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Abstract  

In this work the analysis procedures of fission gas compositions and their isotopic distributions using a gas chromatography (GC) system and/or a quadrupole mass spectrometer (QMS) system were established, and their analysis results were reviewed in order to evaluate their analytical performance. Also, the accumulated data, up to now, regarding fission gas measurement were reviewed to discern any irradiation histories of the punctured fuel rods. A simple gas injection apparatus was designed and fabricated for the quantitative injection of a small volume of fission gas into the GC and the QMS system. With an appropriate temperature controlling of a molecular sieve 5A column, nitrogen, krypton and xenon of a mixture gas was clearly separated within 7 min. According to the analysis results, the relative standard deviation in the determination of fission gas compositions, krypton and xenon, by the GC analysis or by the QMS analysis was about 1%. Based on the review results of the isotopic ratios of krypton and xenon of the released fission gas, it is likely that no abnormally irradiated rods, i.e. defected rods, were included among the punctured rods.

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Abstract  

It is regarded that the spent resins from the water purification systems of moderator (MOD) and the primary coolant of the Canada deuterium uranium-pressurized heavy water reactor (CANDU-PHWR) are a unique waste, owing to their high 14C and gamma-emitting nuclides. In this work, 14C and 3H contents, anion and cation fractions and the predominant gamma-emitting nuclides of the spent resins from 4 units of CANDUPHWRs, were investigated. Also the chemical species of 14C of the spent resins were determined. For a simultaneous separation of 14C and 3H from the spent resins, the wet oxidation-16 wt% H2SO4 stripping process was utilized. The 14C and 3H activity concentration range of the spent resins of the nuclear power plant (NPP), 4 units of all CANDU-PHWR types, was 2.48E5 Bq/g ∼5.33E6 Bq/g, 1.29E5 Bq/g and ∼2.33E5 Bq/g, respectively. Among the analyzed spent resins, the highest 14C and 3H activity concentration was detected in units 4 and 3, respectively. It was found that more than 92% of the 14C activity concentration was retained on the anion resin and the predominant chemical species was inorganic 14C. It was revealed that the anion resin fraction of the spent resins from unit 1 and unit 2, was about 40% and that of unit 3 and unit 4 was around 60%. More than 80% of the total gamma-radioactivity concentration was associated with the cation fraction of the spent resin. The predominant gamma-emitting nuclide of the spent resin for unit 2 was 137Cs, a fission product, and that for unit 4 was 60Co, a corrosion product.

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2003: Uchenye Respubliki Koreia ob otnosheniyah mezhdu gosudarstvami Silla i Bohaj (Ученые Республики Корея об отношениях между государствами Силла и Бохай / Scholars of the Republic of Korea on relations between Silla and Bohai). In: Arheologiia

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. Rosén, S. (1974): A Study on Tones and Tonemarks in Middle Korean. Stockholm, Institute of Oriental Languages, Stockholm University. A Study on Tones and Tonemarks in Middle Korean

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, 435 – 438 . 2. Choi , S. H. , Ryu , K. H. ( 2008 ) Generation of infectious transcripts from Korean strain and mild mottle strain of potato virus X . J. Microbiol. 46

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encephalopathy (BSE)-associated polymorphisms of the prion protein ( PRNP ) gene in Korean native cattle . Anim. Genet. 44 , 356 – 357 . Jeong , B. H. , Kim , N. H. , Choi , E. K. , Lee

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universities in the sample) in computer science, USA holds the first rank, followed by UK, Canada, Denmark, Israel, Germany, etc. China-Taiwan holds the 16th rank, followed by Singapore (19th rank), South Korea (23rd rank), China (24th rank) and India (26th

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Acta Botanica Hungarica
Authors: S. Y. Kondratyuk, L. Lőkös, J. P. Halda, C. Roux, D. K. Upreti, F. Schumm, G. K. Mishra, S. Nayaka, E. Farkas, J. S. Park, B. G. Lee, D. Liu, J.-J. Woo, and J.-S. Hur

. – Nordic Lichen Society , Uddevalla , 116 pp. Aptroot , A. and Moon , K. H. ( 2014 ): 114 new reports of microlichens from Korea, including the description of five new species

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Scientometrics
Authors: Jun-Ying Fu, Xu Zhang, Yun-Hua Zhao, He-Feng Tong, Dar-Zen Chen, and Mu-Hsuan Huang

respectively. South Korea and Japan have similar numbers of publications, ~400 papers. Table 5 Distribution of top ten countries/regions by acupuncture publications over 3 decades

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) Lee , Hong-jik (comp.) ( 2005 ): (Enlarged) Encyclopedia of Korean History . Seoul . [ 李 弘稙 (編) ( 2005 ), (增補)새國史事典 , 서울 .] (The 19th impression of the first edition in 1983

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