• Title/Summary/Keyword: Large-scale synthesis

Search Result 152, Processing Time 0.027 seconds

Large scale synthesis of the geometrically controlled carbon coils using $Al_2O_3$ ceramic boat for the supporting substrate (산화알루미늄 세라믹 보트 기판을 이용한 탄소마이크로 코일의 대량 합성)

  • Kim, Sung-Hoon
    • Journal of the Korean Applied Science and Technology
    • /
    • v.30 no.3
    • /
    • pp.423-430
    • /
    • 2013
  • Carbon coils could be synthesized using $C_2H_2/H_2$ as source gases and $SF_6$ as an incorporated additive gas under thermal chemical vapor deposition (CVD) system. Prior to the carbon coils deposition reaction, two kinds of samples having different combination of Ni catalyst and substrate were employed, namely, a commercially-made $Al_2O_3$ ceramic boat with Ni powders and a commercially-made $Al_2O_3$ substrate with Ni layer. By using a commercially-made $Al_2O_3$ ceramic boat, the synthesis of carbon coils could be enhanced as much as 10 times higher than that of $Al_2O_3$ substrate. Furthermore, the dominant formation of the microsized carbon coils could be obtained by using $Al_2O_3$ ceramic boat. The surface roughness of the supporting substrate of $Al_2O_3$ ceramic boat was understood to be associated with the large scale synthesis of carbon coils as well as the dominant formation of the larger-sized, namely the microsized carbon coils.

Highly Convenient and Large Scale Synthesis of 5-chloroindole and its 3-substituted Analogues (5-Chloroindole계 화합물의 Large Scale 합성)

  • Keetha, Laxminarayana;Palle, Sadanandam;Ramanatham, Vinodkumar;Khagga, Mukkanti;Chinnapillai, Rajendiran
    • Journal of the Korean Chemical Society
    • /
    • v.55 no.2
    • /
    • pp.240-242
    • /
    • 2011
  • A large scale and commercially feasible synthesis of 5-chloroindole and its 3-substituted analogues has been described via a halogen - halogen exchange reaction from 5-bromoindole and its derivatives using cuprous chloride and dipolar aprotic solvent N-methyl-2-pyrrolidone in one pot with good yields.

Process Development for Large Scale Synthesis of TRH (TRH의 대량합성 제조법 개발)

  • Kim, Dong-Hyeon;Thapa, Pritam;Karki, Radha;Jahng, Yurng-Dong;Lee, Eung-Seok
    • YAKHAK HOEJI
    • /
    • v.51 no.6
    • /
    • pp.490-494
    • /
    • 2007
  • TRH (thyrotropin-releasing hormone) was chemically synthesized utilizing solution phase peptide chemistry for the process development of large scaled synthesis. All the synthetic steps performed in relatively mild conditions, higher yields, easier preparations, minimum racemizations, and separation and purification by recrystallizations.

Synthesis of 2-Deoxy-2-fluoro-D-arabinofuranose Derivatives (2-Deoxy-2-fluoro-D-arabinofuranose류의 합성 연구)

  • 천문우;김문환;김득준;정원근
    • YAKHAK HOEJI
    • /
    • v.28 no.3
    • /
    • pp.191-195
    • /
    • 1984
  • A ten-step synthesis of 1, 3-di-O-acetyl-5-O-benzoyl-2-deoxy-2-fluoro-D-arabino-furanose, a versatile intermediate in the synthesis of chemotherapeutically important nucleosides, was achieved from D-glucose. This procedure affords good overall yields of products and is suitable for large scale preparations.

