• 제목/요약/키워드: Practical synthesis

검색결과 279건 처리시간 0.035초

Practical Synthesis of $\alpha$-Galactosyl Ceramide, KRN 7000.

  • Song, So-Young;Jung, Song-Kyu;Kim, Sang-Hee
    • 대한약학회:학술대회논문집
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    • 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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    • pp.175.1-175.1
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    • 2003
  • Galactosyl ceramides paly important roles in biological system as immunomodulator and essential constituents of membranes and cell walls. An efficient synthesis of $\alpha$-galactosyl ceramide, KRN 7000, derived from marine sponge Agelas mauritianus as accomplished via a short reaction involving the coupling ceramide moiety and trichloroacetimidate as glycosylation donor. We could synthesize $\alpha$-galactosyl ceramide stereoselectivity without $\beta$-anomer formation on a multigram scale.

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Diasteroselective synthesis of long chained keto amino acids derivatives

  • Kim, Eun-Young;Kim, Eun-Jung;Ko, Hyo-Jin
    • 대한약학회:학술대회논문집
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    • 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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    • pp.347.2-347.2
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    • 2002
  • The unusal keto amino acid. (s)-2-amino-8-oxodecanoic acid(Aoda) is a biologically important constituent of the naturally occurring cyclic tetrapeptides such as apicidins. Consequently extensive chemical modifications of Aoda residue of apicidin were studied, and we are obtained the practical and versatile synthesis of the long-chained keto amino acids in enantlomerically pure form by alkylation with bromoketone and chiral Scholkopf auxiilary. (omitted)

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An Efficient Engineering Design Education Framework in Information Network Engineering

  • Lee, Sang-Gon;Koh, Kyeong-Uk
    • 공학교육연구
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    • 제15권5호
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    • pp.64-68
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    • 2012
  • Design factors such as design objects establishment, analysis, synthesis, production, test and evaluation should be educated in a systematic way. Also design ability to reflect practical restrictive conditions such as industrial standards, economic feasibility, environmental impact, aesthetics, safety and reliability, ethical impacts and social impacts should be cultivated. In this paper, we explain the meaning of these terms and propose a systematic engineering design education framework satisfying Korean engineering education accreditation criteria. We also present a simple implementation in information network engineering.

초음파 분무 열분해법을 이용한 고체전해질용 Lithium Lanthanum Titanium Oxide 제조 (The Synthesis of Lithium Lanthanum Titanium Oxide for Solid Electrolyte via Ultrasonic Spray Pyrolysis)

  • 노재석;양민호;이근재
    • 한국분말재료학회지
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    • 제29권6호
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    • pp.485-491
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    • 2022
  • Lithium lanthanum titanium oxide (LLTO) is a promising ceramic electrolyte because of its high ionic conductivity at room temperature, low electrical conductivity, and outstanding physical properties. Several routes for the synthesis of bulk LLTO are known, in particular, solid-state synthesis and sol-gel method. However, the extremely low ionic conductivity of LLTO at grain boundaries is one of the major problems for practical applications. To diminish the grain boundary effect, the structure of LLTO is tuned to nanoscale morphology with structures of different dimensionalities (0D spheres, and 1D tubes and wires); this strategy has great potential to enhance the ion conduction by intensifying Li diffusion and minimizing the grain boundary resistance. Therefore, in this work, 0D spherical LLTO is synthesized using ultrasonic spray pyrolysis (USP). The USP method primarily yields spherical particles from the droplets generated by ultrasonic waves passed through several heating zones. LLTO is synthesized using USP, and the effects of each precursor and their mechanisms as well as synthesis parameters are analyzed and discussed to optimize the synthesis. The phase structure of the obtained materials is analyzed using X-ray diffraction, and their morphology and particle size are analyzed using field-emission scanning electron microscopy.

유클리드의 자료론(The Data)과 분할론(On Divisons)에 기초한 수학교육에서 분석과 종합에 대한 고찰 (A Study on the A nalysis and Synthesis in Mathematics Education Based on Euclid's 'The Data' and 'On Divisions')

  • 서보억
    • 한국수학교육학회지시리즈C:초등수학교육
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    • 제14권1호
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    • pp.27-41
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    • 2011
  • 본 연구는 분석과 종합에 대한 역사적 출발이라고 볼 수 있는 유클리드의 저작인 '자료론'과 '분할론'에 대한 분석 연구이다. Euclid의 원론에 비해 거의 관심이 없는 두 문헌에 대한 분석을 통해 사고활동으로서의 분석 및 종합에 대한 의미를 살펴보았다. 먼저 분석, 종합이 포함된 다양한 용어들에 대한 개념을 살펴보고, 이를 바탕으로 본 연구에서 사용한 분석과 종합의 개념을 명확화하였다. 또한 두 문헌에 제시된 명제에 대한 분석을 통해 분석은 '외재적 분석'과 '내재적 분석'으로 분류하였는데, 외재적 분석은 제시된 명제에 자체에서 외형적으로 드러난 수학적 대상, 요소, 성질, 속성에 대한 분석이고, 내재적 분석은 외재적 분석의 결과로 추출된 수학적 대상, 요소, 성질, 속성에 대한 재분석 혹은 결합 및 관련성의 추출을 통한 분석이다. 종합은 '이론적 종합'과 '경험적 종합'으로 분류하였는데, 이론적 종합은 경험보다는 논리적, 이성적 과정을 통한 새로운 대상의 추출이고, 경험적 종합은 과거의 학습 경험과 이에 대한 활용을 통한 대상의 추출이다. 이러한 분류를 기초로 하여 초등학교 교과서에 제시된 문제를 통해 실제 적용하여 탐색하였다.

