• Title, Summary, Keyword: Synthesis

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New Processing of LED Phosphors

  • Toda, Kenji
    • Transactions on Electrical and Electronic Materials
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    • v.13 no.5
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    • pp.225-228
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    • 2012
  • In order to synthesize LED phosphor materials, we have applied three novel synthesis techniques, "melt synthesis", "fluidized bed synthesis" and "vapor-solid hybrid synthesis", in contrast with the conventional solid state reaction technique. These synthesis techniques are also a general and powerful tool for rapid screening and improvements of new phosphor materials.

A Total Synthesis of Aliskiren Starting from D-Tartrate Diester

  • Kim, Ji Hei;Ko, Soo Y.
    • Bulletin of the Korean Chemical Society
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    • v.34 no.12
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    • pp.3777-3781
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    • 2013
  • A formal total synthesis of aliskiren was accomplished. A key in our synthesis was to use the symmetric ciscisoid-cis-bis-lactone 3' as a precursor, which was prepared from D-tartrate diester. Appending the end groups and functional group transformations completed the synthesis.

Speech synthesis system using Korean prosodic rules (한국어 운율규칙을 이용한 음성합성시스템)

  • 이기영
    • Proceedings of the Acoustical Society of Korea Conference
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    • pp.356-359
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    • 1998
  • This paper proposes the speech synthesis method using Korean prosodic rules as an important technique for Korean speech synthesis. The prosodic model for speech synthesis is composed of accentual phrases and intonational phrases which are derived from hierarchical structure of prosody. This prosodic model controls duration time, intonation and pause of synthesized speech. Synthesis units constitute of demi-syllables and VCV-triphones which can make unlimited vocabularies, and TD-PSOLA is used a sthe synthesis method.

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Approximate Synthesis of 5-SS Multi Link Suspension System (근사 합성법을 이용한 5-SS 멀티 링크 현가장치의 기구학적 설계)

  • 김선평;심재경;안병의;이언구
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.24 no.11
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    • pp.2665-2671
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    • 2000
  • Dimensional Synthesis, which is apart of kinematic synthesis, is to determine the dimensions of a mechanism of preconceived typer for a specified task and prescribed performance. In this paper, in an effort to provide designers with flexibility, a dimensional approximate synthesis method is presented for utilizing prescribed tolerance both the displacement and joint positions of a mechanism to be synthesized. For this, a constrained optimization problem is formulated with displacement parameters and joint positions as variables. The proposed method is applied to the synthesis of a 5-SS multi link suspension mechanism. The method discussed here, however, can be easily applied to any mechanism of which the kinematic constraint equations can be derived.

Synthesis and Biological Evaluation of New Aminothiazolyl Cephalosporins with Elongated Side Chains

  • Kang, Han-Young;Koh, Hun-Yeong;Kim, Mi-Young;Kim, Hyun-Mi;Yoon, Du-Weon;Chang, Moon-Ho
    • Bulletin of the Korean Chemical Society
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    • v.12 no.6
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    • pp.666-673
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    • 1991
  • The elongation of the chain length at 2'position of aminothiazolylacetamido group of cephalosporin antibiotics was achieved. The derivatives with elongated side chain at 2'position were successfully synthesis and their in vitro activities were evaluated. It is indicated that there is an optimum range of the chain length in order to exhibit higher biological activities. This result could open a possibility for the development of the cephalosporin antibiotics with higher activities by further variation of the substituents at other positions. The cephalosporin derivatives with a simple (relatively non-functionalized) side chain as well as with a linear extended side chain were also prepared. Low activities of these derivatives led to a conclusion that either simple (non-functionalized) change or linear elongation of the side chain does not enhance the antibacterial activities.

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A Study on Component Modular Approach for Type Synthesis Automation of Mechanism (기구 형태설계 자동화를 위한 컴포넌트 모듈 접근법에 관한 연구)

  • 김봉주;윤호업;신중호;권순만;장세원
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • pp.1270-1273
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    • 2004
  • The mechanism design is synthesis of suitable mechanism which can be output motions about input motions. That has generally two steps which are the type synthesis and the dimensional synthesis. And required mechanism analysis step for confirming middle or final result. The type synthesis is definition of mechanism type which required aim and the dimensional synthesis is calculation of dimension about defined type mechanism. The type synthesis of mechanism is included qualitative design field which isn't defined systematic design method. especially, the most difficult step for mechanism design automation. In this paper proposed the component modular design method which is figured mechanism types automate with component modules using component modular approach. And develop CAD(Computer Aided Program) program for application.

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Novel Synthesis of 3-Phenyl-chromen-4-ones Using N-Heterocyclic Carbene as Organocatalyst: An Efficient Domino Catalysis Type Approach

  • Mishra, Priya;Singh, Sarita;Ankit, Preyas;Fatma, Shahin;Singh, Divya;Singh, Jagdamba
    • Bulletin of the Korean Chemical Society
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    • v.34 no.4
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    • pp.1070-1076
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    • 2013
  • Herein is reported a simple and efficient synthesis of isoflavones starting from various substituted phenacyl bromides and salicylaldehydes in presence of NHC. The mechanism involved domino catalysis type approach with consumption and regeneration of catalyst in two catalytic cycles. This method proved to be very lucrative and gives very good yield. The method described here represents an environmentally benign alternative to classical approach.