• Title/Summary/Keyword: Convergent synthesis

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Leaching of Copper from Furnace Dust by Pure and Mixed Culture of Thiobacillus ferrooxidans and Thiobacillus thiooxidans

  • Son, Kee-Hang;Lee, Cheal-Gyu;Cho, Nam-Jun
    • Bulletin of the Korean Chemical Society
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    • v.28 no.10
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    • pp.1777-1780
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    • 2007
  • The synthesis of well-defined dendrons based on aliphatic polyether dendritic cores and glassy polystyrene peripheries is described. The synthetic route involves a combination of living anionic polymerization and a stepwise convergent method consisting of iterative Williamson etherification and hydroboration/oxidation reactions. On the basis of molecular weight, as characterized by gel permeation chromatography (GPC), the first generation dendron (Generation-1) shows a random coil conformation like a linear polystyrene, while higher generations (Generation-2 and 3) reveal globular forms in solution.

Synthesis of Dendrimer Containing Dialkylated-fluorene Unit as a Core Chromophore via Click Chemistry

  • Han, Seung-Choul;Jin, Sung-Ho;Lee, Jae-Wook
    • Bulletin of the Korean Chemical Society
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    • v.33 no.1
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    • pp.137-142
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    • 2012
  • The convergent synthetic strategy for the emissive dendrimers having the chromophore at core via the coppercatalyzed 1,3-dipolar cycloaddition reaction between alkyne and azide was described. 2,7-Diazido-9,9-dioctyl-9H-fluorene, designed to serve as the core in dendrimer, was stitched with the alkyne-functionalized Frechettype and PAMAM dendrons by the click chemistry leading to the formation of the corresponding fluorescent dendrimers in high yields. The preliminary photoluminescence studies indicated that 2,7-diazido-9,9-dioctyl-9H-fluorene showed no fluorescence due to the quenching effect from the electron-rich ${\alpha}$-nitrogen of the azido group but the dendrimers fluoresced due to the elimination of the quenching through the formation of the triazole ring.

A Convergent Synthesis of (Z)-13-Octadecen-1-yl Acetate, the Pheromone Mimic of the Rice Leaf Folder Moth and Its Biological Activity Test

  • Kang Suk-Ku;Moon Byoung-Ho;Lee Jeang-Oon;Goh Hyun-Gwan
    • Bulletin of the Korean Chemical Society
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    • v.6 no.4
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    • pp.228-230
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    • 1985
  • (Z)-13-Octadecen-1-yl acetate, the pheromone mimic of the Rice Leaf Folder Moth, Cnaphalocrosis medinalis, was synthesized from 1,13-tridecanediol in three steps. Monoacetylation of 1,13-tridecanediol followed by PCC oxidation gave 13-acetoxytridecan-1-al. Wittig olefination of the 13-acetoxytridecan-1-al with pentylidenetriphenylphosphonium ylide afforded (Z)-13-octadecen-1-yl acetate, the pheromone mimic of the Rice Leaf Folder.

A Computer Mediated Design Development System for Design Innovation - the Focus on the Creative Thinking System for Idea Development in Product Design (디자인 혁신을 위한 창조적 발상지원 시스템 연구)

  • 우흥룡
    • Archives of design research
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    • v.14 no.3
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    • pp.77-85
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    • 2001
  • This paper focuses on the idea development as a creative thinking process for design innovation. The process of thinking has the thinking structures of abduction and transformation. After we had studied the design thought, we found a structure of a thinking system, and created a creative thinking model with this. Using job analysis, we examined the duster of design jobs, which form the design process, and verified the thinking model. The findings suggest that our idea development has the creative process not only of divergent thinking and convergent one, but also of transformation in design. In same time, the design thinking shows their pattern of transition from abstract concept to concrete object. Between the design jobs, idea development shows higher difficulty than other jobs - marketing, product planning and follow-up. Combining the D-T-C (Divergent-Transformation-Convergent) thinking with abstract-concrete thinking, we designed a DFD(data flow diagram) for an early model of computer mediated thinking system (CMTS). This has implications for design support.

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The Effects of Team Learning Behavior, Individual Creativity, Team Shared Mental Model, Mutual Performance Monitoring on Team Creativity in the College Classroom (팀 학습행동, 개인 창의성, 팀 공유정신모형, 상호 수행 모니터링이 대학 수업에서 팀 창의성에 미치는 영향)

  • Jun, Myongnam
    • Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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    • v.5 no.6
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    • pp.317-325
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    • 2015
  • The aim of this research was to investigate the relationship among team learning behavior, individual creativity, team shared mental model(TSMM), mutual performance monitoring on team creativity and then providing the fundamental data on the education. Also it intended to acknowledge relative predictive power on team creativity of independent variables. The total of 257 college students participated the team learning for 6 weeks in a semester. Pearson's product moment correlation and regression analysis were used for data analysis and testing of significance of verification, The main research results are summarized as follows; team learning behavior, TSMM, mutual performance monitoring had no significant effects on three subfactors of team creativity such as novelty, resolution, elaboration & synthesis. Therefore followed researches are needed about inter and intra processing of team creativity.

