• Title/Summary/Keyword: Neutron activation

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A STUDY ON KOREAN ANTHRACITE BY INSTRUMENTAL NEUTRON ACTIVATION ANALYSIS

  • Kim, N.B.;Woo, H.J.;Lee, K.Y.;Hong, W.;Chun, S.K.;Park, K.S.
    • 분석과학
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    • 제7권4호
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    • pp.477-482
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    • 1994
  • 2개 광산의 무연탄을 Co와 Au 비교체를 사용한 비파괴 중성자 방사화분석법으로 분석하여 31개 원소들의 함량을 구했다. 각 원소의 평균 함량과 함량 범위를, 그리고 광산의 원소별 함량 차이를 제시하였다. 또한 희토류 원소들의 원자량에 따른 함량 분포의 경향과 광상의 깊이에 따른 원소들의 함량 변화를 제시하였다.

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Origin of Spherule Samples Recovered from Antarctic Ice Sheet-Terrestrial or Extraterrestrial?

  • Sekimoto, Shun;Kobayashi, Takayuki;Takamiya, Koichi;Ebihara, Mitsuru;Shibata, Seiichi
    • Nuclear Engineering and Technology
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    • 제48권2호
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    • pp.293-298
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    • 2016
  • Thirty-eight spherules from the Antarctic ice sheet were analyzed using neutron activation analysis under two different conditions to investigate their origin. In almost all of these spherules, the contents of iron, cobalt, and manganese were determined to be 31% to 88%, 17 mg/kg to 810 mg/kg, and 0.017% to 7%, respectively. A detectable iridium content of 0.84 mg/kg was found in only one spherule, which was judged to be extraterrestrial in origin. A comparison of elemental compositions of the Antarctic spherules analyzed in this study with those of deep-sea sediment spherules and those of terrestrial materials revealed that most of the Antarctic spherules except for the sample in which iridium was detected could not be identified as extraterrestrial in origin.

Characterization of Korean Clays and Pottery by Neutron Activation Analysis (I). Characterization of Korean Porcelainsherds

  • Lee, Chul;Kwun, Oh-Cheun;Kang, Hyung-Tae
    • Bulletin of the Korean Chemical Society
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    • 제7권1호
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    • pp.73-77
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    • 1986
  • Data on the concentration of Na, K, Sc, Cr, Fe, Co, Cu, Ga, Rb, Cs, Ba, La, Ce, Sm, Eu, Tb, Lu, Hf, Ta, and Th obtained by neutron activation analysis have been used to characterize Korean porcelainsherds by multivariate analysis. The mathematical approach employed is principal component analysis (PCA). PCA was found to be helpful for dimensionality reduction and for obtaining information regarding (a) the number of independent causal variables required to account for the variability in the overall data set, (b) the extent to which a given variable contributes to a component and (c) the number of causal variables required to explain the total variability of each measured variable.

A Study on the Present Levels of Mercury and other Trace Elements in Fresh-water Fish by Neutron Activation Analysis

  • Kim, Nak-Bae;Lee, Chul;Bak, Hae-Ill
    • Nuclear Engineering and Technology
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    • 제8권1호
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    • pp.41-47
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    • 1976
  • Ge(Li) 검출기를 사용한 비파괴 방사화분석법을 이용하여 담수어중 수은 및 기타 미량원소들의 현재 함량 준위를 조사하다. 분석결과에 의하면 지역에 따라 수은의 함량이 크게 변하였으며 이 변화는 아마 지역적인 오염원에 의한 것으로 생각된다. 그리고 분석결과로 부터 미량원소들 중 어떤 원소들 사이에는 뚜렷한 상관관계가 있음을 알았다. 수은 오염의 중요한 원인으로 무연탄 연소가 고려될 수 있을 것으로 생각되어 수종의 무연탄을 분석하였다.

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Characterization of Korean Porcelainsherds by Neutron Activation Analysis

  • Lee, Chul;Kang, Hyung-Tae;Kim, Seung-Won
    • Bulletin of the Korean Chemical Society
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    • 제9권4호
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    • pp.223-231
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    • 1988
  • Some pattern recognition methods have been used to characterize Korean ancient porcelainsherds using their elemental composition as analyzed by instrumental neutron activation analysis. A combination of analytical data by means of statistical linear discriminant analysis(SLDA) has resulted in removal of redundant variables, optimal linear combination of meaningful variables and formulation of classification rules. The plot in the first-to-second discriminant scores has shown that the three distinct territorial regions exist among porcelainsherds of Kyungki, Chunbuk-Chungnam, and Chunnam, with respective efficiencies of 20/30, 22/27 and 14/15. Similar regions have been found to exist among punchong porcelain and ceradonsherds of Kyungki, Chungnam and Chunbuk, with respective efficiencies of 7/9, 15/16 and 6/6. Classification has been further attempted by statistical isolinear multiple component analysis(SIMCA), using the sample set selected appropriately through SLDA as training set. For this purpose, all analytical data have been used. An agreement has generally been found between two methods, i.e., SLDA and SIMCA.