• 제목/요약/키워드: Cascade reaction

검색결과 45건 처리시간 0.027초

Synthesis of Dienamides via the Reaction of Nitrile with Allylindium Reagents and Intramolecular Acyl Group Quenching Cascade

  • Kim, Sung-Hwan;Kim, Yu-Mi;Kim, Jae-Nyoung
    • Bulletin of the Korean Chemical Society
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    • 제31권8호
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    • pp.2351-2356
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    • 2010
  • Various dienamide derivatives were synthesized in reasonable yields from benzonitriles having an amide moiety at the ortho-position, via the sequential (i) In-mediated allylation of nitrile moiety to form an imine intermediate, (ii) intramolecular quenching of an acyl group by the imine intermediate, and (iii) a proton transfer to dienamide.

한국생물공학회 정기총회 및 연구논문발표회 발표논문 (Production of enantiopure epoxides by yeast epoxide hydrolase using a two-phase membrane bioreactor)

  • 최원재;최차용
    • 한국생물공학회:학술대회논문집
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    • 한국생물공학회 2000년도 춘계학술발표대회
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    • pp.145-148
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    • 2000
  • Large-scale resolution of epoxides by the yeast Rhodotorula glutinis was demonstrated in an aqueous/organic two-phase cascade membrane bioreactor. Due to the chemical instability and low solubility of epoxides in aqueous phases, an organic solvent was introduced into the reaction mixture in order to enhance resolution of epoxide. A cascade hollow-fiber membrane bioreactor was used (i) to minimize the toxicity of organic solvents towards the epoxide hydrolase of Rhodotorula glutinis, and (ii) to remove inhibitory amounts of formed diol from the yeast cell containing aqueous phase. Dodecane was selected as a suitable solvent and 1,2-epoxyhexane as a model substrate. By use of this membrane bioreactor, highly concentrated (0.9 M in dodecane) enantiopure (>98% ee) (S)-1,2-epoxyhexane (6.5 g, 30% yield) was obtained from its racemic mixture.

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오디오 정보를 이용한 골프 동영상 자동 색인 알고리즘 (Automatic Indexing Algorithm of Golf Video Using Audio Information)

  • 김형국
    • 한국음향학회지
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    • 제28권5호
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    • pp.441-446
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    • 2009
  • 본 논문에서는 오디오 정보 분석을 이용하여 골프 통영상을 자동 색인하는 알고리즘을 제안한다. 제안하는 알고리즘에서는 입력되는 골프 동영상을 비디오 신호와 오디오 신호로 분리한 후에, 연속적인 오디오 스트림을 Adaboost Cascade 분류방식을 통하여 스튜디오 환경에서의 아나운서의 음성구간, 선수이름이 TV 화면에 소개 될 때 수반되는 음악구간, 선수들의 플레이에 따라 반응하는 관중들의 박수 및 환호성 소리구간, 필드에서의 레포터의 음성구간, 바다나 바람 등의 필드환경 잡음 사운드구간 등의 5가지 구간으로 분류한다. 그리고 드라이브 샷, 아이런 샷과 퍼팅 샷 시에 발생하는 스윙 사운드는 onset 검출과 변조스펙트럼 검증 방법을 통해 검출되며, 관객의 박수 소리 구간과 결합하여 액션 및 하이라이트를 효율적으로 색인할 수 있게 한다. 제안된 알고리즘은 오디오 신호의 간단한 연산을 통해 의미를 지니고 있는 기본구조들을 검출하기 때문에 골프 동영상에서 사용자가 원하는 부분을 빠르게 브라우징하는 임베이디드 시스템에 적용가능하다.

연속식 공중합 반응기의 모델링 및 제어기 설계 (Modeling and controller design for a continuous copolymerization reactor)

  • 황우현;이현구
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1996년도 한국자동제어학술회의논문집(국내학술편); 포항공과대학교, 포항; 24-26 Oct. 1996
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    • pp.788-791
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    • 1996
  • A mathematical model is developed for thermal solution copolymerization of styrene and acrylonitrile in a continuous stirred tank reactor(CSTR). Computational studies are carried out with the continuous copolymerization system model developed in this work to give the monomer conversion, copolymer composition and the average molecular weights of the copolymer. By performing the dynamic analysis of the reaction system, the polymer properties against the changes in the operating conditions are determined quantitatively. The cascade PID and fuzzy controller show satisfactory performances for both set point tracking and disturbance rejection. Especially, the fuzzy controller is superior to the PID controller.

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Importance of Sperm Capacitation, Removal of Cumulus Matrix, Acrosome Reaction, and Sperm-egg Fusion in the Process of In Vitro Fertilization

  • Kim, Ki-Sun;Hwang, Kyung-A;Kim, Hyoung-Chin;Nam, Ki-Hoan;Choi, Kyung-Chul
    • 한국수정란이식학회지
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    • 제26권4호
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    • pp.287-296
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    • 2011
  • Mammalian fertilization is a complex cascade process consisting of sperm migration through the female reproductive tract, physiological changes to sperm such as sperm capacitation and acrosome reaction, and sperm-egg interaction in the oviduct in vivo. On the other hand, in vitro fertilization (IVF) is a process by which egg cells are fertilized by sperm outside the body: in vitro. IVF has been used for a variety of purposes in reproductive biotechnology for human and animals. The discovery of sperm capacitation in 1951 promoted the development of IVF technology. In the initial stage of IVF, sperm capacitation in preincubation medium was shown to be essential to fuse with eggs. Besides, sperms should detour some of the in vivo regulations for IVF. This review introduces a general mammalian fertilization process, including sperm capacitation, removal of cumulus matrix, acrosome reaction, and sperm-egg fusion and focuses on the roles of key biochemical molecules, signal mechanisms, and genes involved during IVF and novel results of sperm-oocyte interaction elucidated in various gene-knockout mice models.