  • PDF

An Efficient Method for the Large-Scale Synthesis of Atorvastatin Calcium

  • Lee, Hong-Woo;Kim, Young-Min;Yoo, Choong-Leol;Kang, Sung-Kwon;Ahn, Soon-Kil
    • Biomolecules & Therapeutics
    • /
    • v.16 no.1
    • /
    • pp.28-33
    • /
    • 2008
  • Atorvastatin calcium salt (1) was obtained through the preparation of lactone compound (8) from 2-((4R,6R)-6-(2-(2-(4-fluorophenyl)-5-isopropyl-3-phenyl-4-(phenylcarbamoyl)-1H-pyrrol-1-yl)-ethyl)-2-phenyl-1,3,2-dioxaborinan-4-yl)acetic acid tert-butyl ester (9) by hydrolysis in basic condition. Efficient hydrolysis of boronate compound 9 aimed at the viable synthesis for commercial production and purification of Atorvastatin calcium is reported. Detail studies of evaluation procedure are also reported.

Large-Scale Synthesis of Plate-Type ZnO Crystal with High Photocatalytic Activity (광촉매 활성이 우수한 판상형 ZnO 결정의 대용량 합성)

  • Kim, Da-Jung;Kim, Bo-Mi;Joe, Ara;Shim, Kyu-Dong;Han, Hyo-Won;Noh, Gyung-Hyun;Jang, Eue-Soon
    • Journal of the Korean Chemical Society
    • /
    • v.59 no.2
    • /
    • pp.148-155
    • /
    • 2015
  • ZnO nanoplates were prepared by seed-mediated soft-solution process. Photocatalytic property of ZnO nanoplates was superior to that of conventional ZnO nanoparticles owing to the enhanced (0001) plane with large defect sites. In addition, we found that silica coating method could provide to reduce cytotoxicity of ZnO nanoplates. Finally, we have successfully synthesized for the first time large-scale synthesis of plate-type ZnO as few hundreds gram scale for industrial applications through controlling various reagents of growth solution.

Toward Industrial Applications of Graphene Electrodes

  • Hong, Byeong-Hui
    • Proceedings of the Korean Vacuum Society Conference
    • /
    • 2010.02a
    • /
    • pp.39-39
    • /
    • 2010
  • There have been many efforts to utilize the outstanding properties of graphene for macroscopic applications such as transparent conducting films useful for flexible/stretchable electronics. However, the lack of efficient synthesis, transfer, and doping methods limited the scale and the quality needed for the practical production of graphene films. In this presentation, we introduce ultra-large scale (~30 inch) synthesis and roll-to-roll transfer of graphene films showing excellent electrical and physical properties suitable for practical applications. Considering the outstanding scalability/processibility of roll-to-roll and CVD methods and the extraordinary flexibility/conductivity of graphene films, we expect the commercial production and application electrodes replacing the use of ITO can be realized in near future.

  • PDF

Large-Scale Graphene Production Techniques for Practical Applications

  • Bae, Sukang;Lee, Seoung-Ki;Park, Min
    • Applied Science and Convergence Technology
    • /
    • v.27 no.5
    • /
    • pp.79-85
    • /
    • 2018
  • Many studies have been conducted on large-scale graphene synthesis by chemical vapor deposition. Furthermore, numerous researchers have attempted to develop processes that can continuously fabricate uniform and high-quality graphene. To compete with other types of carbon materials (carbon black, carbon fiber, carbon nanotubes, and so on), various factors, such as price, mass manufacturing capability, and quality, are crucial. Thus, in this study, we examine various large-scale graphene production methods focusing on cost competitiveness and productivity improvements for applications in various fields.

A Study on the Synthesis of Decentralized Stabilizing controller for Large Scale Discrete-time Systems with Delays in Interconnections (시간지연이 상호간섭에 존재하는 대규모 선형 이산시간 시스템의 비집중 안정화 제어장치의 설계에 관한 연구)

  • 서일홍;변증남
    • Journal of the Korean Institute of Telematics and Electronics
    • /
    • v.18 no.6
    • /
    • pp.1-8
    • /
    • 1981
  • A new desio method of decentraliaed stabilizing controller is proposed for large scale discretetime systems with delays in interconnections. Gain parameters of the local stabilizing controller are determined by utilizing the well-knowon Nyquist array technique in the complex q-plane, where .

  • PDF