In complex samples, high precision inorganic analyses are facilitated by techniques such as neutron activation and x-ray fluorescence which are relatively insensitive to matrix effects. 

The bulk of the published work on activation analysis has been concerned with neutron activation and this, the more general technique, wall be dealt with in some detail. A tivation with charged particles will be considered in Section VII. 

Brunfelt, A. O., Steinnes, E. Determination of lutetium, ytterbium and terbium in rocks by neutron activation and mixed solvent anion-exchange chromatography. Analyst 94, 979 (1969)... 

Bard, J.C. (1979) The development of a patination dating technique for Great Basin petroglyphs utilizing neutron activation and X-ray fluorescence analyses. PhD dissertation, Department of Anthropology, University of California, Berkeley. 

Mousty F, Omenetto N, Pietra R, et al. 1984. Atomic-absorption spectrometric, neutron-activation and radioanalytical techniques for the determination of trace metals in environmental, biochemical and toxicological research. Part I. Vanadium. Analyst 109 1451-1454. 

GPC (total radioactive strontium) = beta gas proportional counter Bq = Becquerel dpm = disintegrations per minute EDTA = ethylenediamine tetraacetic acid GFAAS (total strontium) = graphite furnace atomic absorption spectroscopy ICP-AES (total strontium) = inductively coupled plasma atomic emission spectroscopy ICP-MS (isotopic strontium composition) = inductively coupled plasma-mass spectrometry LSC (isotopic quanitification of 89Srand 90Sr) = liquid scintillation counting pCi = pico curies (10-12 curies) PIXE (total strontium) = proton induced x-ray emission TMAH = tetramethylammonium hydroxide TNA (total strontium) = thermal neutron activation and radiometric measurement TRXF (total strontium) = total-reflection x-ray fluorescence... 

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