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Abstract  

There has been recent public concern over the use of organic arsenicals as medicaments and growth stimulators for poultry. In early studies, there was a correlation shown between the intake of arsenic and carcinogensis. Several investigators have strongly disputed these results. The purpose of this study was not to verify or discredit this carcinogenic theory but simply to determine if the arsenic levels in poultry could be measured using instrumental activation analysis. These analyses indicate that arsenic concentrations in poultry can be measured at levels below the mandatory maximum levels of arsenic in poultry.

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Abstract  

With the use of atomic and nuclear methods to analyze samples for a multitude of elements, very large data sets have been generated. Due to the ease of obtaining these results with computerized systems, the elemental data acquired are not always as thoroughly checked as they should be leading to some, if not many, bad data points. It is advantageous to have some feeling for the trouble spots in a data, set before it is used for further studies. A technique which has the ability to identify bad data points, after the data has been generated, is classical factor analysis. The ability of classical factor analysis to identify two different types of data errors make it ideally suited for scanning large data sets. Since the results, yielded by factor analysis indicate correlations between parameters, one must know something about the nature of the data set and the analytical techniques used to obtain it to confidentially isolate errors.

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Gamma-ray tables for neutron fast neutron and photon activation analysis

I. List of all the nuclides with their associated gamma-rays in order of increasing atomic number and mass

Journal of Radioanalytical and Nuclear Chemistry
Authors:
S. Lis
,
Ph. Hopke
, and
J. Fasching

Abstract  

In the past several years, a number of gamma-ray tables have been published. All of the tables limit themselves to those nuclides formed in (n, γ) reactions or at most to a few of the more prominent (n, 2n) products. A number of investigators are developing activation analysis methods using fast neutrons or photons. These investigations have been hampered by the lack of tables of gamma-rays of those nuclides that can be formed by (n, 2n), (n, p), (n, α), (n, n′) and (n, d) reactions. Since (γ, n) yields the same product as (n, 2n) the table would also be useful to photon activation studies. The authors have compiled such a table. Section II: list of the gamma-rays for all isotopes in order of increasing energy will be published in the J. Radioanal. Chem., 25 (1975) No. 2.

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Abstract  

In a study conducted in 1971, levels of tritium were found in Cattaraugus-Creek, a stream in Western New York State. This material was attributed to the operation in West Valley, New York of the world's first commercial nuclear fuels reprocessing plant. Several fission fragment isotopes in addition to tritium were also observed in Buttermilk Creek, one of the tributaries of Cattaraugus Creek that runs through the reprocessing plant grounds. The plant ceased processing nuclear fuel in December 1971, and a new set of measurements in these streams were made to assess the effect of the ending of the plant's operation. Substantially lower concentrations of tritium and no fission produced isotopes have been observed.

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Gamma-ray tables for neutron, fast-neutron and photon activation analysis

II. List of all the gamma-rays for all isotopes in order of increasing energy

Journal of Radioanalytical and Nuclear Chemistry
Authors:
S. Lis
,
Ph. Hopke
, and
J. Fasching
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Abstract  

Three hundred ancient Turkish potsherds were analyzed by instrumental neutron activation analysis, and the resulting data analyzed by several techniques of multivariate statistical analysis, some only recently developed. The programs AGCLUS, MASLOC, and SIMCA were sequentially employed to characterize and group the samples by type of pottery and by site of excavation or collection. Comparison of the statistical analyses by each method provided archaeological insight into the site/type relationships of the samples and ultimately evidence relevant to commercial relations between the ancient communities and to specialization of pottery production over time. The techniques used for statistical analysis were found to be of significant potential utility in the future analysis of other archaeometric data sets.

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Abstract  

In order to describe the occurrence and to investigate the sources of arsenic found in Chautauqua Lake sediments, 98 grab samples have been analyzed by neutron activation analysis. The arsenic concentrations were found to range from <0.5 to 58.75 ppm for 96 of the 98 samples with an overall average value of 22.10 ppm. The two other samples had concentrations of 140.0 and 306.0 ppm. High arsenic concentrations have been positively correlated with a decrease in the sediment particle size. Natural arsenic concentrations found in the soil and bedrock in the area do not explaint the observed concentrations in the lake sediment. The increase in arsenic appears to be related to the spraying of sodium arsenite as an aquatic pesticide during the period 1955–1963.

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Abstract  

Neutron activation analysis techniques were used to study sediments from Chautauqua Lake. The concentrations of Eu, Na, Mn, K, Br, As, Ga, La, Hf, Cs, Tb, Sc, Fe, Ta, Sb were determined and compared with similar data for the bedrock and soils surrounding the lake. The lake sediments are found to be enriched in Na, Mn, Br, As, Hf, Tb, Ta, and Sb relative to the surrounding source beds. High pairwise linear correlation coefficients (R∼0.9) were found between the concentrations of antimony, cesium, and scandium. For many elements a relationship was indicated between their concentrations and the clay fraction of the sediment, possibly due to the higher cation exchange potential of the clay minerals.

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