• 제목/요약/키워드: Chi-seong

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Taxonomic review of the Korean lumpsucker "Do-chi" reported previously as Eumicrotremus orbis (Pisces: Cyclopteridae) based on morphological and molecular characters

  • Lee, Soo Jeong;Kim, Seong Yong;Moon, Dae Yeon;Kim, Jin-Koo
    • Fisheries and Aquatic Sciences
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    • v.18 no.4
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    • pp.405-410
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    • 2015

  • The Korean lumpsucker, "Do-chi", reported previously as Eumicrotremus orbis, was reinvestigated on the basis of specimens collected from Korea, Japan, and the USA. Morphological and genetic analyses showed that "Do-chi" corresponds to Eumicrotremus taranetzi and clearly differs from E. orbis. Eumicrotremus taranetzi is readily distinguishable from E. orbis by its large, high spiny tubercles with weak, small or no prickles (small, low spiny tubercles with distinct prickles in E. orbis) and 3-4 pairs of spiny tubercles in the dorsal rows (five pairs in E. orbis). We compared partial sequences (466 bp) of the mitochondrial cytochrome c oxidase subunit I genes of "Do-chi" and other Eumicrotremus species. "Do-chi" and E. taranetzi were clustered by the smallest Kimura two-parameter genetic distance (d = 0.000-0.002) and were clearly separated from E. orbis (d = 0.035-0.037). Therefore, our results suggest that the scientific name of the Korean lumpsucker, "Do-chi" should be changed to E. taranetzi.

  • https://doi.org/10.5657/FAS.2015.0405 인용 PDF KSCI

Effect of W Substitution on the Precipitation Behavior of χ and σ Phase in Super Duplex Stainless Steels (슈퍼 2상 스테인리스강에서 χ와 σ상의 석출거동에 미치는 W치환의 영향)

  • Han, Huyn-Sung;Kim, Seong-Hwi;Kang, Chang-Yong
    • Korean Journal of Materials Research
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    • v.26 no.4
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    • pp.200-206
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    • 2016

  • This study was carried out to investigate the effect of W substitution on the precipitation behavior of ${\chi}$ and ${\sigma}$ phases in super duplex stainless steel. The ${\chi}$ phase was precipitated at the interface of ferrite / austenite phases and inside the ferrite phase at the initial stage of aging. With an increase in the aging time, the volume fraction of the ${\chi}$ phase increased, and then decreased with the transformation from the ${\chi}$ phase to the ${\sigma}$ phase. The ${\sigma}$ phase was precipitated later than the ${\chi}$ phase, and the volume fraction of x phase increased with the increase in the aging time. The ferrite phase was decomposed into the new austenite (${\gamma}2$) and ${\sigma}$ phases by aging treatment. The decomposition of the ferrite phase into the ${\gamma}2$ and ${\sigma}$ phases was retarded by W substitution for Mo. The volume fraction of the ${\chi}$ phase increased and that of the ${\sigma}$ phase decreased due to W substitution. The ${\chi}$ and ${\sigma}$ phases were intermetallic compounds, which had lower nickel concentration, and higher chromium, molybdenum, and tungsten concentrations. The ${\chi}$ phase has higher molybdenum and tungsten concentrations than those of the ${\sigma}$ phase. The amounts of chromium and nickel in the ${\chi}$ and ${\sigma}$ phases did not change, but these phases have higher concentrations of molybdenum and tungsten due to W substitution for Mo.

  • https://doi.org/10.3740/MRSK.2016.26.4.200 인용 PDF KSCI