$H_2/O_2$확산화염에서 전기수력학적 방법과 증발기에 의해 발생된 입자의 성장 비교에 관한 실험적 연구 (Experimental study on the Formation and Growth of Silica Particles in $H_2/O_2$ Diffusion Flame by Electro-Spraying Method and Evaporation)

  • 손성혁;육세진;안강호;최만수
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2000년도 추계학술대회논문집B
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    • pp.168-173
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    • 2000
  • Flame aerosol synthesis technology refers to the formation of fine particles from gases in flame and is widely used in practical materials processing. In this paper, an experimental investigation was performed on growth of the silica particles that were generated in $H_2/O_2$ Diffusion Flame by the direct injection or TEOS using Electro-spraying method. in this flame aerosol synthesis, four main parameters or nos interaction (flame temperature, residence time or particle in flame, TEOS flow rate, applied voltage) for particle generation and growth was investigated along the axial direction above the burner. A fairly monodisperse non-aggregated particles were successfully obtained.

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Fast Motion Synthesis of Massive Number of Quadruped Animals

  • Sung, Man-Kyu
    • International Journal of Contents
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    • 제7권3호
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    • pp.19-28
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    • 2011
  • This paper presents a fast and practical motion synthesis algorithm for massive number of quadruped animals. The algorithm constructs so called speed maps that contain a set of same style motions but different speed from a single cyclic motion by using IK(Inverse Kinematics) solver. Then, those speed maps are connected each other to form a motion graph. At run time, given a point trajectory that obtained from user specification or simulators, the algorithm retrieves proper speed motions from the graph, and modifies and stitches them together to create a long seamless motion in real time. Since our algorithm mainly targets on the massive quadruped animal motions, the motion graph create wide variety of different size of characters for each trajectory and automatically adjusted synthesized motions without causing artifact such as foot skating. The performance of algorithm is verified through several experiments

Facile Synthesis of Natural Moracin Compounds using Pd(OAc)2/P(tBu)3-HBF4 as a Sonogashira Coupling Reagent

  • Lee, Jae Jun;Yun, So-Ra;Jun, Jong-Gab
    • Bulletin of the Korean Chemical Society
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    • 제35권12호
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    • pp.3453-3458
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    • 2014
  • An efficient and practical synthesis of natural moracins, which have diverse range of biological properties including anticancer, antioxidant, and antibacterial activities, has been achieved using $Pd(OAc)_2/P(^tBu)_3-HBF_4$ as a Sonogashira coupling reagent which solved the unreactive problems in case of higher electron density of haloaryl compounds in the reaction. Lowering electron density of halophenol with acetylation and changing Sonogashira coupling reagent from $PdCl_2(PPh_3)_2$ to $Pd(OAc)_2/P(^tBu)_3-HBF_4$ smoothly produce the benzofuran structures in the syntheses of moracins M, N and S. The electron deficient halobenzaldehyde, however, easily forms the benzofuran using original Sonogashira conditions, and utilized for the first synthesis of moracin Y.

Recent Progress in Graphene Synthesis and Application

  • Hong, Byung-Hee
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2011년도 제40회 동계학술대회 초록집
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    • pp.3-3
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    • 2011
  • Graphene has been attracting much attention owing to its fascinating physical properties such as quantum electronic transport, a tunable band gap, extremely high mobility, elasticity, thermal conductivity, mechanical strength and so on. There have been many efforts to utilize these outstanding properties of graphene for macroscopic applications such as transparent conducting films useful for flexible/stretchable electronics. However, the scale and the quality graphene need to be further enhanced for practical applications by developing more efficient synthesis, transfer, and doping methods. In this tutorial, the recent advances in graphene synthesis and applications will be reviewed, and discuss the future directions of graphene research.

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Synthesis of Calycotomine via Pictet-Spengler Type Reaction of N,O-Acetal TMS Ethers as N-Acyliminium Ion Equivalents

  • Yang, Jung-Eun;In, Jin-Kyung;Lee, Mi-Sung;Kwak, Jae-Hwan;Lee, Hee-Soon;Lee, Soo-Jae;Kang, Han-Young;Suh, Young-Ger;Jung, Jae-Kyung
    • Bulletin of the Korean Chemical Society
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    • 제28권8호
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    • pp.1401-1404
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    • 2007
  • An efficient Pictet-Spengler type reaction of N,O-acetal TMS ethers for the practical synthesis of 1-substituted tetrahydroquinolines, medicinally important alkaloids, has been accomplished. To demonstrate the versatility of this novel procedure, the total synthesis of calycotomine, a representative 1-hydroxymethyl substituted tetrahydroisoquinoline, is also described.