A Study of Pt-Mg/Mesoporous Aluminosilicate Catalysts for Synthesis of Jet-fuel from n-Octadecane (n-Octadecane 으로부터 항공유 제조를 위한 Pt-Mg/mesoporous aluminosilicate 촉매 연구)

  • Jung, Euna;Kim, Chul-Ung;Jeon, Jong-Ki
    • Korean Chemical Engineering Research
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    • v.54 no.5
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    • pp.712-718
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    • 2016
  • Platinum catalysts supported on the mesoporous material synthesized from Y zeolite were applied to synthesis of jet-fuel through n-octadecane hydroupgrading. The mesoporous aluminosolicate, $MMZ_{HY}$ was synthesized using Y zeolite as its framework source. The effect of the addition of Mg to $Pt/MMZ_{HY}$ catalyst for n-octadecane hydroupgrading was investigated. Catalyst characterization was performed with X-ray diffraction, $N_2$ adsorption, temperature-programmed reduction in hydrogen flow, temperature-programmed desorption of ammonia, and infrared spectroscopy of adsorbed pyridine. The high yield of jet-fuel over the $PtMg(2.0)/MMZ_{HY}$ can be attributed not only to the higher dispersion of Pt metal and higher reducibility, but also the higher amount of acid sites and higher strength of acid sites. The selectivity to iso-paraffin in the jet-fuel fraction could be reached above 80% over the optimized $PtMg/MMZ_{HY}$ catalyst.

A Study on the Encoding of Literature Therapy in the Third Line of the Poem 'Morning' Written by Cho Ji-Hoon (조지훈의 시 「아침」의 3번째 행에 나타나는 문학치료 부호화 연구)

  • Park, In-kwa
    • The Journal of the Convergence on Culture Technology
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    • v.3 no.4
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    • pp.123-129
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    • 2017
  • The purpose of this study is to utilize emotional movement and developmental process in literary therapy. So, I tried to reveal the process of the emotional channel that works in the human body when we deal with literary works. As a result, the emotions confirmed that the emotional codes in the human body were pulled from each other and gathered to the positions of amino acids when the shears were spoken. However, it was judged emotionally to act as a catalyst for the synthesis of amino acids. Of course, this is a humanistic and convergent argument, not a medical proof. However, if these studies continue, it will contribute to making people think more healthily.

Effects of Rumex axetosella, Sonchus oleraceus and Euphoibia jolkini Extracts on Melanin Synthesis in Melanoma Cells (애기수영, 방가지똥 및 암대극 추출물이 Melanoma Cell에서 멜라닌 합성에 미치는 영향)

  • Kim, Min-Jin;Kim, Seoyeon;Hyun, Kwang Hee;Kim, Duk Soo;Kim, Seung-Young;Hyun, Chang-Gu
    • KSBB Journal
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    • v.32 no.3
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    • pp.187-192
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    • 2017
  • In this study, we investigated the effect of Rumex axetosella, Sonchus oleraceus and Euphoibia jolkini extracts on tyrosinase activity and melanin production as natural products of whitening functional cosmetics. To measure the melanin production, 50, 100, $200{\mu}g/mL$ of Rumex axetosella, Sonchus oleraceus and Euphoibia jolkini extracts were treated on ${\alpha}-MSH$ treated B16F10 melanoma cells, respectively. Melanin contents in ${\alpha}-MSH$ treated B16F10 melanoma cells were decreased by 41.5, 51.11, and 61% in $200{\mu}g/mL$ treatment compared to none treatment, respectively. In addition, the intracellular tyrosinase activity was decreased after treatments with all extracts. Furthermore, $100{\mu}g/mL$ of Euphoibia jolkini extract was decreased 81.5% of melanin production in B16F10 melanoma cells. When the three extracts were compared, Euphoibia jolkini extract was considered to be the most functional material for whitening effect.

An Efficient Synthesis of γ-Aminobutyric Acid-Derived Phospholipase A2 Inhibitors from Acyl Cyanophosphoranes and Amine Derivatives (아실 시아노포스포레인과 아민 유도체로 부터 γ-아미노부틸산에서 유도된 포스포리파제 A2 저해제의 효과적인 합성)

  • Lee, Kie-Seung;Kim, Dae-Keun
    • Journal of the Korean Chemical Society
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    • v.48 no.2
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    • pp.161-170
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    • 2004
  • A series of ${\gamma}$-aminobutyric acid-derived, potent human cytosolic phospholipase A$_2$ inhibitors have been prepared from acyl cyanophosphoranes and amine derivatives in a convergent manner. The ${\alpha}$-keto amide functionalities in the inhibitors have been introduced as electrophilic fragments via direct coupling reactions between the labile ${\alpha},{\beta}$-diketo nitriles and ${\gamma}$-aminobutyric acid t-butyl ester derivatives at -78 $^{\circ}C$ in moderate to good yields.