• 제목/요약/키워드: BH

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BH4 결손증 13례

  • 이동환;홍용희;이용화
    • 대한유전성대사질환학회지
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    • 제9권1호
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    • pp.9-10
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    • 2009
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Examination of the Co-evolution of Galaxies and their Central SMBHs at High Redshifts with Gravitational Lensing by QSO Host Galaxies

  • Taak, Yoon Chan;Im, Myungshin;Kang, Juhyeong;Kim, Jae-Woo;Kim, Dohyeong;Kim, Yongjung
    • 천문학회보
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    • 제40권1호
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    • pp.79.2-79.2
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    • 2015
  • The $M_{BH}-{\sigma}$ relation for galaxies is a stand-out illustration of the co-evolution of galaxies and their central supermassive black holes (SMBHs); however, how this co-evolution occurs and whether this relation holds for SMBHs of the early universe is still a matter of debate. In order to study this at higher redshifts, quasi-stellar objects (QSOs) are the best targets, due to their large sample size and effective $M_{BH}$ estimation. Nevertheless, it is difficult to examine properties of their host galaxies, simply due to the sheer brightness of the QSO itself. Here, we discuss a distinctive method in studying these QSO host galaxies, via gravitational lensing (GL). GL offers a unique approach in determining the mass of the lens object, in this case the host galaxy. QSOs from the SDSS quasar catalog were searched in the Hubble Space Telescope archives, and GL features around them were visually inspected. One such candidate is SDSS J1114-00; to increase its robustness as a GL system candidate, it was observed with the Inamori-Magellan Areal Camera & Spectrograph (IMACS) on the Magellan Baade Telescope at Las Campanas Observatory, to check whether the GL features have identical colors, meaning they are likely to originate from the same source. After confirmation of such GL systems, a sufficiently large sample will enable us to examine the $M_{BH}-{\sigma}$ relation at various redshifts, and in turn, investigate the co-evolution of SMBHs and their host galaxies.

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마이크로 Pin Fin 화학반응기에서 수소화붕소나트륨 수용액의 압력강하 및 탈수소 화학반응 연구 (Pressure Drop and Catalytic Dehydrogenation of NaBH4 Solution Across Pin Fin Structures in a Microchannel Reactor)

  • 정기문;최석현;이희준
    • 대한기계학회논문집B
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    • 제41권6호
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    • pp.381-387
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    • 2017
  • 수소화붕소나트륨은 안정적으로 수소가 저장된 물질이며, 촉매반응으로 수소를 용이하게 분리할 수 있다. 본 연구에서는 탈수소 반응률을 높이기 위해 비표면적이 큰 마이크로 pin fin 화학반응기를 제작하여 수소화붕소나트륨 수용액의 압력강하 및 탈수소 화학반응 실험을 수행하였다. 나노공정을 이용하여 실리콘웨이퍼에 높이 $300{\mu}m$, 직경 $50{\mu}m$의 pin fin을 축간격 1.3, 횡간격 1.5으로 엇갈림 배열하였다. 수소화붕소나트륨 수용액은 5~20 wt.% 농도로 Re수 1~60으로 공급되었으며, 초고속카메라를 이용하여 탈수소반응 유동양상을 관찰하였다. 실험 결과 마이크로 pin fin 화학반응기는 동일 수력학적직경을 가지는 직관 마이크로채널 화학반응기보다 화학반응 성능이 2.45배 우수한 반면, 압력강하는 1.5배 증가하였다.

라텍스 장갑과 마이크로 파이버 속장갑 착용 시 손의 피부수분도 분포 (Distribution of Skin Hydration on the Hand while Wearing Latex Gloves and Inner Gloves)

  • 노상현;현철승;이주영
    • 한국의류학회지
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    • 제41권5호
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    • pp.966-976
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    • 2017
  • This study investigated the effects of wearing latex gloves with inner gloves on the skin hydration of the hands. Fifteen young males participated in the following three conditions: bare hand (BH), latex glove (LG), and latex glove with inner glove condition (LGIG) at an air temperature of $28^{\circ}C$ with 50%RH. Subjects typed a book for 120 min. The results were as follows. Skin hydration was greater for LG and LGIG than BH (p<.001), but no difference was found between LG and LGIG. Skin hydration showed greater values on the thenar and dorsum compared to the palm for both LG and LGIG (p<.05). Skin hydration on the thenar increased during the typing for LG and LGIG, but on the dorsum, palm and finger maintained after 40 min typing. There were positive relationships between hand skin hydration and hand temperature (p<.05). Subjects indicated 'much warmer' and 'more humid' for the LG and LGIG compared to the BH (p<.001), but no differences were found between LG and LGIG. In conclusion, wearing inner gloves inside latex gloves did not induce a reduction of skin hydration and hand temperature; however, significant differences were found in all measurements between bare hands and gloved hands.